# Panzergranate 44 - German APFSDS



## schwarzpanzer (Apr 3, 2010)

Just wondering what anyone thought on the usefulness of this round?

Leaving aside whether or not it actually did see service, or was used in combat.

My theory is that it wasn't that useful. The KwK 42 and 43 it was developed for were more than enough to deal with any opposing AFV at silly distances, with plain old APCBC/HE (a JS-2 @ 4,600m, apparently), so would be wasteful.

However, it would allow them to deal with the IS-3, albeit at very close range. By which time the IS-3 would probably have knocked them out. Having said that, perhaps plain old AP would have been enough to knock the IS-3 out by spalling? - which Soviet armour was prone to.

As a guide,in the Six-day War, the 90mms of the M48A2 Pattons had considerable difficulty penetrating the IS-3s frontal armour.

In the 128mm, I'm not so sure.

It was not developed for the 75mm KwK40 though - but I believe this is where it would be most useful: allowing for much increased battle effectiveness. Using plain steel shot too - no need for tungsten/wolfram IMO.

It could even have allowed the 50mm L60 to soldier on a bit longer? but creating it for an obsolete gun does seem wasteful - but the gun had weight advantages and was used on the Puma.

Also, in the PaK 36, it might make a useful Fallschirmjager weapon?...

Any thoughts?


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## tomo pauk (Apr 3, 2010)

If that type of ammo required tungsten (think it did), it would've never gotten in production...

For 128mm, why bother with AP(FS)DS? Plan vanilla HE projectile is way cheaper more versatile. Plus even the hit in a mud guard means mission kill for targeted tank, since track would know.


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## hartmann (Apr 3, 2010)

> Also, in the PaK 36,



In fact, It was made an APFSDS shot for the 37 mm PaK36, but I don´t know If it took this designation (PzGr 44). It was known as PPS (Peenemünder Pfeil Geschoss). But this shot was only experimental.




> If that type of ammo required tungsten (think it did



Not necesary. The first 115 mm APFSDS-T for the Soviet gun were of maraging steel, so It was the experimental PPS shot for the PaK 36 (from hardened steel, not from maraging steel).

But, as Germany was in fact manufacturing some very little quantities of PzGr40 in 1944 from Uranium for the PaK39, I don´t see problems to made this shot from Uranium.

This late part is only especulative by the way.
Best regards


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## schwarzpanzer (Apr 3, 2010)

Hi tomo,

Thats a good point on the 128mm. I wonder if HE would be enough to stop an IS tank though? The 128mm had a sloow reload and weighed 10 tons - perhaps it was a pointless weapon, what with the 155mm being available? (I suspect there a new Thread in there somewhere...).

The Conqueror and M103 got a 120mm to deal with the IS-3 though, and modern MBTs use a 128mm L55 too - so it may have had merit?

Personally though, I suspect tat it may have been pintless - and that the 88mm L100 would have been a better prospect.


Hi hartmann,



> In fact, It was made an APFSDS shot for the 37 mm PaK36, but I don´t know If it took this designation (PzGr 44). It was known as PPS (Peenemünder Pfeil Geschoss). But this shot was only experimental.



Great stuff, thanks!  It wasn't that squeeze-bore thing was it? Do you have any more details on it please?



> Not necesary. The first 115 mm APFSDS-T for the Soviet gun were of maraging steel, so It was the experimental PPS shot for the PaK 36 (from hardened steel, not from maraging steel).



Yes, quite true. Also, some PzGr40 APCR used steel cores. I think steel would have been OK for use in KwK40 and under for long-range usage, but not for the KwK 42 and upwards for close-range fights against heavy tanks.



> But, as Germany was in fact manufacturing some very little quantities of PzGr40 in 1944 from Uranium for the PaK39, I don´t see problems to made this shot from Uranium.
> 
> This late part is only especulative by the way.
> Best regards



Ah yes, I'd forgotten about that, thanks for reminding me! Apparently, this was the basis for the rounds in the GAU in the A-10 Warthog (which apparently used APCR, not APDS weirdly enough - is that right?).

This would have been a suitable material for the bigger guns IMO.


Another thing is that, IIRC, some (or all?) PzGr40 had a ballistic cap - so if the PzGr44 also had this feature, it wouldn't have suffered as much from the problems that the British SVDS on the Firefly had.


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## tomo pauk (Apr 4, 2010)

schwarzpanzer said:


> Hi tomo,
> 
> Thats a good point on the 128mm. I wonder if HE would be enough to stop an IS tank though? The 128mm had a sloow reload and weighed 10 tons - perhaps it was a pointless weapon, what with the 155mm being available? (I suspect there a new Thread in there somewhere...).






> The Conqueror and M103 got a 120mm to deal with the IS-3 though, and modern MBTs use a 128mm L55 too - so it may have had merit?



Guns for Conqueror M-103 have had 5-15 years to mess with right kind of ammo, and Brits prefered HESH IIRC.
There is no much sense to compare modern tank armament with one from WW2; BTW its 120-125mm, not 128mm  



> Personally though, I suspect tat it may have been pintless - and that the 88mm L100 would have been a better prospect.



The L100 would be needing tungsten even more to put it's muzzle velocity in a good use - why not 105L80?


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## schwarzpanzer (Apr 4, 2010)

Hi tomo,

I think the Conqueror and M103s were rush-jobs? Basically just throwing a 120mm AA gun onto a Cheiftain/Patton chasis as best they could (which caused allsorts of problems). As for ammo I don't know - bt IIRC the Conquerors was hated, as it was split-loading (like the 128mm), dunno about the M103s - but I expect the same. I can check on that if you like?

What you say about HESH backs up your idea though - using non-penetration methods to defeat armour (as the Soviets did). Perhaps this was the best ( only) way to deal with the IS-3? (Before the 105mm L7, or similar).



> There is no much sense to compare modern tank armament with one from WW2;



There are some parralels that can be drawn though. I have no other things to compare it to. I don't know what the velocity difference was (but that's easily found out) and if the 128mm was to use Uranium APFSDS, then that would form the basis of a good comparison? (Not a _great _one mind, but it's the best I've got to work with).



> BTW its 120-125mm, not 128mm



Oh no! Its not one of those, is it? Like the Comets 77mm and Shermans 76mm guns actually being 76.2mm, you mean? Anyway, you'll have to forgive me if I just call it a 128mm? 



> The L100 would be needing tungsten even more to put it's muzzle velocity in a good use - why not 105L80?



Would tungsten be needed for longer ranges? - and would Uranium be adequate? - That creates 2 more types of round though, which might make loading a knightmare (as was the case with the Sherman 76mm, and the T-54/55).

Your idea of a 105mm is similar to the 105mm L7, which proved succesful, though that was only with APDS? (btw L7 is the designation, not the length in calibres, tee-hee!).


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## hartmann (Apr 4, 2010)

Hello to alll ¡



> Hi hartmann,
> 
> 
> Quote:
> ...



No, It was a true APFSDS shot.
You can see it in the diagram:










> Not necessary. The first 115 mm APFSDS-T for the Soviet gun were of maraging steel, so It was the experimental PPS shot for the PaK 36 (from hardened steel, not from maraging steel).
> Yes, quite true. Also, some PzGr40 APCR used steel cores.




Completely true, Schwarzpanzer. The various types of PzGr40 were filled with Tungsten Carbide, with hardened steel, with SOFT IRON ¡¡¡ and also with uranium cores (ultra-limited quantities).



> which apparently used APCR, not APDS weirdly enough - is that right?).



Completely correct my friend. The GAU gun uses 30mm APCR uranium cored shells. It doesn’t use APDS shots.




> Another thing is that, IIRC, some (or all?) PzGr40 had a ballistic cap



From all the German manuals and info available which I own, all the PzGr 40 shots had a ballistic cap.




> so if the PzGr44 also had this feature, it wouldn't have suffered as much from the problems that the British SVDS on the Firefly had.



 I don’t understand well the question.
An APFSDS-T shot obtains the inherent in-flight stability because of the fins which has, so it doesn’t need from any kind of ballistic cap (although some very late APDS and some early APFSDS-T had a piercing cap to help in highly oblique impacts).




> Quote:
> Personally though, I suspect tat it may have been pointless - and that the 88mm L100 would have been a better prospect.
> The L100 would be needing tungsten even more to put its muzzle velocity in a good use - why not 105L80?



The next gun to upgrade the Tiger IB (aka Königstiger) was a 105mm L60 developed and tested in late 1944 by Krupp.
BTW, As you have said, lengthen the gun to 100 calibres was completely useless, unless will be used a new kind of steel alloy (as maraging steel), tungsten carbide, uranium or something similar. With hardened steel conventional shells, the Germans saw that simply increase the MV was useless if the shell impacted at the objective at more than 1250 m/s (as they proved with the PzGr 39/43 fired at a MV of 1500 m/s versus a 320 mm plate (the shells ever broke upon impact on the plate without obtain complete penetration).





> Perhaps this was the best ( only) way to deal with the IS-3?




The IS3 was still vulnerable to the KwK43 except (theoretically) in the glacis plate. In the practical life, the curious glacis weld in the centre, was a very weak point (even the weld seam broke up several times when the engine tank run at maximum rpm because of harmonic vibration which led to catastrophic failure of the weld seam), so I suspect that a high velocity APCBC 88 mm impact near or on the weld seam would have produced a failure of the weld seam.

BTW, I suspect that the brand new design ultra-blunted nose PzGr 43 APCBC-HE designed for both, the 128 mm and 170 mm would have beaten even at the IS7 (at least, the 170 mm shell)

Best regards. I hope this helps


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## Shortround6 (Apr 4, 2010)

hartmann said:


> Hello to alll ¡
> No, It was a true APFSDS shot.
> You can see it in the diagram:



Was this intended to be service ammunition or was it ammunition made to test a concept?

As in small scale experiment in support of a large size long range gun?

Considering that the projectile is just over 10% lighter than I wouldn't expect any large increase in MV. 

While the weight/energy per sq cm of target area would certainly go up I am not certain if this would elevate the 37mm AT gun to a viable weapon in 1944.

Post war tanks that used APFSDS rounds did so in order to get even higher velocities than they could get with APDS in addition to the higher energy per sq cm of target area.


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## davebender (Apr 4, 2010)

> It could even have allowed the 50mm L60 to soldier on a bit longer? but creating it for an obsolete gun does seem wasteful


I think the opposite is true. By 1942 Germany has thousands of 5cm/42 and 5cm/60 weapons in service. By providing them with APFSDS rounds they remain effect vs most enemy armor for the remainder of the war. The catch is that you need enough tungsten to mass produce the new sabot rounds, which Germany didn't have.

If enough tungsten were available...
I would issue some APFSDS rounds to the 3.7cm Flak43 units. This superb AA gun (250 RPM) entered service in 1944. With sabot rounds I suspect it would be dangerous to medium tanks like the T-34 and Sherman.


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## tomo pauk (Apr 5, 2010)

schwarzpanzer said:


> Hi tomo,
> I think the Conqueror and M103s were rush-jobs? Basically just throwing a 120mm AA gun onto a Cheiftain/Patton chasis as best they could (which caused allsorts of problems). As for ammo I don't know - bt IIRC the Conquerors was hated, as it was split-loading (like the 128mm), dunno about the M103s - but I expect the same. I can check on that if you like?



Yep, I've read that Conqueror had problems with loading the main ammo.



> What you say about HESH backs up your idea though - using non-penetration methods to defeat armour (as the Soviets did). Perhaps this was the best ( only) way to deal with the IS-3? (Before the 105mm L7, or similar).



If you go for kill with any kind of AP ammo, you need to hit the tank just the right place (to ignite ammo/fuel, engine, or to kill crew member(s)). And non-uranium penetrators do not ignite easy.
If you hit with heavy enough HE/HESH, your not-so-good hits would've make enemy tank destroyed.





> There are some parralels that can be drawn though. I have no other things to compare it to. I don't know what the velocity difference was (but that's easily found out) and if the 128mm was to use Uranium APFSDS, then that would form the basis of a good comparison? (Not a _great _one mind, but it's the best I've got to work with).



As for comparing the cannons, the comparison with russian 122 130mm, and US 120mm of WW2 does make sense. But comparison with smooth-bore modern cannons is not that valid IMO.



> Oh no! Its not one of those, is it? Like the Comets 77mm and Shermans 76mm guns actually being 76.2mm, you mean? Anyway, you'll have to forgive me if I just call it a 128mm?



Okay, I'll call them 5in then 



> Would tungsten be needed for longer ranges? - and would Uranium be adequate? - That creates 2 more types of round though, which might make loading a knightmare (as was the case with the Sherman 76mm, and the T-54/55).



If you're developing new cannon, you better make the best ammo for it, or your tank end up like Russian T-62s T-72s - burning wrecks after Merkavas M1s got them. 
The issue for Germans at the end of WW2 was lack of tungsten, that's why I 'propose' 105mm, firing HE/HEAT, and just a fraction of AP ammo.



> Your idea of a 105mm is similar to the 105mm L7, which proved succesful, though that was only with APDS? (btw L7 is the designation, not the length in calibres, tee-hee!).


I know about L7; trivia for you: how the Brits call their 120mm tank gun. Starts with an 'L' too...
As for ammo, it also sports HESH HE.


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## davebender (Apr 5, 2010)

> issue for Germans at the end of WW2 was lack of tungsten, that's why I 'propose' 105mm, firing HE/HEAT, and just a fraction of AP ammo.


I agree. However I don't think a 10.5cm HEAT round is necessary to destroy WWII era armor. 

Armour penetration table
Early model German 7.5cm HEAT rounds will penetrate 100mm of armor. The more advanced 8.8cm Panzerschreck HEAT warhead would penetrate 209mm of armor. That's plenty powerful. You could build a relatively light weight (i.e. moderate velocity) 8.8cm anti tank cannon that fires modern HEAT rounds. As a bonus the same rounds are also effective against soft targets like machinegun emplacements.


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## tomo pauk (Apr 5, 2010)

When you add the shell that envelopes 8,8 cm HEAT projectile from Panzerschrek, necessary to reinforce it so it could withstand the stress of being fired from long gun, the 'new' projectile ends ticker than 10 cm - perhaps 10,5cm 

The moderate velocity gun would've been nice, but then you cut on the efficient range the ability to easily hit a moving target.


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## davebender (Apr 5, 2010)

> moderate velocity gun would've been nice, but then you cut on the efficient range the ability to easily hit a moving target


The 75mm M3 cannon on the Sherman tank had a velocity of 2,031 ft/sec (619 m/s). Everythng I've read suggests it could hit enemy tanks at normal WWII combat ranges. It just didn't penetrate armor very well. A hypothetical 8.8cm or 10.5cm tank cannon with a similiar muzzle velocity should work as long as they have HEAT shells.


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## tomo pauk (Apr 5, 2010)

At what combat ranges 75mm was able to hit a tank sized, moving target?

On a more affirmative note, perhaps Germans might have went British Russian way - necking up the cannon ammo (7,5cm to 8,8 for German gun)? Guess the muzzle weight would've been above 600 m/s for the 50% increase in shell weight? Good enough when dealing with Russians W. Allies, for no reduction of ammo count on Pz-IV?


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## Shortround6 (Apr 5, 2010)

You can estimate the point blank range of a tank or anti-tank gun by taking the MV and adding 10%.
as in MV 619M/s + 61.9meters for 681 meters. 

ALL projectiles will fall 16ft in their first second of flight. Aiming the gun up slightly from dead level means the shell (if sights are pointed at the middle of a 10ft tall tank) will rise slightly until at about 350-400meters it is hitting the top of the turret and at 650-675 meters the shell would hit the bottom edge of the hull (or there abouts). In WWII when range was obtained using the MK I eyeball mistakes in range were very common. 

as the range lengthens things get a lot worse real quick. In the second second of flight the projectile will fall 48 ft more. Assuming the gross simplification of no air resistance so the shell keeps a constant speed our Sherman gunner will have to point the barrel at a point in space 64 ft (19.4 meters) above the target at a range of 1240 meters. guessing the range wrong by even 100 meters may mean a miss. Using a gun with a MV of 930M/S means a flight time of 1.5 seconds and much less drop and a flatter angle as the shell comes down for a larger danger area. 

HEAT shells evolved a tremendous amount during WW II and after. Cone shape, cone material and fusing all played parts. The higher the spin rate on the shell the worse it worked in practice. A reason for post war smooth bore guns and/or slipping driving bands. It was also found that a certain stand of distance was needed for the jet to form properly. High velocity impacts crushed the nose of the shell and shortened the stand of distance (reason for some of those long nose probes on post war shells).

Penetration of armor is no guarantee of a kill. Penetration by a high velocity projectile means a lot of metal (the stuff that used to be where the hole is) flying around the tank at high speed. Many heat shells are rated by the thickness that the jet will just penetrate, in order to do significant damage to what is behind the armor either the exact right spot must be hit or the shell must have a good margin of over penetration. This is one reason the British went with HESH shells, They thought that the existing HEAT shells didn't do enough damage behind the armor.


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## schwarzpanzer (Apr 7, 2010)

This post is so long, I had to do it in 2 parts! Sorry if this anoys anyone - if it does, just let me know OK? Thanks.

*Hi hartmann,*

That is truly EXCELLENT info, thankyou!



> Completely correct my friend. The GAU gun uses 30mm APCR uranium cored shells. It doesn’t use APDS shots.



I wonder why not?? IIRC it had testing problems with sabot parts causing jams - perhaps that was it?



> From all the German manuals and info available which I own, all the PzGr 40 shots had a ballistic cap.



Ah right, thankyou. That APFSDS doesnt seem to have a BC though, wonder if the PzGr44 did?...



> I don’t understand well the question.
> An APFSDS-T shot obtains the inherent in-flight stability because of the fins which has, so it doesn’t need from any kind of ballistic cap (although some very late APDS and some early APFSDS-T had a piercing cap to help in highly oblique impacts).




Sorry, yes I was referring to the 'bouncing' - which was a problem for SVDS. Also, a spinning penetrator is more likely to be deflected IIRC? Another advantage would be increased resistance to shatter. One more thing, SVDS had poor after-penetration damage, Uranium penetrators would not this problem ( be better than APHE?).



> The next gun to upgrade the Tiger IB (aka Königstiger) was a 105mm L60 developed and tested in late 1944 by Krupp.



Great stuff, thanks! Sounds sensible.



> BTW, As you have said, lengthen the gun to 100 calibres was completely useless, unless will be used a new kind of steel alloy (as maraging steel), tungsten carbide, uranium or something similar.



I wonder if the 88mm L100 would perform OK with a Uranium penetrator? - Or with standard PzGr39/43 at longer distances? Removing the HE filler would have been a wise move IMO. Still, such a long barrel would make a vehicle hard to maneuver! I wonder if the 88mm L100 suffered from the same negative effects as the 75mm L100 did? (barrel whip etc).



> With hardened steel conventional shells, the Germans saw that simply increase the MV was useless if the shell impacted at the objective at more than 1250 m/s (as they proved with the PzGr 39/43 fired at a MV of 1500 m/s versus a 320 mm plate (the shells ever broke upon impact on the plate without obtain complete penetration).



I think the most the Germans had to worry about was 280mm (max on the IS-3), though I suppose the slope of the armour will have increased that.



> The IS3 was still vulnerable to the KwK43 except (theoretically) in the glacis plate.



Even on the turret? (280mm, sloped very well). It did have a slight shot-trap though.



> In the practical life, the curious glacis weld in the centre, was a very weak point (even the weld seam broke up several times when the engine tank run at maximum rpm because of harmonic vibration which led to catastrophic failure of the weld seam), so I suspect that a high velocity APCBC 88 mm impact near or on the weld seam would have produced a failure of the weld seam.



Excellent info. Like the Char SOMUA in a way then.



> BTW, I suspect that the brand new design ultra-blunted nose PzGr 43 APCBC-HE designed for both, the 128 mm and 170 mm would have beaten even at the IS7 (at least, the 170 mm shell)



What were the penetration figures for thse new shells, do you know? Were they the same type as used in the KwK 43? I thought the 128mm L55 used PzGr43 only? as standard?



> Best regards. I hope this helps



You too mate, thankyou! - it is truly astonishing info. Is it OK if I ask where you got that drawing from?


*Hi Shortround,*



> As in small scale experiment in support of a large size long range gun?



I suspect it was just intended to eek out more performance from the 'Army doorknocker' - when Germany still had tungsten coming out of her ears. This round may have been able to take out a Matilda II easily? Funny that they rejected this, and stayed with APCR - though this design seems to use a lot of tugsten.



> Considering that the projectile is just over 10% lighter than I wouldn't expect any large increase in MV.



But the drag would be much decreased - meaning much higher terminal velocity. Also carrying weight.



> While the weight/energy per sq cm of target area would certainly go up I am not certain if this would elevate the 37mm AT gun to a viable weapon in 1944.



I think this was scrapped well before that, it just illustrates the plans that led to the PzGr44 in the 75mm up. As to it's usefullness in 1944 - well, we shall see on this thread... What vehicles still used a 37mm in 1944 anyway?



> Post war tanks that used APFSDS rounds did so in order to get even higher velocities than they could get with APDS in addition to the higher energy per sq cm of target area.



They used sliding collars, or smoothbore guns? - If so, they are pretty different. These fins amy have acted like a Tallboys? (though not seemingly so, form those drawings). I don't have info on cold war rifled AP(FS?)DS to hand right now, sorry. Which guns were you meaning?

More info will be needed on these PPS rounds (fins? sliding collars?), great info again hartmann!

Some nice info at the bottom there Shortround - explained it much better than I could. One thing though:

This is one reason the British went with HESH shells, They thought that the existing HEAT shells didn't do enough damage behind the armor.

As I mentioned above, spalling doesn’t cause fires (?), whereas HEAT does all too readily – so why would they think that? Still, it could allow the vehicle to be recovered?..


*Hi davebender,*



> I think the opposite is true. By 1942 Germany has thousands of 5cm/42 and 5cm/60 weapons in service. By providing them with APFSDS rounds they remain effect vs most enemy armor for the remainder of the war. The catch is that you need enough tungsten to mass produce the new sabot rounds, which Germany didn't have.



Thats an interesting viewpoint. Normal steel would have done the job, as it did in some APCR rounds, which hartmann has mentioned above. Also, Uranium was used too. Soft Iron might be a bit 'unsuitable' though!



> If enough tungsten were available...
> I would issue some APFSDS rounds to the 3.7cm Flak43 units. This superb AA gun (250 RPM) entered service in 1944. With sabot rounds I suspect it would be dangerous to medium tanks like the T-34 and Sherman.



Could be, maybe even the odd IS-2? It would make them better able to defend themselves agaist roaming tanks - but was this necessary?
This is seemingly very similar to the thinking behind the GAU 30mm in many ways?



> I agree. However I don't think a 10.5cm HEAT round is necessary to destroy WWII era armor.
> 
> Armour penetration table
> Early model German 7.5cm HEAT rounds will penetrate 100mm of armor. The more advanced 8.8cm Panzerschreck HEAT warhead would penetrate 209mm of armor. That's plenty powerful. You could build a relatively light weight (i.e. moderate velocity) 8.8cm anti tank cannon that fires modern HEAT rounds. As a bonus the same rounds are also effective against soft targets like machinegun emplacements.



Thanks for the link. HEAT are seemingly less effective than KE penetrators for a given penetration figure, so you want as much peformance as possible. I think you're idea is a sound one - but increasing the calibre will greatly increase the performance, but not weight or recoil. I'm not so surre on HEAT being good against infantry - not till dual-purpose HEAT rounds came on the scene (long after WW2?).



> The 75mm M3 cannon on the Sherman tank had a velocity of 2,031 ft/sec (619 m/s). Everythng I've read suggests it could hit enemy tanks at normal WWII combat ranges. It just didn't penetrate armor very well. A hypothetical 8.8cm or 10.5cm tank cannon with a similiar muzzle velocity should work as long as they have HEAT shells.



True, good point. A crack-shot could even get a Stug III E 75mm L24 to work!


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## schwarzpanzer (Apr 7, 2010)

Hi tomo,

You get a post all to yourself!



> If you go for kill with any kind of AP ammo, you need to hit the tank just the right place (to ignite ammo/fuel, engine, or to kill crew member(s)). And non-uranium penetrators do not ignite easy.



The round bounces around like a pool ball, so it does often it something (unless the crew's REALLY lucky). Also, in forcing it's way through the armour, it becomes incandecent (but doesnt explode like APHE or Uranium). Tungsten penetrators are the worst performes here - despite giving the best penetration qualities.



> If you hit with heavy enough HE/HESH, your not-so-good hits would've make enemy tank destroyed.



I don't think spalling can ignite a tank (?). But it can injure or destroy the workings /or crew.



> As for comparing the cannons, the comparison with russian 122 130mm, and US 120mm of WW2 does make sense. But comparison with smooth-bore modern cannons is not that valid IMO.



Why not? It just seems to me that the 128mm was closer in concept to a modern AT gun, than the Russian 122/130mm? - If it used Uranium APFSD, I was just trying to figure it out as best I could sorry. Funnily enough, old-style AP shells apparently work well against modern armour!



> Okay, I'll call them 5in then



NOOOOO!!



> If you're developing new cannon, you better make the best ammo for it, or your tank end up like Russian T-62s T-72s - burning wrecks after Merkavas M1s got them.



Too right. You know some of thse Iraqi tanks fired cheap Chinese steel penetrators? 



> The issue for Germans at the end of WW2 was lack of tungsten, that's why I 'propose' 105mm, firing HE/HEAT, and just a fraction of AP ammo.



HEAT - great idea! Why didn't I think of that? What is wrog with me lately?? Anyway, yes, great idea. Tungsten may not have been a problem - steel or Uranium could be used, depending on the situation. This causes problems though - different ammos for different situations, but the same ammo in different guns for different situations.  A similar problem was in the T-54 T-55 - it used HEAT for long-range, AP for close-range, which was much more confusing than simply using a single round (APDS) in Western tanks for all anti-tank situations.

Going on from your HEAT point, perhaps tht would be the best ammo type for the 128mm? - or would make the 150mm seem more sensible again?



> I know about L7; trivia for you: how the Brits call their 120mm tank gun. Starts with an 'L' too...
> As for ammo, it also sports HESH HE.



L30? Also APFSDS too - all these ammo types! HESH is losing out now though - due to spall liners.



> When you add the shell that envelopes 8,8 cm HEAT projectile from Panzerschrek, necessary to reinforce it so it could withstand the stress of being fired from long gun, the 'new' projectile ends ticker than 10 cm - perhaps 10,5cm



Sorry, I don't understand.



> The moderate velocity gun would've been nice, but then you cut on the efficient range the ability to easily hit a moving target


. 

Thats true, as these guns get bigger and shorter, ability to hit ever faster targets diminishes. 

Even then though, even a miss with a large HE shell might disable the target vehicle - allowing a lethal 2nd shot...



> At what combat ranges 75mm was able to hit a tank sized, moving target?



1,000 yards+, if memory serves(?). I will check.

Edit: Here we go:



PlanD said:


> The Sherman M4s cannon, M3 75mm, could destroy the F/2 at around 1000 metres. I know for a fact that the Shermans optical sights were able to provide the vision required for armoured battles at those ranges. Normal combat range being 400 - 600 metres, the Sherman was in a good solid position against the IV F/2. As the F/2 was not in full position to destroy the Sherman until at 1000 metres, the same distance for the Sherman.
> 
> Both tanks optics gave them good sighting at 1000m.



So 1,000 metres then. It depends how fast the target is moving, and size. If it was a battle tank, it would be likely to be stopped and shooting? A light tank would be a harder taget (small, fast not engaging). The M3 was the interim gun though - there was an earlier M2 75mm - with lower MV, and a later 76mm M1A1 - with higher MV.

If you're trying to hit a target far away, then max gun elevation plays a big part.


----------



## Shortround6 (Apr 7, 2010)

schwarzpanzer said:


> They used sliding collars, or smoothbore guns? - If so, they are pretty different. These fins amy have acted like a Tallboys? (though not seemingly so, form those drawings). I don't have info on cold war rifled AP(FS?)DS to hand right now, sorry. Which guns were you meaning?



Things like the Russian 115mm on the T-62. Went to smooth bore in order to fire APFSDS at quel or higher velocities than the Western 105 fired APDS. When the west goes to APFSDS they have to figure a way to fire the projectile out of an existing rifled gun while imparting the least amount of rotation possible. 

French 90mm smooth bore guns fired fin stabilized HEAT rounds. American 90mm tank guns which were rifled also fired a fin stabilized round but needed driving bands that would slip/slide on the shell body to reduce the amount of spin. French later went to the extent of having an outer shell body that rotated separated from the inner body that held the shaped charge by ball or roller bearings. as can be imagined, while these projectiles were effective they also took time to perfect. 






schwarzpanzer said:


> This is one reason the British went with HESH shells, They thought that the existing HEAT shells didn't do enough damage behind the armor.
> 
> As I mentioned above, spalling doesn’t cause fires (?), whereas HEAT does all too readily – so why would they think that? Still, it could allow the vehicle to be recovered?..



Again it depends on the amount of over penetration. If a heat round that will "JUST" penetrate 180mm of armor hits a plate 170mm thick you may only get a hole a few millimeters in diameter (smaller than your finger) and the jet of flame and molten material may not be all that big. 

If the Hesh round hits (and hesh can be over matched, thick enough armor will stand up to a small HESH warhead) it was supposed to (and often did) cause a spall larger than a dinner plate weigh a number of pounds to flying around the tank at hundreds of miles an hour. The tank may not burn but the inside of the tank is going to look pretty beat up. Crew is going to look a little less than parade ground also.

Of course a number of countries disagreed with the British so maybe they are wrong. 
Just don't think that a WW II Heat shell that penetrates 105mm of armor is guaranteed to destroy a tank with 100mm armor.


----------



## tomo pauk (Apr 7, 2010)

schwarzpanzer said:


> Hi tomo,
> 
> You get a post all to yourself!



You're da man 



> The round bounces around like a pool ball, so it does often it something (unless the crew's REALLY lucky). Also, in forcing it's way through the armour, it becomes incandecent (but doesnt explode like APHE or Uranium). Tungsten penetrators are the worst performes here - despite giving the best penetration qualities.



There is difference between a single piece of metal weighting 0,5-1 kg (due to penetrating AP shot) and plenty of such pieces of same weight - the later would do untold damage to crew, fuel, ammo...



> I don't think spalling can ignite a tank (?). But it can injure or destroy the workings /or crew.



Yep - crew would've suffered collectively.



> Why not? It just seems to me that the 128mm was closer in concept to a modern AT gun, than the Russian 122/130mm? - If it used Uranium APFSD, I was just trying to figure it out as best I could sorry. Funnily enough, old-style AP shells apparently work well against modern armour!



Why would you consider the 128mm more modern (= better?) than Russian pieces? 
"Modern AT gun" is oxymoron though



> NOOOOO!!






> Too right. You know some of thse Iraqi tanks fired cheap Chinese steel penetrators?



Either cheap or expensive, you don't want steel penetrators for your MBTs anyway.



> HEAT - great idea! Why didn't I think of that? What is wrog with me lately?? Anyway, yes, great idea. Tungsten may not have been a problem - steel or Uranium could be used, depending on the situation. This causes problems though - different ammos for different situations, but the same ammo in different guns for different situations.  A similar problem was in the T-54 T-55 - it used HEAT for long-range, AP for close-range, which was much more confusing than simply using a single round (APDS) in Western tanks for all anti-tank situations.



Question is whether Russkies knew about APDS, or have had working APDS?


> Going on from your HEAT point, perhaps tht would be the best ammo type for the 128mm? - or would make the 150mm seem more sensible again?



If you're outnumbered, you want healthy ammo count. Though having different versions of heavy AFV - one with 105-128, other with 150mm would've been feasible, even on Panther's chassis.



> L30? Also APFSDS too - all these ammo types! HESH is losing out now though - due to spall liners.



Indeed, L30 
Guess more companies are developing APFSDS than HESH now.



> Sorry, I don't understand.



Simple math: Panzerschreck shell is 8,8cm in diameter. It's enveloped by thin tin, perhaps 1 mm tick (included in those 8,8cm). If we want to use the same 8,8cm shell in our tank gun, it would be fired at much greater acceleration from there. So we'd reinforce it by enveloping it into a much ticker shell, say, 8mm tick (16mm all together for both sides). So we have 8,8cm + 1,6cm = 10,4cm. That's just 1mm under our 105mm gun. 
. 


> Thats true, as these guns get bigger and shorter, ability to hit ever faster targets diminishes.
> 
> Even then though, even a miss with a large HE shell might disable the target vehicle - allowing a lethal 2nd shot...



Agree with that.



> 1,000 yards+, if memory serves(?). I will check.
> 
> Edit: Here we go:
> 
> ...



Perhaps Pz-IV would've been more useful if it fired projectiles 50% heavier, while retaining both ammo count, and AT abilities? Of course, US 3in necked-up to, say, 90mm, or Russian 85mm necked-up to 100mm...


> If you're trying to hit a target far away, then max gun elevation plays a big part.



Indeed, but I'd rate sights crew experience even more


----------



## schwarzpanzer (Apr 7, 2010)

*Hi Shortround,*

Ah yes, when I said 'collars', I meant 'driving bands'. .

Thanks for the info though. I knew about the AFSDS on the 120mm L30, but not previous Cold War stuff.

Ah yes, I know about HEAT rounds - but a lot of people dont (thanks to Hollywood?). I posted a link a while ago on tests done by the Americans with a Bazooka on a captured Panther - want me to post it?

It's like the Bazooka theoretically could penetrate 100mm - but in practise wasn't much use against a Tigers hull front.



> (and hesh can be over matched, thick enough armor will stand up to a small HESH warhead)



Very interesting. I don't suppose you have the rough rules for that? Soething to do with plate thickness vs calibre diameter I'll guess?

The problem with HESH is that the tank can be recovered (which can be a good thing though, depending on who owns the battlefield after the action is over) - also spall liners can render it useless - just a thin layer of Kevlar, or similar. I think maybe ductile armour (like that on the Sherman) may also be immune from it?


*Hi tomo,*



> You're da man



Damn right!



> There is difference between a single piece of metal weighting 0,5-1 kg (due to penetrating AP shot) and plenty of such pieces of same weight - the later would do untold damage to crew, fuel, ammo...



True, but I'd much rather have an ignition, if possible (unless I was low on tanks myself, or they were all obsolete). Still, if the only things that will penetrate are tungsten rods or HESH - then there's no choice, right? So HESH would be the best option beteen those 2 choices then?



> Why would you consider the 128mm more modern (= better?) than Russian pieces?



Because it was designed mainly as an anti-tank gun (?) - not a gun-howitzer (?).



> "Modern AT gun" is oxymoron though



Why is that? The Rheinmetal on the Abrams is one? (supposedly dual-purpose, but it's HE abilities were apparently neglected - leaving the 105mm on the M60 to do that).



>



You like being cruel to me, don't you? 



> Either cheap or expensive, you don't want steel penetrators for your MBTs anyway.



True on modern MBTs (but not so much in WW2, @ long distances), but apparently old fashioned AP is good for breaking up modern composite armour - so it's coming full-circle?



> Question is whether Russkies knew about APDS, or have had working APDS?



They had similar, but couldn't get it to work in the D-10T 100mm - hence the adoption of the less-than desireable 115mm in the T-62, and the variety of ammo types in the D-10T. There was an attempt to make a 100mm firing this round though. It did stellar work in the 76mm gun on the PT-76 apparently though in Vietnam.



> If you're outnumbered, you want healthy ammo count. Though having different versions of heavy AFV - one with 105-128, other with 150mm would've been feasible, even on Panther's chassis.



True, but I think the Germans went too far - does a tank _really _need to hold around 90 rounds?

The Panther chassis was too flawed IMO, but one of a similar weight maybe?

I was just wondering if it would be better to do away with the 128mm and just make 150mm's?

The 105mm always had advantages though - and was also used as a deperation heavy ATG early in the war when the 37mm couldn't cope, like the 88mm Flak was (though at shorter ranges).



> Indeed, L30
> Guess more companies are developing APFSDS than HESH now.



Sorry, I have a confession to make: I looked it up.
I have explained some of the the disadvantages of HESH at the end of my reply to Shortround, directly above.



> Simple math:



Translation:

English: Simple math = Schwarzpanzerese: Incredibly complicated Mathematical equation - RUN!!

Thanks for explaining though - even I understood that!



> Perhaps Pz-IV would've been more useful if it fired projectiles 50% heavier, while retaining both ammo count, and AT abilities? Of course, US 3in necked-up to, say, 90mm, or Russian 85mm necked-up to 100mm...



What was the difference between the 'Stub' 'Special's projectile weights? Necking up is good, but the PzIV's KwK 40 was necked up anyway (the PaK 39 on the Hetzer wasn't). Necking up might have done the Soviets and Americans some good though - maybe the 3in gun married up to the 105mm M2 breech? (Which happened anyway IIRC? - but wasn't that popular, for some silly reason - forgets the guns designation, sorry).



> Indeed, but I'd rate sights crew experience even more



True, and it also doesn't matter so much on HV guns, but the 75mm M3 was a reasonably low-velocity gun (though that's debatable).


----------



## tomo pauk (Apr 8, 2010)

schwarzpanzer said:


> *Hi tomo,*
> 
> True, but I'd much rather have an ignition, if possible (unless I was low on tanks myself, or they were all obsolete). Still, if the only things that will penetrate are tungsten rods or HESH - then there's no choice, right? So HESH would be the best option beteen those 2 choices then?



With any properly stowaged ammo, you're odds are pretty long if you bet on ignition. Killed crew is always bigger loss for enemy.


> Because it was designed mainly as an anti-tank gun (?) - not a gun-howitzer (?).



A-19 was cannon, not gun-howitzer. 
For that 'it was designed for something, therefore it's better than some all-rounder' you'd have to throw some really good arguments - designing a dedicated AT gun order to be a towed piece is/was pretty faulty decision IMO.


> Why is that? The Rheinmetal on the Abrams is one? (supposedly dual-purpose, but it's HE abilities were apparently neglected - leaving the 105mm on the M60 to do that).



When you say AT gun, it's a towed AT gun in my eyes, not a tank gun 



> True on modern MBTs (but not so much in WW2, @ long distances), but apparently old fashioned AP is good for breaking up modern composite armour - so it's coming full-circle?



Don't mix steel-cored APFSDS with steel full-bore AP 


> They had similar, but couldn't get it to work in the D-10T 100mm - hence the adoption of the less-than desireable 115mm in the T-62, and the variety of ammo types in the D-10T. There was an attempt to make a 100mm firing this round though. It did stellar work in the 76mm gun on the PT-76 apparently though in Vietnam.



That 'less than desireable' point need some explanation IMO.



> True, but I think the Germans went too far - does a tank _really _need to hold around 90 rounds?



25 rounds is pretty low, more so if you have numerical disadvantage.


> The Panther chassis was too flawed IMO, but one of a similar weight maybe?



Panther's chassis was available, but anything similar would've do.



> I was just wondering if it would be better to do away with the 128mm and just make 150mm's?



105 150 combo 



> The 105mm always had advantages though - and was also used as a deperation heavy ATG early in the war when the 37mm couldn't cope, like the 88mm Flak was (though at shorter ranges).



i'd venture to say that a handful of 10,5cm field guns were more likely to fire at tanks than 10,5cm Flak 



> What was the difference between the 'Stub' 'Special's projectile weights? Necking up is good, but the PzIV's KwK 40 was necked up anyway (the PaK 39 on the Hetzer wasn't). Necking up might have done the Soviets and Americans some good though - maybe the 3in gun married up to the 105mm M2 breech? (Which happened anyway IIRC? - but wasn't that popular, for some silly reason - forgets the guns designation, sorry).



Necking-up is connected to frontal part of a cartridge, not the aft part. Brits have necked-up 57mm to 75mm, but size of breech remained the same; Russkies have necked-up 12,7mm to 20mm, and 14,5mm to 23mm (don't confuse that one with VYa-23 ammo). They all have doubled/tripled shell (projectile) weights, at cost of 1/4 of muzzle velocity. 


> True, and it also doesn't matter so much on HV guns, but the 75mm M3 was a reasonably low-velocity gun (though that's debatable).



Nothing was wrong with that gun


----------



## hartmann (Apr 8, 2010)

Hello to all 



> Hi hartmann,
> 
> That is truly EXCELLENT info, thank you!



I am happy being useful. 



> IIRC it had testing problems with sabot parts causing jams - perhaps that was it?



It was probably a very good reason. The sabots tend to jam the gun when it included a muzzle brake. But also may be from the ejection of the sabots from the gatling gun spinning. Truly I don’t know the exact reason/s behind.




> wonder if the PzGr44 did?...



I don’t know, sincerely. All I could collect until now from manuals, other people and so on in German hardware, are rare serial and experimental shells and shots, ranging from APCR, APDS to APFSDS, and HEFSDS, but nothing very solid .



> Sorry, yes I was referring to the 'bouncing' - which was a problem for SVDS



Ok, I understand now (You can also name it as "tumbling" )



> Also, a spinning penetrator is more likely to be deflected IIRC?



Yes, Also, APCR/SVAP shot works in a slightly different way compared to APFSDS (hidrodynamical/fluid way compared to elasto-plastic deformation).



> Another advantage would be increased resistance to shatter



It all depends on the manufacture quality and material used (the APDS manufactured by UK in the WWII were very brittle because inadequate sinterised technology, in contrast to Germany). 




> Uranium penetrators would not this problem ( be better than APHE?).



Well. That is a matter of the uranium family (called Actinides). All have pyrophoric effects when they are finely powdered and oxidized. Concerning If It was better than AP-HE, I don’t know completely well (but in both cases, very nasty effects for the crew and ammo loaded ).



> The next gun to upgrade the Tiger IB (aka Königstiger) was a 105mm L60 developed and tested in late 1944 by Krupp.
> Great stuff, thanks! Sounds sensible.



You can check in Jentz books some data and drawings concerning this proposal.




> I wonder if the 88mm L100 would perform OK with a Uranium penetrator?



Even the 88 L71 with uranium cored PzGr 40/43 would have been better than conventional tungsten carbide core (it is denser), so I don’t imagine the final results with the 88 L100 gun  .



> Or with standard PzGr39/43 at longer distances?



Undoubtedly, It would have performed better at longer distances with a PzGr 39/43, but the barrel erosion would have been extreme If they increasde the propellant charge .




> Still, such a long barrel would make a vehicle hard to maneuver! I wonder if the 88mm L100 suffered from the same negative effects as the 75mm L100 did? (barrel whip etc).



As you say, It would probably behaved all the same problems (and It would have been too difficult to handle )



> Even on the turret? (280mm, sloped very well).



Seen the drawings, I only found a maximum thickness of 220 mm of casted steel in the turret (which would probably equivalent to some 190 mm of good rolled homogeneous armour)










> BTW, I suspect that the brand new design ultra-blunted nose PzGr 43 APCBC-HE designed for both, the 128 mm and 170 mm would have beaten even at the IS7 (at least, the 170 mm shell)
> What were the penetration figures for these new shells, do you know?



I have some scarce data for the 128 mm L66 gun at some 1080 m/s with the PzGr43 versus plates of 80-90 Kg/mm2 strength was punching trough something like 270-276 mm at 30º. With the standard 128 mm L55 gun, it consistently punched through 248 mm at 30º with 950 m/s.
Also I have some data with plates placed at 45º.
Note: All the trials carried by the Germans showed that the PzGr 39 for this gun behaved better at 0 to 30º, but that the PzGr 43 behaved better from 30º to 60º 

Concerning the 17 cm L50 KwK44 gun with PzGr 43 shell, if I read the table correctly, had a MV of some 850 m/s with the PzGr 43 shell weighing 71 Kg and should punch trough 290 mm of hardened steel at 30º at 850 m/s.




> Were they the same type as used in the KwK 43?



Not exactly the same. The head was a modified even blunter design (if It was possible ).



> I thought the 128mm L55 used PzGr43 only?



The 128 mm L55 used two AP rounds. Firstly, in trials it used a round named simply as “PzGr”, or PzGr 39, a conventional APCBC-HE shell. Sometime after, it was designed the “PzGr 43” round.




> as standard?



I don’t know for sure. 

It should have been the standard, although I don’t know If the initial AP round was dropped or If It was manufactured among the PzGr 43. (That is really dark info mate, probably completely lost for ever).




> Is it OK if I ask where you got that drawing from?



There is no problem ,
I obtained It from a friend, and incidentally, it appeared sometime after in a forum. Also I have a photograph of a fired APFSDS shot (although I have no permission to post it unless this person will allow It ).



> Was this intended to be service ammunition or was it ammunition made to test a concept?



I don’t know for sure, but I guess (as the people which owns a shot) that It would have been probably a test concept shot for larger calibres (may be 75, 88 or bigger). Although I don’t discard the possibility of being a “fresh air” for the good old PaK36.




> Considering that the projectile is just over 10% lighter than I wouldn't expect any large increase in MV



Well, that is true, but the sectional density and piercing ability would go up far more than it could be expected from a single 10 % loss of weight as it is far less surface to give the energy carried.

Hope this helps


----------



## schwarzpanzer (Apr 10, 2010)

Hi tomo,



> With any properly stowaged ammo, you're odds are pretty long if you bet on ignition.



I was thinking that crews often fire on a vehicle until it 'brews up'. If the gun relies on spalling, that wont happen(?). Also, if the enemy vehicle catches fire - then that will show it is oviously finished, so you can move onto the next one, and not bother with a following shot. As a counter to this, I think APHE is not a good thing - too far the other way.



> Killed crew is always bigger loss for enemy.



Good point. I was thinking of the Ferdinands 'lost' at Kursk though - which were recrewed. This would still have hurt though. Ferdinands were rarities though, against ordinary vehicles though, yes thats right-on.



> A-19 was cannon, not gun-howitzer.
> For that 'it was designed for something, therefore it's better than some all-rounder' you'd have to throw some really good arguments - designing a dedicated AT gun order to be a towed piece is/was pretty faulty decision IMO.



Isn't 'cannon' a little ambiguous? A quick look on Wikipedia calls it a Field Gun. I'm afraid I don't know the difference between a Field Gun, and a Gun-Howitzer.

I think the 128mm was always intended to be self-propelled, and function mainly as an AT gun. Having learned from experience with the PaK 43. I haven't seen a PaK 44 as a towed gun, I don't think?

My main reasoning is, that as I see it, the A-19 was a 'jack-of-all-trades', with main function being HE - whwereas the 128mm was intended to fight tanks from the outset - giving it the edge (AP ammo, velocity, sighting etc).



> When you say AT gun, it's a towed AT gun in my eyes, not a tank gun



Sorry. When I mention 'AT gun' I often mean anti-tank, tank or anti-tank, towed gun. Tank guns come in many flavours in my language: AT, DP (Dual-Purpose), Support and Howitzer - to name but a few. When I say AT - I could mean the PaK 40, KwK 40 or both. Sorry, I will try to be clearer in future, though I can be sloppy. I take it you are more into towed artillery then? We should be able to fill each others gaps in knowledge very well then.



> Don't mix steel-cored APFSDS with steel full-bore AP



Sorry, I just used that as a tangeant example. My meaning with using steel for APDS not being a problem is: at longer distances, MV will be reduced (but still be better than full-bore AP rounds) - so shatter will not be such a problem, but penetration will be improved. At close ranges though, shatter will be very likely - so APCBC would probably be better instead.



> That 'less than desireable' point need some explanation IMO.



Sorry, it was more to do with the vehicle it ws mounted in being too small for it (the T-62), than the gun itself. I suppose though, that the new smoothbore would have less HE performance than the old D-10T? It was actually eventually replaced with the old D-10T, firing APDS.



> 25 rounds is pretty low, more so if you have numerical disadvantage.



True, I was meaning that the Soviets had too few rounds (28), whereas the Germans had too much (about 90). I believe a compromise would be between the two would be about right. IMO, I think 50-60 rounds?



> Panther's chassis was available, but anything similar would've do.



Later Jagdpanthers were OK - but a bit late in the game perhaps? I think the Panthers chassis was far too fragile, expensive and unreliable to be of much use. I think Germanys failure to produce a decent chassis in the 40-50 ton class is what lost them the war.



> 105 150 combo



You know, I'm actually coming back full-cirle again. - I wonder if the 128mm could replace both 105 150mm calibres? I think though, that for various reasons mentioned before (development, tooling etc) that a mix of 105 150mm would be preferable: 105mm firing APCBC APFSDS for harder targets, with still a decent HE charge, and a 150mm firing HE, HEAT and APCBC. Both proved to be decent weapons in WW2 - with the 128mm being < desireble, but not in the lengths firing the ammo types we're discussing.



> i'd venture to say that a handful of 10,5cm field guns were more likely to fire at tanks than 10,5cm Flak



I was talking about the FH18, sorry. This was used (succesfully) to attack tanks and destroyed a T-34 on at least one occasion. The FH18 could only engage at close range though (unlesss using HEAT - but was that available for it?). Your point is true though - did a 105mm flak gun ever attack a tank in WW2? If you could marry the Flak FH designs though- that should give you a good headstart?



> Necking-up is connected to frontal part of a cartridge, not the aft part. Brits have necked-up 57mm to 75mm, but size of breech remained the same; Russkies have necked-up 12,7mm to 20mm, and 14,5mm to 23mm (don't confuse that one with VYa-23 ammo). They all have doubled/tripled shell (projectile) weights, at cost of 1/4 of muzzle velocity.



Sorry, when you said necked-up, I thought you meant necked-down (bottle-necked, Maroschek). I've never heard of what you are talkig of before - love new info! So, an oversized projectile was put on a stndard cartridge? I've heard about this being done with HEAT warheads on PaK 36s 38s, but never anyting else -thanks!

Necking-up would increase HE/HEAT payload, but ruin MV - as is the case with the QF 75mm you mentioned. Good food for thought again, thanks! (but now my brain hurts!).



> Nothing was wrong with that gun



Some might beg to differ...


----------



## schwarzpanzer (Apr 10, 2010)

Sorry, another 2-parter. I'll have to ask, is there a problem with the length of my posts? I don't want people to get irritated with me.

Hi hartmann,



> I am happy being useful.



You must be happy, like all the time then?



> It was probably a very good reason. The sabots tend to jam the gun when it included a muzzle brake. But also may be from the ejection of the sabots from the gatling gun spinning. Truly I don’t know the exact reason/s behind.



I've got the info in an A-10 book I have - which is buried in 'the pile'. I may ask in the Aviation weapons Forum though...



> I don’t know, sincerely. All I could collect until now from manuals, other people and so on in German hardware, are rare serial and experimental shells and shots, ranging from APCR, APDS to APFSDS, and HEFSDS, but nothing very solid



That's OK. Info on the PzGr44 is notoriously hard to come by - not helped by the fact that I've forgotten everything. The fact that it would have had a BC never even occured to me - untill recently I didn't know that all PzGr40 39s had BCs. You d have excellent info though - I never even heard of that PPS round before.8) I would consider it to be 'prototype PzGr44'? IIRC though, PzGr44 had 2 sets of fins? - never even thought to look for a BC though. Any ifo you still have on the PzGr44 would be much appreciated though.



> Ok, I understand now (You can also name it as "tumbling"



Is that what hapens in deflected shots/shells? - the same thing as causes wounding to tissue in rifle rounds? - never new that! Sounds reasonable though...



> Yes, Also, APCR/SVAP shot works in a slightly different way compared to APFSDS (hidrodynamical/fluid way compared to elasto-plastic deformation).



Never knew that either. Getting lots of good info here! When you say SVAP - do you mean Super Velocity Armour-Piercing - APDS? I think some APFSDS spin? I suppose a spinning projectile can 'drill' it's way through armour though - on the flipside? Otherwise though, it's just wasting it's KE, and scrubbing off speed?



> It all depends on the manufacture quality and material used (the APDS manufactured by UK in the WWII were very brittle because inadequate sinterised technology, in contrast to Germany).



What?! The tungsten?? This almost too much to take in for one day!



> All have pyrophoric effects when they are finely powdered and oxidized.



Would this automatically happen upon penetration? - or is it a manufacturing process?



> You can check in Jentz books some data and drawings concerning this proposal.



Actually, you've jogged my memory. IIRC now, it was intended for the E-75? Which Jentz book please?



> Even the 88 L71 with uranium cored PzGr 40/43 would have been better than conventional tungsten carbide core (it is denser), so I don’t imagine the final results with the 88 L100 gun



I heard tungsten was much denser than steel? - unless I'm getting confused with 'harder'?

As for the 88mm L100 -yeah, that would've been nasty!8)



> Undoubtedly, It would have performed better at longer distances with a PzGr 39/43, but the barrel erosion would have been extreme If they increasde the propellant charge



True, but as with the KT and MG42, it would likely have been a quick-change design. I wonder how the barrel was on the flak version? - how many pieces?...

The performance of the 75mm L100 over the L70 was hardly worthwhile though, with PzGr39/43 - I wondered if this'd be the same? I wonder if an L100 barrel causes roblems irrespectie of calibre? I think though, that it matters less as the calibre rises? - also being dependant on the thickness and quality of the armour plates it is fired at. For example, a 37mm L100 would be pretty pointless! 

I wonder if performance would be improved with the standard propellant charge? Also, on that point, I wonder what length the barrel should be to burn the propellant entirely (which IIRC starts to cause new problems though). 



> As you say, It would probably behaved all the same problems (and It would have been too difficult to handle)



Would an L100 always have those problems then? It wouldn't have been that difficult to handle - the L71 round was heavy, but could still fire at 20+rpm. Better than a larger calibre, anyway? (which alays have slow RoFs). Still, time for an autoloader perhaps? If you mean for a vehicle - well I've seen proposas for it fitted in a tank TD - and the design looks sound (though definately not for urban combat lol).



> Seen the drawings, I only found a maximum thickness of 220 mm of casted steel in the turret (which would probably equivalent to some 190 mm of good rolled homogeneous armour)



Yes, having checked again, it would seem thats the case. I'm sure 280mm for the turret front is a common figure given though?  - so, if that is the case, a 230mm gun then!



> I have some scarce data for the 128 mm L66 gun at some 1080 m/s with the PzGr43 versus plates of 80-90 Kg/mm2 strength was punching trough something like 270-276 mm at 30º. With the standard 128 mm L55 gun, it consistently punched through 248 mm at 30º with 950 m/s.
> Also I have some data with plates placed at 45º.



Great info - that should do it! (assuming the IS-3 never had 280mm). Are those angles from vertical? - so vertical would be 0 degrees, not 90?



> Note: All the trials carried by the Germans showed that the PzGr 39 for this gun behaved better at 0 to 30º, but that the PzGr 43 behaved better from 30º to 60º



That makes sense. I can try to explain why, if you like?



> Concerning the 17 cm L50 KwK44 gun with PzGr 43 shell, if I read the table correctly, had a MV of some 850 m/s with the PzGr 43 shell weighing 71 Kg and should punch trough 290 mm of hardened steel at 30º at 850 m/s.



Even if the IS-3 did have 280mm - it's toast!



> Not exactly the same. The head was a modified even blunter design (if It was possible ).



Ah, that explains a question I had to myself the other day. Yes, it is possible. I forgot the BC design changed from PzGr39 to 39/43. Also, IIRC the BC design on the PzGr40 changed in the 40/43. I'm pretty sure. So theres 3 different BC designs?: PzGr 39, PzGr 39/43 PzGr 39/43 (2nd design) - ?



> The 128 mm L55 used two AP rounds. Firstly, in trials it used a round named simply as “PzGr”, or PzGr 39, a conventional APCBC-HE shell. Sometime after, it was designed the “PzGr 43” round.



It would seem there are 2 PzGr 43 rounds. I think the 1st was called PzGr 39/43, the 2nd just PzGr 43. I can check. As to the earlier type, I just don't know - but it may have just been PzGr 39 from the earlier 128mms?

You can see why the loaders would have a knightmare! - poor sods!

Still, green = HE, black = AP - best leave it at that eh?



> I don’t know for sure.
> 
> It should have been the standard, although I don’t know If the initial AP round was dropped or If It was manufactured among the PzGr 43. (That is really dark info mate, probably completely lost for ever).



I may actually be able to help there (pay you back for the wonderful APFSDS ammo eh?). It may have used some of the older projectiles though - the situation was pretty desperate, so I think they'll have just used what was available. Either way, even the old PzGr 39 was more than enough for anything in the 128mm L55, except maybe the odd, very rare IS-3.



> There is no problem ,
> I obtained It from a friend, and incidentally, it appeared sometime after in a forum. Also I have a photograph of a fired APFSDS shot (although I have no permission to post it unless this person will allow It ).



I was kinda hoping it was a scan from a book. I was wanting to show it to an associate (I wont unless you give me permission). Thanks anyway though. If that photo is a good one, it may show a Ballistic Cap? (or not). If it's the PPS in that drawing though, then it probably wont (?)



> I don’t know for sure, but I guess (as the people which owns a shot) that It would have been probably a test concept shot for larger calibres (may be 75, 88 or bigger). Although I don’t discard the possibility of being a “fresh air” for the good old PaK36.



When was it developed? - That should explain it, one way or the other. I wonder how much use it would be in the Pak 36?



> Well, that is true, but the sectional density and piercing ability would go up far more than it could be expected from a single 10 % loss of weight as it is far less surface to give the energy carried.



Thats true - it's not all about weight -aerodynamics factor in too. As well as what hartmann has said (a reduction in skin friction/parasitic drag), I suspect the Cd would also be greatly reduced (though I would need to see the projectiles to be sure).



> Hope this helps



Awesome info, as always.8) - though now I have a headache!(in a good way though)


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## Shortround6 (Apr 11, 2010)

schwarzpanzer said:


> Good point. I was thinking of the Ferdinands 'lost' at Kursk though - which were recrewed. This would still have hurt though. Ferdinands were rarities though, against ordinary vehicles though, yes thats right-on.



Kind of depends on your goals, IF you win the battle and occupy the ground then the enemy can't re-crew the vehicles because you captured them.
If your ammo choice has less penetration but greater "flammable" effects if does penetrate you may not wind up driving the enemy from the field in the first place.




schwarzpanzer said:


> Isn't 'cannon' a little ambiguous? A quick look on Wikipedia calls it a Field Gun. I'm afraid I don't know the difference between a Field Gun, and a Gun-Howitzer.



In General (and there are more than a few cross overs) Field Guns use fewer different powder charges (to adjust for range) and have higher velocity. Some feild guns (75mm) use fixed ammo with non-adjustable powder charges.


schwarzpanzer said:


> I think the 128mm was always intended to be self-propelled, and function mainly as an AT gun. Having learned from experience with the PaK 43. I haven't seen a PaK 44 as a towed gun, I don't think?
> 
> ...whwereas the 128mm was intended to fight tanks from the outset - giving it the edge (AP ammo, velocity, sighting etc).



128 was intended to be a general purpose gun, replacing the 10cm field gun (not howitzer) which was thought too heavy for the weight of shell it used and more range was wanted too. 


schwarzpanzer said:


> , MV will be reduced (but still be better than full-bore AP rounds) - so shatter will not be such a problem, but penetration will be improved. At close ranges though, shatter will be very likely - so APCBC would probably be better instead.



Shatter was a problem at somewhere between 2000-2600fps depending on projectile (and heat treatment) armor (and heat treatment) and which source you believe. Steel APDSFS might be in trouble at any practical range because the idea behind (or at least one of them) is that the APFSDS projectile slows down the least amount with range. 



schwarzpanzer said:


> I was talking about the FH18, sorry. This was used (succesfully) to attack tanks and destroyed a T-34 on at least one occasion. The FH18 could only engage at close range though (unlesss using HEAT - but was that available for it?). Your point is true though - did a 105mm flak gun ever attack a tank in WW2? If you could marry the Flak FH designs though- that should give you a good headstart?



Trying to marry the two doesn't work. the starting requirements for the two are too far apart. The Flak gun needs fixed ammo (shell crimped into cartridge case) to obtain a high rate of fire. The howitzer needs separate ammunition because it needs to be able to adjust the powder charge from low to high in order to cover the full range of targets, like lobbing a shells over a ridge and into the valley just beyond. A Flak gun would not only shoot over the ridge but the entire valley and maybe the the next ridge 
Howitzer barrels also lasted much longer than flak barrels, mostly because they used much less powder per shot, low charge levels caused almost negligible wear but use of full or super charges had to be carefully noted in log books and sometimes came with restrictions on how many could be fired in a row. 

also see the weight difference between the 10.5 cm leFH 18 and the 10 cm schwere Kanone 18, a little under 2000kg compared to over 5,500kg. for just about the same shell.


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## tomo pauk (Apr 11, 2010)

schwarzpanzer said:


> Hi tomo,
> I was thinking that crews often fire on a vehicle until it 'brews up'. If the gun relies on spalling, that wont happen(?). Also, if the enemy vehicle catches fire - then that will show it is oviously finished, so you can move onto the next one, and not bother with a following shot. As a counter to this, I think APHE is not a good thing - too far the other way.



If you mange a hit with HESH, there is no need to hit it time and again - you know that it represents hardly any threat, so you can move on to the another target.



> Good point. I was thinking of the Ferdinands 'lost' at Kursk though - which were recrewed. This would still have hurt though. Ferdinands were rarities though, against ordinary vehicles though, yes thats right-on.



There is many anecdotes that go this way: Allied tank gets knocked down, crew escapes, returns to the tank park and then returns to the front line with a brand new M4. 



> Isn't 'cannon' a little ambiguous? A quick look on Wikipedia calls it a Field Gun. I'm afraid I don't know the difference between a Field Gun, and a Gun-Howitzer.ops


:

The dividing line was pretty clear cut for field artillery back then: howitzers were able to fire up to 70-80 deg, while cannons could've managed perhaps 45 deg; howitzers did have multi-part propelling charges, while cannons had fixed charge in most cases; howitzers were much more 'price effective', since they were able to throw the heavier weighs then cannons (for same ordnance weight); the price for that is that howitzers have had much smaller muzzle velocity - so, smaller range penetration (for AP ammo); howitzer shell' steep trajectory offers more advantage vs. well entrenched targets. 
Therefore I still consider A-19 as cannon 
The 'gun-howitzers' are suppose to embrace the best from both worlds, and form the bulk of modern field artillery park. Russian ML-20 (152mm) offered almost twice the shell weight compared with A-19 (122mm), while being of same weight. The range reduction was some 20%, and, since it out-ranged the 99% of German field artillery pieces, they continued it producing in numbers.
The shortcoming was that it weighted twice as 152mm howitzer, for same shell weight; range was some 12km vs. 17km for ML-20.
The British 25pdr 5,5in could be also regarded as gun-howizers.



> I think the 128mm was always intended to be self-propelled, and function mainly as an AT gun. Having learned from experience with the PaK 43. I haven't seen a PaK 44 as a towed gun, I don't think?



It was trialed at captured French Russian carriages, so perhaps they were intending to use it as a towed piece? 


> My main reasoning is, that as I see it, the A-19 was a 'jack-of-all-trades', with main function being HE - whwereas the 128mm was intended to fight tanks from the outset - giving it the edge (AP ammo, velocity, sighting etc).



A-19, while indeed a jack-of-all-trades, was pretty good in all of them, but certainly the newer 128mm was offering come advantages in sheer power sights.


> Sorry. When I mention 'AT gun' I often mean anti-tank, tank or anti-tank, towed gun. Tank guns come in many flavours in my language: AT, DP (Dual-Purpose), Support and Howitzer - to name but a few. When I say AT - I could mean the PaK 40, KwK 40 or both. Sorry, I will try to be clearer in future, though I can be sloppy. I take it you are more into towed artillery then? We should be able to fill each others gaps in knowledge very well then.



No probs - the constructive talk about weaponry is at my liking 
I'm in artillery as in any piece of militayry hardware, but arty doesn't catch any limelight (=topics).



> Sorry, I just used that as a tangeant example. My meaning with using steel for APDS not being a problem is: at longer distances, MV will be reduced (but still be better than full-bore AP rounds) - so shatter will not be such a problem, but penetration will be improved. At close ranges though, shatter will be very likely - so APCBC would probably be better instead.



Guess we'd need some really good info about steel AP ammo vs. modern armor 



> Sorry, it was more to do with the vehicle it ws mounted in being too small for it (the T-62), than the gun itself. I suppose though, that the new smoothbore would have less HE performance than the old D-10T? It was actually eventually replaced with the old D-10T, firing APDS.



Yep, too bad T-62 was just 'another T-54/55' IMO, but it's main shortcomings were sights other fancy (but useful) stuff Western tanks have had.


> True, I was meaning that the Soviets had too few rounds (28), whereas the Germans had too much (about 90). I believe a compromise would be between the two would be about right. IMO, I think 50-60 rounds?



I guess you've heard many stories about Typhoons P-47s blasting German tanks. That was exaggeration, but, when they managed to blast their supply trucks (carrying ammo among other stuff), that was almost equal as if they were blasting the tanks themselves.
So, if your (German) tank unit has 90 round per tank, there was nothing wrong with that.


> Later Jagdpanthers were OK - but a bit late in the game perhaps? I think the Panthers chassis was far too fragile, expensive and unreliable to be of much use. I think Germanys failure to produce a decent chassis in the 40-50 ton class is what lost them the war.



Too late 
As for 40-50 ton vehicle, they've just needed to copy KV (but with 8,8 in turret) an be done with that.



> You know, I'm actually coming back full-cirle again. - I wonder if the 128mm could replace both 105 150mm calibres? I think though, that for various reasons mentioned before (development, tooling etc) that a mix of 105 150mm would be preferable: 105mm firing APCBC APFSDS for harder targets, with still a decent HE charge, and a 150mm firing HE, HEAT and APCBC. Both proved to be decent weapons in WW2 - with the 128mm being < desireble, but not in the lengths firing the ammo types we're discussing.



With 105 150 you have ready pieces to take it on Russkies, while 128mm was pretty rare, and not really embraced by Army during WW2. But with orders being of right timing, there is no doubt that 128mm would've be available in numbers to supplant both calibres.



> I was talking about the FH18, sorry. This was used (succesfully) to attack tanks and destroyed a T-34 on at least one occasion. The FH18 could only engage at close range though (unlesss using HEAT - but was that available for it?). Your point is true though - did a 105mm flak gun ever attack a tank in WW2? If you could marry the Flak FH designs though- that should give you a good headstart?



You mean 10,5cm* le*FH18? I guess any hit from that at T-34 would've been quite a nuisance 
I guess mating leFH carriage with Tiger's cannon would've been easy, but that would have been just another towed AT gun. 


> Sorry, when you said necked-up, I thought you meant necked-down (bottle-necked, Maroschek). I've never heard of what you are talkig of before - love new info! So, an oversized projectile was put on a stndard cartridge? I've heard about this being done with HEAT warheads on PaK 36s 38s, but never anyting else -thanks!



The necking-up also includes the wider barrel to accommodate the wider projectile.
The 3,7cm Pak was using the usual barrel standard cartridge (minus the projectile) in order to fire a huge round that was attached to the muzzle - something like rifle grenades used even today. That was NOT necking-up though.



> Necking-up would increase HE/HEAT payload, but ruin MV - as is the case with the QF 75mm you mentioned. Good food for thought again, thanks! (but now my brain hurts!).



The MV that got 'ruined' was still enough to enable white phosphorus shells to be fired from 75mm - guess you wouln't like to be on receiving end of that. 
BTW, 'soft' targets were more likely to be encountered from Normandy on, than Panther al, so 75mm was pretty good choice.


> Some might beg to differ...



With everybody in agreement, we'd have nothing to discuss


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## schwarzpanzer (Apr 12, 2010)

Hi Shortround,



> Kind of depends on your goals, IF you win the battle and occupy the ground then the enemy can't re-crew the vehicles because you captured them.



Agree 100% - and then you can repair them if necessary and use them yourself...



> If your ammo choice has less penetration but greater "flammable" effects if does penetrate you may not wind up driving the enemy from the field in the first place.



Again, I agree totally. I think HE content was a complete waste in AP shells. I think the British approach of using shot was far better, and had many advantages. Still, many tank crews like to make sure their target is destroyed, and not playing possum, I hold the same view - if it's an inferno, this would be a lot easier. Still, with the low range and performance of Soviet guns, this would not be such a problem?



> In General (and there are more than a few cross overs) Field Guns use fewer different powder charges (to adjust for range) and have higher velocity. Some feild guns (75mm) use fixed ammo with non-adjustable powder charges.



Whoah, complicated! There would be crossovers! lol: What would you classify the 75mm M3 as BTW? (I call it a D-P tank gun).

A lot of sources refer to the A-19 ( D-25 variant) as gun-howitzers, which confuses me. I found this:



> Because of good elevation, in contemporary documents the gun was often referred to as gun-howitzer.



- on here: Reference for 122 mm gun M1931/37 (A-19) - Search.com)



> 128 was intended to be a general purpose gun, replacing the 10cm field gun (not howitzer) which was thought too heavy for the weight of shell it used and more range was wanted too.



What was the 10cm field gun? Do you have a link? Thanks, you've also jogged my memory  - the Germans apparently came up against the Soviet 122mm, were impressed, and wanted an equivalent. Its HE peformance must've been felt to be unnecessary though? - as the Sturer Emil was cancelled.



> Shatter was a problem at somewhere between 2000-2600fps depending on projectile (and heat treatment) armor (and heat treatment) and which source you believe. Steel APDSFS might be in trouble at any practical range because the idea behind (or at least one of them) is that the APFSDS projectile slows down the least amount with range.



I can't remember the max effective range of the 50mm L60 vs the T-34/KV, using normal PzGr 39, but I think that at this distance, the MV with APFSDS should have fallen below the 2,000-2,600fps (thanks!) shatter threshold? Below that, even the PzGr would have shatter problems - but the PzGr 40 shouldn't (which was the most used anyway). I wonder if this would reduce PzGr 40 usage at all? - I'd expect so, and allow kills at less scary ranges.



> Trying to marry the two doesn't work. the starting requirements for the two are too far apart. The Flak gun needs fixed ammo (shell crimped into cartridge case) to obtain a high rate of fire. The howitzer needs separate ammunition because it needs to be able to adjust the powder charge from low to high in order to cover the full range of targets, like lobbing a shells over a ridge and into the valley just beyond. A Flak gun would not only shoot over the ridge but the entire valley and maybe the the next ridge
> Howitzer barrels also lasted much longer than flak barrels, mostly because they used much less powder per shot, low charge levels caused almost negligible wear but use of full or super charges had to be carefully noted in log books and sometimes came with restrictions on how many could be fired in a row.
> 
> also see the weight difference between the 10.5 cm leFH 18 and the 10 cm schwere Kanone 18, a little under 2000kg compared to over 5,500kg. for just about the same shell.



I was thinking of a desperate hybrid - as so often happened with German AT arty. I would use the Flak ammo and barrel, the leFH18 carriage (or other - but not necessary on a vehcle). As for HE - I'd use it as a purely long-range weapon so keeping the flak ammo, with maybe a slightly different HE shell (a good idea?). I don't know if new sights would be needed, or if the others could be adapted? Weight would be an issue, but a lot of the complex flak parts could be discarded/replaced.


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## schwarzpanzer (Apr 12, 2010)

Sorry, another 2-parter: (are these a problem?). My post counts gonna be through the roof! 

Hi tomo,



> If you mange a hit with HESH, there is no need to hit it time and again - you know that it represents hardly any threat, so you can move on to the another target.



How could you know for certain though? If you hit it though, I suppose you could assume it was finished? (still too risky though, IMO).



> There is many anecdotes that go this way: Allied tank gets knocked down, crew escapes, returns to the tank park and then returns to the front line with a brand new M4.



That's true. With a resource-rich enemy.

Thanks for the infos. A lot to take in there! 8)



> The 'gun-howitzers' are suppose to embrace the best from both worlds, and form the bulk of modern field artillery park. Russian ML-20 (152mm) offered almost twice the shell weight compared with A-19 (122mm), while being of same weight. The range reduction was some 20%, and, since it out-ranged the 99% of German field artillery pieces, they continued it producing in numbers.



Yes, the ML-20 was a beauty. It's whats got me into bigger guns. It's superiority is apparently why the Germans developed the Rochling shells.



> The shortcoming was that it weighted twice as 152mm howitzer, for same shell weight; range was some 12km vs. 17km for ML-20.



There was a dedicated 152mm howitzer? Any more info please? 



> The British 25pdr 5,5in could be also regarded as gun-howizers.



I know the 25pdr - grew up with it, so thats OK!



> It was trialed at captured French Russian carriages, so perhaps they were intending to use it as a towed piece?



Thats the 2nd time my memories been jogged - yes, I remember! What was it's intended role there? DP, HE or AT? What was it called? - PaK 44? - if so, that just screams ATG.



> A-19, while indeed a jack-of-all-trades, was pretty good in all of them, but certainly the newer 128mm was offering come advantages in sheer power sights.



Yeah, I think it would be slightly unfair to compare the two - even though, and funnily enough especially, because the PaK 44 (?) was based on the A-19. To be honest, I think the A-19 and variants were pretty poor weapons (? - or just used badly?). Still, good in 1943 against Tigers/Panthers though.



> No probs - the constructive talk about weaponry is at my liking
> I'm in artillery as in any piece of militayry hardware, but arty doesn't catch any limelight (=topics).



Me too, though I wasnt that into heavy arty, till recently.



> Guess we'd need some really good info about steel AP ammo vs. modern armor



If I see anything in future, I'll post it on here (unless its illegal). The basis is this though: LRPs (Long Rod Penetrators) are thin - which modern armour breaks up (snaps it like a pencil!). Full-calibre rounds (especially 120mm+ ones) arent so vulnerable to this happening.



> Yep, too bad T-62 was just 'another T-54/55' IMO, but it's main shortcomings were sights other fancy (but useful) stuff Western tanks have had.



The T-62 was actually very different (dimentionally, at the lowest level). However, it took the T-54 design philosophy too far - the opposite of the KV-1, infact. The main problem was with the reloading IMO, and the fact that it led (by accident) to the Type-69.



> I guess you've heard many stories about Typhoons P-47s blasting German tanks. That was exaggeration, but, when they managed to blast their supply trucks (carrying ammo among other stuff), that was almost equal as if they were blasting the tanks themselves.
> So, if your (German) tank unit has 90 round per tank, there was nothing wrong with that.



Sorry, what I wrote got screwed  - shoulda checked. Typhoons vs tanks is a subject that interests me btw, and is a good point... (blast effect). Why was it exaggeration btw?

I suppose having 90 rounds is good for emergencies, but it makes the tank bigger and/or more likely to brew up, and late war, they would have no chance of fillin such massive stores (?). Then again, some sources put T-34 ammo stores @ 80, will have to check... That was for a DP gun though...



> Too late
> As for 40-50 ton vehicle, they've just needed to copy KV (but with 8,8 in turret) an be done with that.



They kinda tried that (the Tiger). The Germans couldn't get the alloys the Soviets could though, and though the initial engine in the Tiger was alu (the Maybach HL 210), this couldn't go on forever - and it had to be replaced with the iron HL 230 (which was probably better). Also, they couldn't use diesel (it was reserved for the Kriegsmarine) and I don't know if they could make an alu diesel (has anyone since??). The steel roawheels on the KV impressed the Germans though - and they copied them. However, they apparently didn't work so well when large diameter. If the Tiger had used KV suspension though ( sloping armour), then it would've been cool IMO - and about what you suggested. Still, not German enough eh? - Can't be seen to copy the Untermenche?



> With 105 150 you have ready pieces to take it on Russkies, while 128mm was pretty rare, and not really embraced by Army during WW2. But with orders being of right timing, there is no doubt that 128mm would've be available in numbers to supplant both calibres.



So you think it could do it? It's hard though, isn't it. The Soviets kept all 3 calibre 'classes' (- only replaced the 122mm with the 130mm?). Would this be possible for Germany? - or desireable?



> You mean 10,5cm leFH18? I guess any hit from that at T-34 would've been quite a nuisance
> I guess mating leFH carriage with Tiger's cannon would've been easy, but that would have been just another towed AT gun.



Yes, sorry! I know the FH18 was 150mm btw, sorry (not 155mm!  - so confusing!). I wonder if the *le*FH18 () could destroy a T-34 beyond AP range with HE? I've got a simulator that can test this, but I got wiped out last time I tried it. Dont remember using HE - but I'm no good with heavier Arty (btw I later changed to a flak 88 and had my revenge!). 

I meant the leFH flak 105, but that would work too! (or the KwK 42...). Just another towed gun?? - THE towed gun!

Does anyone know if the Flak 105 ever fired at tanks? IIRC the 128mm did, at the Berlin Zoo?



> The necking-up also includes the wider barrel to accommodate the wider projectile.
> The 3,7cm Pak was using the usual barrel standard cartridge (minus the projectile) in order to fire a huge round that was attached to the muzzle - something like rifle grenades used even today. That was NOT necking-up though.



Now you brought it up, I can think of lots of necking-up examples. Obvious really, though it never occured to me - doh! I thought it was only important in infantry weapons really - like the 9mm PB (a necked-up 7.65mm). 



> The MV that got 'ruined' was still enough to enable white phosphorus shells to be fired from 75mm - guess you wouln't like to be on receiving end of that.
> BTW, 'soft' targets were more likely to be encountered from Normandy on, than Panther al, so 75mm was pretty good choice.



Were WPs available for the QF 75mm? Were they good against tanks? Thats true on the second part - but by this point Cruisers needed splitting again, as before (battle support). The battle variant would need the 17pdr/77mm IMO, you cant just not have one?? Wouldn't the M3 gun ( possibly Sherman turret with it) have been much better? I suppose the QF was able to deal with the pre-Ausf G Panther, in theory, but still...



> With everybody in agreement, we'd have nothing to discuss



Ah, if only more people thought like you, I think the world would be a much better place.


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## tomo pauk (Apr 12, 2010)

schwarzpanzer said:


> Hi tomo,
> 
> How could you know for certain though? If you hit it though, I suppose you could assume it was finished? (still too risky though, IMO).



Guess only experience would've tell - my money is on the HE/HEAT/HESH 



> Yes, the ML-20 was a beauty. It's whats got me into bigger guns. It's superiority is apparently why the Germans developed the Rochling shells.



ML-20 is still very much an useful weapon 


> There was a dedicated 152mm howitzer? Any more info please?



Two main types:
-M-10, produced from 1939-43, 4-4,5 tons,
-D-1, mating carriage of 122mm howitzer with 152mm barrel muzzle brake, from 1943, under 4 tons
Ranges cca 12 km.


> Thats the 2nd time my memories been jogged - yes, I remember! What was it's intended role there? DP, HE or AT? What was it called? - PaK 44? - if so, that just screams ATG.



I'd have to agree with Shortround6 - it was more of an all-arounder, rather than a dedicated AT gun (nomenclature notwithstanding). Wiki entry mentions the captured carriages.



> Yeah, I think it would be slightly unfair to compare the two - even though, and funnily enough especially, because the PaK 44 (?) was based on the A-19.



Don't think it was based on A-19 


> To be honest, I think the A-19 and variants were pretty poor weapons (? - or just used badly?). Still, good in 1943 against Tigers/Panthers though.



When talking about Russian artillery:
never never ever describe Russian artillery as 'pretty poor weapons' - their artillery park was far better than German IMO. 



> If I see anything in future, I'll post it on here (unless its illegal). The basis is this though: LRPs (Long Rod Penetrators) are thin - which modern armour breaks up (snaps it like a pencil!). Full-calibre rounds (especially 120mm+ ones) arent so vulnerable to this happening.



That's why I'm ringing the HE/HESH/HEAT bell... 



> The T-62 was actually very different (dimentionally, at the lowest level). However, it took the T-54 design philosophy too far - the opposite of the KV-1, infact.



The T-62 can track it's lineage back to T-43, but not with KV series 


> The main problem was with the reloading IMO, and the fact that it led (by accident) to the Type-69.



Not mixing T-62 with with T-64, don't you? 



> Sorry, what I wrote got screwed  - shoulda checked. Typhoons vs tanks is a subject that interests me btw, and is a good point... (blast effect). Why was it exaggeration btw?



It was stated that Typhoons used their rockets to destroy AFVs, while the real accuracy of rockets was on order or two less than cannons, ie. hardly able to hit a tank in combat conditions (check "The best tank-busting plane" in the Aviation sub-forum for reference).


> I suppose having 90 rounds is good for emergencies, but it makes the tank bigger and/or more likely to brew up, and late war, they would have no chance of fillin such massive stores (?). Then again, some sources put T-34 ammo stores @ 80, will have to check... That was for a DP gun though...



German past-1942 tanks were big vehicles with moderate sized guns, so such an ammo count was easy to achieve.



> They kinda tried that (the Tiger).



No relation what so ever - KV series were very simple vehicles, with sloped armor, 'all-aft' power pack etc. Plus, Tiger was being designed before Germans encountered KVs, even before attack vs. France.



> The Germans couldn't get the alloys the Soviets could though, and though the initial engine in the Tiger was alu (the Maybach HL 210), this couldn't go on forever - and it had to be replaced with the iron HL 230 (which was probably better). Also, they couldn't use diesel (it was reserved for the Kriegsmarine) and I don't know if they could make an alu diesel (has anyone since??).



IIRC, they've made the decision to go all-gasoline prior the war, even though diesel is easier to come by, and it's cheaper to produce.
Either alu or steel engine, they should have mounted the gearbox in aft part of tank. That way one saves volume (major issue in tank design) - therefore saving on weight of armor for same level of protection. Plus, tank presents smaller target.


> The steel roawheels on the KV impressed the Germans though - and they copied them. However, they apparently didn't work so well when large diameter. If the Tiger had used KV suspension though ( sloping armour), then it would've been cool IMO - and about what you suggested. Still, not German enough eh? - Can't be seen to copy the Untermenche?



Not Tiger, but Panther would've been KV-like 
The rasisticaly-based decisions of German leadership backfired in their face many times in past.



> So you think it could do it? It's hard though, isn't it. The Soviets kept all 3 calibre 'classes' (- only replaced the 122mm with the 130mm?). Would this be possible for Germany? - or desireable?



Possible? Sure.
Desirable? Don't know 



> Yes, sorry! I know the FH18 was 150mm btw, sorry (not 155mm!  - so confusing!). I wonder if the *le*FH18 () could destroy a T-34 beyond AP range with HE? I've got a simulator that can test this, but I got wiped out last time I tried it. Dont remember using HE - but I'm no good with heavier Arty (btw I later changed to a flak 88 and had my revenge!).



There is 15cm sFH18, and then there is 10,5cm leFH 18 
We'd need to dig further for anti-tank performance of 10,5cm howitzer.



> I meant the leFH flak 105, but that would work too! (or the KwK 42...). Just another towed gun?? - THE towed gun!



10,5 Flak would've overloaded the 10,5 howitzer carriage; the 8,8L71 was the biggest ordnance that carriage would've accepted without much trouble IMO. Surely, the 7,5L70 was very much feasible - but indeed just another towed gun 



> Does anyone know if the Flak 105 ever fired at tanks? IIRC the 128mm did, at the Berlin Zoo?



Anyone?



> Were WPs available for the QF 75mm? Were they good against tanks?



IIRC, yes on bot accounts.


> Thats true on the second part - but by this point Cruisers needed splitting again, as before (battle support). The battle variant would need the 17pdr/77mm IMO, you cant just not have one?? Wouldn't the M3 gun ( possibly Sherman turret with it) have been much better? I suppose the QF was able to deal with the pre-Ausf G Panther, in theory, but still...



You've thrown too much cannons for Cruisers to mount here  British tanks their main armament deserve a thread on its' own...


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## Vincenzo (Apr 12, 2010)

Tomo for AT use of field artillery i read italian report from soviet front where it's writed that italian field 75mm was good versus soviet light tank (not specified ) and field 100mm was good versus T-34 in both cases with both ammos (AP and HE)


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## tomo pauk (Apr 13, 2010)

The Italian field 75mm gun(s) have had comparable muzzle energy as the 'French 75'/US 75mm, or Russian 76,2mm (from T-34 KV1), so I think it was pretty good in AT job; having 100mm hitting the T-34 was not pleasant for the tank either


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## schwarzpanzer (Apr 13, 2010)

Hi Vincenzo,

Even 20 37mm's were good against Soviet light tanks!  If it's Italian guns, then the Breda 20 47mm too.

I take it you were meaning with HE though? - I wonder if a 47mm would be enough for, say a T-26?... 

Did the Italians have a 100mm? Any info please?


Hi tomo,



> Guess only experience would've tell - my money is on the HE/HEAT/HESH



I would still not be happy. Was thinking though, with what someone on here suggested: HE HEAT only (forget HESH). Fire HE until the vehicle is disabled (unlike with HESH (?), indirect hits could still disable). Then, to be sure, follow up with a well-aimed HEAT. HEAT has both excellent penetration and incendiary qualities - perfic! Spaced armor might cause problems though... Though the HE rounds may have ripped that off. If that Hl/C was available, that would likely have done the trick. Also, I tried working out expected penetration for this round, and came out with a (conservative) estimate of 244mm.

I suppose if the turret came off like a jack-in-the-box, then you would know it was finished.  - but could this happen with HE shells? (a 150mm on an IS-3).

The ML-20 is still in service? Then again, heavy arty tech hasn't changed much since WW1? (excepting Metal Storm maybe). Seems to go with my thinking of concentrating research on ATGs ammo, rather than heavy arty. Any info on heavy arty development would be appreciated.

Thanks for the D-1 info. I think I've seen that before - but just figured it to be a cheapo ML-20. Now I know the truth. Thanks again! 



> I'd have to agree with Shortround6 - it was more of an all-arounder, rather than a dedicated AT gun (nomenclature notwithstanding). Wiki entry mentions the captured carriages.



Yes. Infact, I think I've figured out it's quirks - it was meant to be the German A-19, so was to be a HE-firer, with AP a secondary function. This would explain the shorter barrel split-loading case. When it became a PaK though, I think these features should have been changed, but that would delay it, still it wasn't too popular as a field gun anyway, but would make a great PaK. I think it was originally called the K 44, or similar - showing it was dual-role. All of this is available in the Wiki entry! (IIRC my info came from Ian Hogg, but was forgotten - till you refreshed it, thanks!). It wasn't based on the A-19 as such - but you know what I mean! 



> When talking about Russian artillery:
> never never ever describe Russian artillery as 'pretty poor weapons' - their artillery park was far better than German IMO.



Their HE stuff yes, but not their ATs, not by a long shot IMO. I also think the Germans had some decent stuff (but we are analysing them here - in minute detail!).



> That's why I'm ringing the HE/HESH/HEAT bell...



HESH and HEAT will not work on modern armour - though Soviet research on triple-charge HEAT Warheads is apparently impressive. HE can disable a modern MBT, and disable or weaken the modern armour. HESH is now useless however - modern armour is composed of @ least 3 layers: outer (such as Chobham, ERA, or both), normal steel (which I think is malleable anyway - reducing spalling) and finally a spall liner - so HESH is no longer useful against MBTs, but maybe lighter vehicles and bunkers. HESH was good for it's time though, apart from the possible ignition problems I mentioned.



> The T-62 can track it's lineage back to T-43, but not with KV series



I meant that the KV-1 was too much tank for the gun, the T-62 was the opposite. Other Soviet vehicles fit into these categories (IS-1 IS-2, for e.g.).



> Not mixing T-62 with with T-64, don't you?



Funnily enough, I don't mix the two (because I think chassis-biased), though do with others all the time (especially light tanks). The Type-69 was a Chinese tank, based on the Type 59 (a legit T-54 copy), with upgrades filched from a T-62 captured in the Sino-Soviet War. It was the most common Iraqi tank in the Gulf Wars. What is confusing to me is that Type 69 can mean lots of things, like M4.



> (check "The best tank-busting plane" in the Aviation sub-forum for reference).



I will do that, thank you.



> German past-1942 tanks were big vehicles with moderate sized guns, so such an ammo count was easy to achieve.



True, but they had poor internal layout - both mechanically, and in regard to stored munitions - it's about quality ( yes, I admit, a little about quantity). The E-Series seemed to change this though...



> No relation what so ever - KV series were very simple vehicles, with sloped armor, 'all-aft' power pack etc. Plus, Tiger was being designed before Germans encountered KVs, even before attack vs. France.



The KV was not that simple - it had an alu, DOHC, 4v/cyl diesel. It's armour wasn't exactly sloped - more like angled (but then, so was the Tigers). I know the Tiger was designed before experience with the T-34 KV - but they altered the design requirements slightly (armour up from 80mm to 100mm, to keep out that 76mm) and possibly also larger roadwheels. What I meant was if the suspension of the KV had been copied - the other mechanicals would not be practical, except maybe an all-aft powerpack (but I think the Transmission was finalised with the VK3006H?).



> IIRC, they've made the decision to go all-gasoline prior the war, even though diesel is easier to come by, and it's cheaper to produce.



Is that true? Thanks, some more good info - keep it coming!



> Either alu or steel engine, they should have mounted the gearbox in aft part of tank. That way one saves volume (major issue in tank design) - therefore saving on weight of armor for same level of protection. Plus, tank presents smaller target.



I also thought this, but an aft gearbox has its disadvantages: 1. Harder controls - fore trans can even use an open-gate shifter 2. Damage - it requires connector cables, which are often fragile 3. I don't agree with this one, but there is a school of thought that says it adds extra protection, after the armours been penetrated (this is totally countered by my last point on aft trans advantages, @ the end of this paragraph). Another advantage of aft transmissions (for me) is that it is the idler wheel, rather than the drive sprocket that is more likely to get damaged. Also, with more weight @ the back, more armour can go on the front.



> Not Tiger, but Panther would've been KV-like



Are you talking purely weight? I was meaning mechanically. Inter-nation classification is funny - the Germans called the Panther a Medium, the Soviets a Heavy. The Soviets called the IS-2 a Heavy, the Germans a Superheavy. 



> The rasisticaly-based decisions of German leadership backfired in their face many times in past.



Yes, but it was not Hitlers fault - he apparently wanted the more Soviet Panther design, but was overuled (again!). He ranted about this at the end of the War (along with other things ). I think the worst ting they did was refuse to adopt American production methods - or was it?...



> Possible? Sure.
> Desirable? Don't know



Yes, its a toughie isnt it? - another one to ponder: 1 gun, 2 guns, or 3?... I'm sure we'll find the answer! (?)



> There is 15cm sFH18, and then there is 10,5cm leFH 18



AARGH! Next you'll be telling me there was also an mFH18 FH18? - Can't I just go back to calling it an 155mm? I know theres an SIG and LeIG too, so confusing!



> We'd need to dig further for anti-tank performance of 10,5cm howitzer.



IIRC the HE shells had a higher velocity - so should be better for long-range AT work? From what Vincenzo has said, the 105mm HE shells should wreck a T-34? (what about a KV?). IIRC the AP rounds were useless untill well below 500m - suicide distance, and with such heavy amoo, no hope for a reload. They also weren't PzGr 39 (APCBC/HE), or PzGr 40 (APCR), but either APC or plain AP (dunno about HE content). Can check, if you want? APC is OK for close-range work though (but APCBC would still be better).



> 10,5 Flak would've overloaded the 10,5 howitzer carriage; the 8,8L71 was the biggest ordnance that carriage would've accepted without much trouble IMO.



Thanking you, that was the info I was after! - though way to kill my idea!



> Surely, the 7,5L70 was very much feasible - but indeed just another towed gun



THE towed gun! (untill the PaK 43).

Thanks for the QF 75mm WP info. Any more?



> You've thrown too much cannons for Cruisers to mount here British tanks their main armament deserve a thread on its' own...



Nah, excluding Lend-Lease stuff, there was only (IIRC):

Battle:

2pdr, 6pdr 77mm

Support:

3 3.7in



> Dual-Role:



75mm

- there was an experimental 75mm Battle, but I'll leave that out, as it never saw combat (?).

If I say 'Battle Gun', instead of 'ATG' thats better, isnt it? 



> The Italian field 75mm gun(s) have had comparable muzzle energy as the 'French 75'/US 75mm, or Russian 76,2mm (from T-34 KV1), so I think it was pretty good in AT job;



Good info - are we bringing Italians into the mix as well?? - this is gonna be a loong discussion!



> having 100mm hitting the T-34 was not pleasant for the tank either



I bet it wasnt!  - especiallly with that brittle armour.



> Quote:
> Does anyone know if the Flak 105 ever fired at tanks? IIRC the 128mm did, at the Berlin Zoo?
> 
> Anyone?



Anyone at all??  Someone else requested similar just recently, I think?


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## Shortround6 (Apr 13, 2010)

T-26 and any other of the older light tanks were pretty much gone by the winter of 1941, although with thousands of tanks a few lingered on. The T-60 and T-70 could be knocked out with light guns but hoping the Russians are kind enough to attack with tanks that match your light weapons is asking a bit much


244mm of armor is practically battleship stuff. 

There is a reason people issued AT rounds to field guns. HE doesn't work that well against tanks. Unless it is very large. 
See AP rounds for the German 10.5cm howitzer or solid shot for the British 25pdr. IF HE worked why bother?


British doctrine for the 5.5in (140mm) was to fire the standard 100lb HE shell with a full charge WITH THE FUSE REMOVED AND THE TRANSPORT PLUG IN PLACE.

I don't know if they ever had to use it in combat but they figured the impact could lift a turret right out of the hull even if it didn't penetrate. 

Artillery did most of the killing in WW II. Opinions differ on the exact percentage but most attacks and defenses depended on artillery and lots of it. AT work was a side line.

Once again, separate ammunition is easier to load when power assistance isn't available. And it wasn't available on WW II towed non-AA guns, and those sometimes needed a separate generator cart/truck. 

Separate ammunition also makes ammo storage/inventory easier. For AT work you just need the projectiles. Load projectile and shove standard cartridge case with appropriate powder charge in behind it. with fixed ammo you have to lug around/store the projectiles with that wacking big cartridge case crimped to it at all times. 

Modern armor has little (or nothing) to do with WW II armor or the projectiles needed to defeat WW II armor. HE could be somewhat effective in getting mobility kills against WW II tanks (blowing off/breaking tracks and road wheels) but again, unless it was very large it chances of getting a total kill were small.

If enemy tanks are engaging your heavy artillery (over 105mm)with direct fire one of two things has happened.
1. things have really gone to SH_T and headquarters better think about bugging out. heavy artillery normally being a number of kilometers behind the front line.
2. Your side has such an abundance of heavy artillery it can afford to put it in/near the front line were it can be counter battery fired by anything bigger than a popgun. Getting 122-152mm artillery pieces knocked out by 81-120mm mortars means a really bad disposition of equipment.

German 10.5mm howitzer AP rounds might just cope with a T-34, with a lot of luck. at 1000yds they just about matched the penetration of the Pak 50mm. at shorter ranges the Pak 50 did better and at longer ranges the Howitzer penetrated more than the Pak 50 (which isn't saying much really). Problem is that the Howitzer had such a low velocity that getting hits at such long range wasn't going to be easy.


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## schwarzpanzer (Apr 14, 2010)

Hi Shortround,



> T-26 and any other of the older light tanks were pretty much gone by the winter of 1941, although with thousands of tanks a few lingered on. The T-60 and T-70 could be knocked out with light guns but hoping the Russians are kind enough to attack with tanks that match your light weapons is asking a bit much



Apparently, it was the most common tank - along with the equally feeble BT-series. True 1940s Medium and Heavies caused havok though - and I would also argue that the BT T-26 were stll dangerous opponents. Both had faced each other before though, in the Spanish Civil War, and had acheived parity there too (with the Soviet tanks having a slight upper hand). In Barbarossa though, the PzIIs front armour was upgraded to 35mm, and the Pzs III IV were also appearing. The Germans were only really inferior from Autumn (fall) 1941 to late 1942 - only about a year. I think though that '44-'45 is debatable though...



> 244mm of armor is practically battleship stuff.



Dont think HEAT would work well against a Battleship? The IS-3 only weighed only 45 tons (the same as a German Medium - though that is debatable) and, depending on the source, had 220-280mm. 



> There is a reason people issued AT rounds to field guns. HE doesn't work that well against tanks. Unless it is very large.



British Cold War doctrine held that Chemical, rather than Kinetic Energy was the best way to deal with tanks. In WW2, I would say it wasn't, but I think tomo thinks it was (we're right in the middle of discussing it). It depends on the armour qualiy of the opponents - tin armour (as on the T-26) or that prone to spalling (like the ISs) would be very vulnerable to CE attack. However, as I mentioned reently, HE doesn't cause fires (but apparently can against light armour, such as that found on the T-26).



> See AP rounds for the German 10.5cm howitzer or solid shot for the British 25pdr. IF HE worked why bother?



I've only just mentioned this - it was the lack of being able to start fires. Penetration is apparently the best way to defeat armour though (depending on the source). As a side not, Tigers often fired at M10 Wolverine TDs with HE, rather than AP (which would pass straight through, causing little damage). The same is probably true of any open-topped/backed vehicle. I suppose what I'm tring to say is, it basically depends on the target - some AFVs respond better to treatment usually reserved for 'soft' targets ( visa-versa).



> British doctrine for the 5.5in (140mm) was to fire the standard 100lb HE shell with a full charge WITH THE FUSE REMOVED AND THE TRANSPORT PLUG IN PLACE.
> 
> I don't know if they ever had to use it in combat but they figured the impact could lift a turret right out of the hull even if it didn't penetrate.



Thats interesting. At what time period was this? Again though, I suppose it really depends on the target.



> Artillery did most of the killing in WW II. Opinions differ on the exact percentage but most attacks and defenses depended on artillery and lots of it. AT work was a side line.



Is that true? Be interesting if it is. Guderian did criticise the Tiger over the Panther for this though. I've only just started lumping the 2 together! - Now I have to change back?! This is a debate in itself (Battle Support, or DP alone?) which I think we've touched on here a short while ago? 



> Once again, separate ammunition is easier to load when power assistance isn't available. And it wasn't available on WW II towed non-AA guns, and those sometimes needed a separate generator cart/truck.



I don't think a 128mm would be loadable by a single loader? Then again the single-piece one on the Sturer Emil apparently was. By this point though, 2-loaders for the 128mm were the norm. This might affect personnel, but could be worked around... I suppose you cant crew a 6-crew tank, if you cant crew a 5-man one (as happened to some KTs). Why the seperate generator? The pre-Ausf J PzIV had a seperate generator ( IIRC so did the others). These vehicles would be rare though, as they were intended to fight tanks that were also relatively rare clumsy (the IS-3-10).



> Separate ammunition also makes ammo storage/inventory easier. For AT work you just need the projectiles. Load projectile and shove standard cartridge case with appropriate powder charge in behind it. with fixed ammo you have to lug around/store the projectiles with that wacking big cartridge case crimped to it at all times.



Thats a good point, but I don't think it would be that much of a difference? - you would have even more confusion IMO having different charges. With single-piece ammo, yellow/green = HE, black = AP, simple? I'm having difficulty explaining myself on this one, but I have thought it through before! Also, to move, say 40 rounds, you would need to make 40 repetitions with single-piece ammo, but 80 with split-load - enough to get RSI?! How much extra does a 128mm projectile weigh though, 60pounds? - OK, I admit thats heavy!



> Modern armor has little (or nothing) to do with WW II armor or the projectiles needed to defeat WW II armor.



True, sorry,  but I threw that in the mix to illustrate how older AP projectiles can work against modern armour, where LRPs (Long-Rod Penetrators) will not. Like in the way, apparently, WW2 Radar will also pick up Stealth aircraft.



> HE could be somewhat effective in getting mobility kills against WW II tanks (blowing off/breaking tracks and road wheels) but again, unless it was very large it chances of getting a total kill were small.



It depends (as it does to a degree with KE) on the relationship of the size of the gun, and/or efficiency of the CE shell to the thickness, /or quality of the targets armour. Whether 150mm HE shells would cause spalling on an IS-3 though?... (pleease dont tell me this has already been answered?). American armour was very malleable (the best in WW2 apparently), so not so vulnerable to spalling. But, at times the thin armour on the Shermans sponsons was hit by HE shells -which cased the poorly stored ammo to blow. Another point is that Soviet ammo was less stable, and easy to set off with a glancing blow, or HE shell.



> If enemy tanks are engaging your heavy artillery (over 105mm)with direct fire one of two things has happened.
> 1. things have really gone to SH_T and headquarters better think about bugging out. heavy artillery normally being a number of kilometers behind the front line.



True, but some arty was for frontline use - such as that on the PzIV, Stug StuH. The 150mm I suggested as a desperate measure - as what happened with the LFH18 Flak 88 - both not intended for AT work, but both pressed into service in that role (though by WW2 both of them were expected to fight armour, hence the AP rounds). Soviet arty was also expected right from the start to engage tanks: the 85mm Flak ML-20, for example.



> 2. Your side has such an abundance of heavy artillery it can afford to put it in/near the front line were it can be counter battery fired by anything bigger than a popgun. Getting 122-152mm artillery pieces knocked out by 81-120mm mortars means a really bad disposition of equipment.



True, counter-battery fire is bad. The Flak was also vulnerable to the Soviet 76mm US 75mm of their tanks, as it wasnt low-slung like the purose-built PaKs. Also, it is vulnerable to infantry/snipers/grenades etc on the front line. The flak 88 eventually morphed into the PaK 43 though, as would 128 150mms, eventually (though it seems vehicle mounting is the only option for these 2 monsters). These were desperate measures though, I also appreciate that bringing up non-purpose-built, heavy towed arty is difficult.



> German 10.5mm howitzer AP rounds might just cope with a T-34, with a lot of luck.



Not ideal, but better than the 37 and short 75mm (though the latter could use HEAT effectively, and the former could maybe use PPS APFSDS?).



> at shorter ranges the Pak 50 did better



That seems wrong to me - are you talking pure penetration performance? Then again, the PaK 38 could fire PzGr 40 APCR (which had serious repurcussions later). Also, it had a higher RoF, could track targets better and had a lower silhouette - as it was designed purposely for this role (but was actually worse all-round IMO).



> and at longer ranges the Howitzer penetrated more than the Pak 50 (which isn't saying much really).



Every little helps. The PaK 38 could deal with a T-34 at 1km, but that is too close for comfort (about parity). The LFH18 could destroy, or at least disable a T-34, whilst being immune itself. Also, a hit at <1km would be less likely to be deflected or shattered on the T-34s armour. Unlike the PaK 38 though, it would not be likely to get a 2nd chance if the T-34 missed its shot.



> Problem is that the Howitzer had such a low velocity that getting hits at such long range wasn't going to be easy.



Thats true. Indirect hits could disable though - allowing for a well-aimed follow-up finishing shot. Also, indirect disabling could, in theory at least, disable several T-34s in a single hit...

A similar case is with the short 75mms.


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## Shortround6 (Apr 14, 2010)

schwarzpanzer said:


> Apparently, it was the most common tank - along with the equally feeble BT-series. True 1940s Medium and Heavies caused havok though - and I would also argue that the BT T-26 were stll dangerous opponents. Both had faced each other before though, in the Spanish Civil War, and had acheived parity there too (with the Soviet tanks having a slight upper hand). In Barbarossa though, the PzIIs front armour was upgraded to 35mm, and the Pzs III IV were also appearing. The Germans were only really inferior from Autumn (fall) 1941 to late 1942 - only about a year. I think though that '44-'45 is debatable though....



The T-26 and the BT series were pretty much out of it by the winter of 1941. Killed captured or abandoned. And they could be handled by anything bigger than a 20mm. No need for super tanks or super ammunition. 




schwarzpanzer said:


> Dont think HEAT would work well against a Battleship? The IS-3 only weighed only 45 tons (the same as a German Medium - though that is debatable) and, depending on the source, had 220-280mm.


It works like crap against a battleship. Vital parts are too far from the side armor for the penetrating jet to do any real damage and interior volume is to big to get any over pressure from the penetrating jet. also think of compartment walls as spall liners. 

IS the 220-228mm if armor the real thickness or effective thickness. or just a few square feet right around the gun mount?




schwarzpanzer said:


> British Cold War doctrine held that Chemical, rather than Kinetic Energy was the best way to deal with tanks. In WW2, I would say it wasn't, but I think tomo thinks it was (we're right in the middle of discussing it). It depends on the armour qualiy of the opponents - tin armour (as on the T-26) or that prone to spalling (like the ISs) would be very vulnerable to CE attack. However, as I mentioned reently, HE doesn't cause fires (but apparently can against light armour, such as that found on the T-26).



Once again, comparing WW II HEAT performance to cold war HEAT performance is like comparing a Spitfire to a Hawker Hunter jet. A WW II 100-105mm gun was lucky if it's HEAT ammo could get 100mm of penetration (it took the Germans 4 different designs to get that far) by 1960 105 Heat rounds could achieve well over 200mm and the French 105 shell from the AMX 30 was supposed to penetrate 360mm. Smooth bore 90mm mounted on French armored cars could penetrate more than 300mm. Trying to mix and match performance of shells from 10-20 years apart only brings confusion. 




schwarzpanzer said:


> I've only just mentioned this - it was the lack of being able to start fires. Penetration is apparently the best way to defeat armour though (depending on the source). As a side not, Tigers often fired at M10 Wolverine TDs with HE, rather than AP (which would pass straight through, causing little damage). The same is probably true of any open-topped/backed vehicle. I suppose what I'm tring to say is, it basically depends on the target - some AFVs respond better to treatment usually reserved for 'soft' targets ( visa-versa).



you seem to have an obsession with setting tanks on fire. At the time this might have been considered a side benefit and not a requirement. Killing the crew and chewing up the equipment was usually considered good enough and if a quantity of very hot metal happened to land in an ammo rack and cause a few rounds to cook off so much the better but few people were going to sacrifice penetration (or much of it) for incendiary effects. Very thinly armored vehicles always presented a problem for for high powered guns. The fuses won't function on the APHE ammo.



schwarzpanzer said:


> Thats interesting. At what time period was this? Again though, I suppose it really depends on the target.


 WW II.



schwarzpanzer said:


> Is that true?[/QUOTE
> 
> It's true, try any work on Artillery.
> 
> ...


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## Vincenzo (Apr 14, 2010)

the 100/17 was the italian standard "heavy" (there were also 75mm howitzer) divisional howitzer, was a WWI pride from austrian ungarian empire. they are lightest but also with shorter range of modern 105mm howitzer (like U.S, german). 
here some data in italian Regio Esercito - Materiale bellico - Obice da 100/17 Mod. 1914


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## tomo pauk (Apr 14, 2010)

schwarzpanzer said:


> Did the Italians have a 100mm? Any info please?



(While not asked)
Czech/Austro-Hungarian 100mm M.1914; Poles have that one too. Both possesed also the 105mm (originally French) cannons - very usable even at end of 1945.


> Hi tomo,
> 
> I would still not be happy. Was thinking though, with what someone on here suggested: HE HEAT only (forget HESH). Fire HE until the vehicle is disabled (unlike with HESH (?), indirect hits could still disable). Then, to be sure, follow up with a well-aimed HEAT. HEAT has both excellent penetration and incendiary qualities - perfic! Spaced armor might cause problems though... Though the HE rounds may have ripped that off. If that Hl/C was available, that would likely have done the trick. Also, I tried working out expected penetration for this round, and came out with a (conservative) estimate of 244mm.
> 
> I suppose if the turret came off like a jack-in-the-box, then you would know it was finished.  - but could this happen with HE shells? (a 150mm on an IS-3).



If you aim to destroy an AFV with 250mm armor, why would you want to go symmetrical against that? Attack it from air, or aim for tracks/wheels, or make sure to deploy mines if you're on defense, don't hold the line in open field, but in intersected terrain (forest, bocage, towns, by rivers/streams/channels)...

You can't attack from air, since your enemy has advantage there? Then you have other stuff to worry, rather if super-duper tank is about to appear.


> The ML-20 is still in service? Then again, heavy arty tech hasn't changed much since WW1? (excepting Metal Storm maybe). Seems to go with my thinking of concentrating research on ATGs ammo, rather than heavy arty. Any info on heavy arty development would be appreciated.



While ML-20 is really useful, there is a lot of pieces that dwarf it, some being half as heavy able to move on their own at the battlefield, while firing guided projectiles 30km away...
There is lot to learn about the non-AT arty really 


> Their HE stuff yes, but not their ATs, not by a long shot IMO. I also think the Germans had some decent stuff (but we are analysing them here - in minute detail!).



Then you've should check out their 57mm At gun - the best towed AT gun of WW2, and the best AP performing tank gun 'till Kwk 36 arrived...


> HESH and HEAT *will not work on modern armour* - though Soviet research on triple-charge HEAT Warheads is apparently impressive.



Wrong there ("will not work" part) - check out the M1 Abrams cassualties in Iraq in this milenium, Merkava 4 adventures vs. Hezbollah militia.


> HE can disable a modern MBT, and disable or weaken the modern armour. HESH is now useless however - modern armour is composed of @ least 3 layers: outer (such as Chobham, ERA, or both), normal steel (which I think is malleable anyway - reducing spalling) and finally a spall liner - so HESH is no longer useful against MBTs, but maybe lighter vehicles and bunkers. HESH was good for it's time though, apart from the possible ignition problems I mentioned.



Chobham IS composed of steel, so methinks you'd need to delete the steel part from that. (I do bang my head for not buying the tank bible last year in Stuttgart, it was both tick cheap)
If the spall liner is able to withstand the hit of 20-40kg shell is still not well known for public IMO; I doubt it's THAT effective. 


> I meant that the KV-1 was too much tank for the gun, the T-62 was the opposite. Other Soviet vehicles fit into these categories (IS-1 IS-2, for e.g.).



KV-1 would've indeed put the 85mm/107mm in good use; too bad for Russkies they did that (85mm) in late 1943, in meagre numbers. IS-2 was tested with 100mm (of Naval origin; my favorite Russian gun), but 122 was far easier available.


> True, but they had poor internal layout - both mechanically, and in regard to stored munitions - it's about quality ( yes, I admit, a little about quantity). The E-Series seemed to change this though...



E-series? That's "panzer-46" stuff 


> The KV was not that simple - it had an alu, DOHC, 4v/cyl diesel.



But it's suspension layout of transmission were - Germans might have sticked with their Maybachs (if Russian engine was SO complicated  ) and be done with that. Those two advantages would've allowe for a more compact vehicle, with better protection for same weight, or less weight for same armor protection.


> It's armour wasn't exactly sloped - more like angled (but then, so was the Tigers). I know the Tiger was designed before experience with the T-34 KV - but they altered the design requirements slightly (armour up from 80mm to 100mm, to keep out that 76mm) and possibly also larger roadwheels. What I meant was if the suspension of the KV had been copied - the other mechanicals would not be practical, except maybe an all-aft powerpack (but I think the Transmission was finalised with the VK3006H?).



Again, we build this instead of Panther, not instead of Tiger.



> Is that true? Thanks, some more good info - keep it coming!



About the German decision or about advantages of diesel fuel?

I


> also thought this, but an aft gearbox has its disadvantages: 1. Harder controls - fore trans can even use an open-gate shifter 2. Damage - it requires connector cables, which are often fragile 3. I don't agree with this one, but there is a school of thought that says it adds extra protection, after the armours been penetrated (this is totally countered by my last point on aft trans advantages, @ the end of this paragraph). Another advantage of aft transmissions (for me) is that it is the idler wheel, rather than the drive sprocket that is more likely to get damaged. Also, with more weight @ the back, more armour can go on the front.



The advantages do overweight disadvantages - from late 30's till now.
If you want so badly the frontal gearbox, than you might take in consideration the engine position too, and move the engine in front, Merkava-style.



> Are you talking purely weight? I was meaning mechanically.



Both mechanically and by the weight.



> Yes, but it was not Hitlers fault - he apparently wanted the more Soviet Panther design, but was overuled (again!). He ranted about this at the end of the War (along with other things ). I think the worst ting they did was refuse to adopt American production methods - or was it?...



The folks from Daimler Benz were influenced by a _wrong_ Russian tank - they've should copied the KV...



> IIRC the HE shells had a higher velocity - so should be better for long-range AT work? From what Vincenzo has said, the 105mm HE shells should wreck a T-34? (what about a KV?). IIRC the AP rounds were useless untill well below 500m - suicide distance, and with such heavy amoo, no hope for a reload. They also weren't PzGr 39 (APCBC/HE), or PzGr 40 (APCR), but either APC or plain AP (dunno about HE content). Can check, if you want? APC is OK for close-range work though (but APCBC would still be better).



One thing is needed to convert the field gun into AT gun - the will (or order, if you prefer) to do that. 



> Thanks for the QF 75mm WP info. Any more?



You'd need to go to the tank-net.org to find out more - like I did 



> Nah, excluding Lend-Lease stuff, there was only (IIRC):
> 
> Battle:
> 
> ...



You're forgetting the 17pdr, plus 25pdr for SP arty...
I was not reffering to the plethora of guns, but to (your) requirement that Cruisers should have carried almost all of those.


> Good info - are we bringing Italians into the mix as well?? - this is gonna be a loong discussion!



New thread perhaps?


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## schwarzpanzer (Apr 14, 2010)

Hi Vincenzo,

Thanks for the link - but I don't understand Italian, or support arty for that matter!  Your brief description was brilliant though, thankyou. 8)


Hi Shortround,



> The T-26 and the BT series were pretty much out of it by the winter of 1941. Killed captured or abandoned. And they could be handled by anything bigger than a 20mm. No need for super tanks or super ammunition.



I was meaning the intitial stages of Barbarossa - Autumn (fall) if they were out of the picture by Winter, then yes. Not just above 20mm, but 20mm itself - also the 13mm 'Elefant' Anti-tank rifles! I know big guns weren't needed, I was just saying that fairly large HE shells would destroy these easily - however a KV would be apparently immune. According to some sources, it was safe from, IIRC 500lb bombs. It seems though, from what has been said on ere recently, that HE fire from a LFH18 105mm would destroy a T-34, internally (?). That I wouldn't have expected before.



> It works like crap against a battleship. Vital parts are too far from the side armor for the penetrating jet to do any real damage and interior volume is to big to get any over pressure from the penetrating jet. also think of compartment walls as spall liners.



Great info again. I was thinking that having a pencil-diameter hole wouldnt let enough water in t sink it, and that a fire wuldnt likely start. I know pretty much nothing about Naval gunnery - apart from that the Soviet obsesio with APHE came from there (esp. in the D-10). BTW, I wonder if you might know: were APCBC rounds 1st intended for anti-ship useage?



> IS the 220-228mm if armor the real thickness or effective thickness. or just a few square feet right around the gun mount?



Actual thickness. Effective thickness would likely be much higher, because it was sloped even more than that on the T-34 IIRC. I wondered if effective thickness is where the 280mm figure came from - but I expect it would actually bemuch higher than that! As someone said though, the Schuka made the structure either weaker or stronger, depending on the source shell used (CE or KE respectively - which would allow both sources to be pretty much correct). I dont know if overmatching relates to Actual Thickness, or Effective Thickness (?).

This is actually trickier than it seems, if you see the drawing on the previous page that hartmann posted, then you will see that both actual effective thickness is 220mm @ the bottom rear of the turret, but 'only' 110mm (or 140? - the writings hard to make out) of actual thickness just about everywhere else. I'm tempted to think these might be incorrect though, as I'm pretty sure the glacis was 120-160mm (as it was on the preceding IS-2), and the turret front had to be more than 110mm also?...

Also, hartmann said this:



> Seen the drawings, I only found a maximum thickness of 220 mm of casted steel in the turret (which would probably equivalent to some 190 mm of good rolled homogeneous armour)



So the production method would reduce the effectiveness too - or increase it, Soviet armour was not solidly interlocked, like on later, heavier German designs.

Also, Soviet armour was weird - usually hard, but brittle. It's a confusing subject - which probably explains why we're already @ 3 pages! Perhaps the IS-3 need a Thread of its own? - as it is central to these discussions. 



> Once again, comparing WW II HEAT performance to cold war HEAT performance is like comparing a Spitfire to a Hawker Hunter jet. A WW II 100-105mm gun was lucky if it's HEAT ammo could get 100mm of penetration (it took the Germans 4 different designs to get that far) by 1960 105 Heat rounds could achieve well over 200mm and the French 105 shell from the AMX 30 was supposed to penetrate 360mm. Smooth bore 90mm mounted on French armored cars could penetrate more than 300mm. Trying to mix and match performance of shells from 10-20 years apart only brings confusion.



That's true, but I wasn't comparing WW2 HEAT to Cold War HEAT. I was just saying that CE (Chemical Energy) Attack is a viable way to destroy tanks - as it was British Doctrine in the Cold War ( is only being fased out now, reluctantly). It was also widely used by the Soviets in WW2, and to a lesser extent by the Germans and Americans. Annoyingly, Soviet projectiles often used KE shells to achieve CE-type destruction.lol:



> you seem to have an obsession with setting tanks on fire. At the time this might have been considered a side benefit and not a requirement. Killing the crew and chewing up the equipment was usually considered good enough and if a quantity of very hot metal happened to land in an ammo rack and cause a few rounds to cook off so much the better but few people were going to sacrifice penetration (or much of it) for incendiary effects.



 I've just thought of a silly phrase that can go under my handle (so I dont feel left out), how about 'Tank Arsonist' or 'Panzer Pyromaniac'? Can I use that in my siggy please Shortround? Anyway, back to business: I was talked to by a tank veteran, and watched one on a DVD - both said that they both, in their words "hit it 'till it stops moving" and "made sure you got it", respectively. Admittedly, this doesnt necessarily mean a fire - its just something I'm coming round to. Of course, blowing the gun barrell off would be enough for me. In that Pershing vs Panther G vid though, the first hit sets it on fire, but the Pershing still lets off one or 2 rounds more off for good measure (or just because the crew was tightly-wound?).

In WW2, everyone, excluding the British, sacrificed penetration for incendiary (or rather, blast?) effects. The methods I suggest though, have the best of both worlds.



> Very thinly armored vehicles always presented a problem for for high powered guns. The fuses won't function on the APHE ammo



Thats a good, interesting point. The problem can also be that the projectile just passes right on through - only* creating a few holes, rather than ping-ponging around the interior, as is desirable (saved a Sherman and M10 on at least one occasion). Fuses can also stop penetration against thicker armour. Here is where I might suggest HE.

* = say 'only' because that can still cause damage, just not as much as is desirable, or even usual.

Thanks for the 5.5in info, think I've seen that gun before, but I find heavy arty very hard to tell apart at present.

Wikipedia article on the 5.5in:

BL 5.5 inch Medium Gun - Wikipedia, the free encyclopedia

- which is the one you meant? Mentions nothing of what you said though 8) - perhaps you should update it?

Ah, I do like having arty experts on here! 



> It's true, try any work on Artillery.



Probably a bit muh for me - too outside my knowledge base (for now). Hopefully though, you guys wil rub off on me. 

I would still think though, that most AFVs lost in WW2 were KO'd bt ATGs?



> more later.



Look forward to it, Cheers!


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## Shortround6 (Apr 14, 2010)

schwarzpanzer said:


> Why the seperate generator?


It depends on the power rammers, some were spring driven with spring "cocked" by the recoil of the gun. some used pneumatic rammers and need an air supply from somewhere. others like the American 90mm AA gun and German 105mm AA used powered rollers that move together to grip the round and then spread apart to allow ejection. It is one reason for their high rates of fire.




schwarzpanzer said:


> Thats a good point, but I don't think it would be that much of a difference? - you would have even more confusion IMO having different charges. With single-piece ammo, yellow/green = HE, black = AP, simple? I'm having difficulty explaining myself on this one, but I have thought it through before! Also, to move, say 40 rounds, you would need to make 40 repetitions with single-piece ammo, but 80 with split-load - enough to get RSI?! How much extra does a 128mm projectile weigh though, 60pounds? - OK, I admit thats heavy!



I was thinking more for the towed artillery. 



schwarzpanzer said:


> It depends (as it does to a degree with KE) on the relationship of the size of the gun, and/or efficiency of the CE shell to the thickness, /or quality of the targets armour. Whether 150mm HE shells would cause spalling on an IS-3 though?... (pleease dont tell me this has already been answered?). American armour was very malleable (the best in WW2 apparently), so not so vulnerable to spalling. But, at times the thin armour on the Shermans sponsons was hit by HE shells -which cased the poorly stored ammo to blow. Another point is that Soviet ammo was less stable, and easy to set off with a glancing blow, or HE shell.



Problems with HE shells against armor include fusing, too quick and shell explodes with only the point in contact with the armor and much of the force is dissipated into the air. Too late and the fuse can be crushed and fail to operate properly, or shell body can rupture or shell can ricochet from armor. In the last case even if the shell burst properly if it is even a few feet (or perhaps even inches) away from the tank there will be no spalling from even medium armor. Light armor may be penetrated by shell fragments. For some types of HE to detonate properly the fuse/detonator assembly much set up a shockwave in the explosive in addition to providing a flame or high temperature. A shell that has ruptured or broken on impact may not allow the fuse to set up this shock wave even though it may set the explosive on fire. Given the varying impact velocities depending on range and the normal variations in in mass produced fuses getting optimum results from an HE shell seems to take a bit of luck. 
IIRC the idea of the KV tank was to produce a "shell proof" tank, one that was relativity immune to normal field guns which means 75-76mm HE shells. 




schwarzpanzer said:


> True, but some arty was for frontline use - such as that on the PzIV, Stug StuH. The 150mm I suggested as a desperate measure - as what happened with the LFH18 Flak 88 - both not intended for AT work, but both pressed into service in that role (though by WW2 both of them were expected to fight armour, hence the AP rounds). Soviet arty was also expected right from the start to engage tanks: the 85mm Flak ML-20, for example.



Not really for towed artillery. The idea of providing AP ammo was that these gun batteries would have some means of self defense should things go wrong and enemy tanks turn up where they were not expected. It was much cheaper in men and material to provide 5-10 AP rounds per big gun than to issue, man and provide towing for an anti-tank gun or two to protect each heavy artillery or AA battery. While the PzIV, Stug StuH did provide front line HE support they usually performed a slightly different role than regular artillery. They were equipped with artillery type sights and could fire in the indirect role or map shoot on occasion but even the German army did not have the communications net early in the war that the US and British would later. Having some direct fire weapons available cut down the reaction time to get artillery support from guns located in the rear. 




schwarzpanzer said:


> True, counter-battery fire is bad. The Flak was also vulnerable to the Soviet 76mm US 75mm of their tanks, as it wasnt low-slung like the purose-built PaKs. Also, it is vulnerable to infantry/snipers/grenades etc on the front line. The flak 88 eventually morphed into the PaK 43 though, as would 128 150mms, eventually (though it seems vehicle mounting is the only option for these 2 monsters). These were desperate measures though, I also appreciate that bringing up non-purpose-built, heavy towed arty is difficult.



Not to mention trying to dig the weapons pits to hold them with hand tools, good thing those AA guns had large crews




schwarzpanzer said:


> Not ideal, but better than the 37 and short 75mm (though the latter could use HEAT effectively, and the former could maybe use PPS APFSDS?).


At what point in the war? there was a lot of development in the 4-6 years of WW II. Some of the early Heat shells weren't that good. And trick ammo of the APFSDS isn't going to show up until 1944 at best and then it is doubtful.




schwarzpanzer said:


> That seems wrong to me - are you talking pure penetration performance? Then again, the PaK 38 could fire PzGr 40 APCR (which had serious repurcussions later). Also, it had a higher RoF, could track targets better and had a lower silhouette - as it was designed purposely for this role (but was actually worse all-round IMO).



You are talking about cherries and pumpkins

Penetration at 500meters using standard AP shot for both guns, 90 and 30 degrees, 50mm first. 78mm and 61mm. for the Lf 18 62mm and 56mm.
Same at 1000meters--50mm--61mm and 50mm----Lf 18----62mm and 52mm
pentration of Lf 18 at 1500meters 59mm and 49mm.
MV for Lf 18 using AP shell. 390M/sec. or about 4 seconds time of flight to 1500meters even disregarding wind resistance. Practical range is going to be close to 450meters. 
With a MV of 823M/se the practical range of the 50mm (for getting hits) is going to be around 900meters. THe 50mm does have a much higher rate of fire, double if not a bit more and it weighs about 1/2 what the LF 18 does. 
Niether one can really do the others job. 




schwarzpanzer said:


> Every little helps. The PaK 38 could deal with a T-34 at 1km, but that is too close for comfort (about parity). The LFH18 could destroy, or at least disable a T-34, whilst being immune itself. Also, a hit at <1km would be less likely to be deflected or shattered on the T-34s armour. Unlike the PaK 38 though, it would not be likely to get a 2nd chance if the T-34 missed its shot.



The Pak 38 is going to have trouble at even 1km given the slope on a T-34. The Lfh 18 is going to be in real trouble. The AP shell is about the same as the Pak 38's, a possible kill but no guarantee, it takes until the 3rd or 4th try at a HEAT shell to get 100mm of penetration so heat shells aren't much good in 1941-42. given the low velocity of the 10.5cm round the high arching trajectory may require one or more sighting rounds to get the range. As the range closes the performance of the Pak 38 improves a marked amount. The performance of the 10.5cm does not. 




schwarzpanzer said:


> Thats true. Indirect hits could disable though - allowing for a well-aimed follow-up finishing shot. Also, indirect disabling could, in theory at least, disable several T-34s in a single hit...



Not sure what you mean by an indirect hit? a hit on a tool box or fender? and no, an indirect hit or near miss could not disable several T-34s, not unless they were unlucky enough to have shell fragments hit them directly in gunsight or periscope lenses. Shell fragments from an exploding shell are not going to make it through the armor from several meters away. The shock of the explosion will not cause spalling at that distance nor will it knock out running gear. Bend fenders and break headlights, yes and if you are really lucky it might give the crews a head ache or bloody nose or something.


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## schwarzpanzer (Apr 14, 2010)

Hi tomo,

Now you've gone and added the Czechs, Austro-Hungarians, Poles and French into the mix!  They are not offtopic though, as all nations support seem to be similar? (though to me, ALL support weapons are similar!). This in contrast to ATGs - which are very different beasts.



> If you aim to destroy an AFV with 250mm armor, why would you want to go symmetrical against that? Attack it from air, or aim for tracks/wheels, or make sure to deploy mines if you're on defense, don't hold the line in open field, but in intersected terrain (forest, bocage, towns, by rivers/streams/channels)...
> 
> You can't attack from air, since your enemy has advantage there? Then you have other stuff to worry, rather if super-duper tank is about to appear.



Because you hae no other choice? The IS-3 was not a lumbering beast like the German heavies, remember. Aiming for a mobility kill 1st is a good idea, however, but it may stil need finishing (or just blow the gun barrell off). You can't always rely on ambush? - sometimes head-to-head is the only option?... The IS-3 was apparently also good vs mines, as was also the KV (apart from mobility kills - which could be easily repaired - even then though, it might still be able to limp on?). As you said, air attack was not really an option for Germany in '44/'45 - and you make a good point about air attack also then being a threat, moreso than an IS-3? If you have heavy armour though, both might not kill you? - but will make life unliveable (the thing we've been discussing regarding CE, except from the opposite side).



> While ML-20 is really useful, there is a lot of pieces that dwarf it, some being half as heavy able to move on their own at the battlefield, while firing guided projectiles 30km away...



Ah, yes. I was deliberately stayig away from rockets/missiles though (that would be too much!). I suppose the PzH 2000 is very similar to the vehicles we are proposing? Also, I've seen wheeled 155mm SPGs.



> There is lot to learn about the non-AT arty really



OH NO!! Still, I'm sure you guys can help?



> Then you've should check out their 57mm At gun - the best towed AT gun of WW2, and the best AP performing tank gun 'till Kwk 36 arrived...



The ZiS-2? It was actually unpopular in 1941 early '42 though - not until the Tiger and Stug came on the scene did it gain much poularity - but even then, it had its detractors. The KwK could be considered Dual-Role though, the ZiS-2 not so much. Still, why the 85, 100 even 122mm's AP performance wasnt made to be more like the 57mms totally escapes me.



> Wrong there ("will not work" part) - check out the M1 Abrams cassualties in Iraq in this milenium, Merkava 4 adventures vs. Hezbollah militia.



I suppose HE can disable an Abrams - but has CE directly destroyed one?? The Merkava was blown up by something like a 650kg IED IIRC - impossible to be fired from a field cannon? A Merkava has apparently been destroyed, frontally, by an RPG-29 - which counts, but I mentioned that type of weapon. Any info on those Abrams would be appreciated! 8)



> Chobham IS composed of steel, so methinks you'd need to delete the steel part from that. (I do bang my head for not buying the tank bible last year in Stuttgart, it was both tick cheap)



Yes, but thats only the 'container' (like it is in a HE shell). If you stripped the Chobham off a Challenger, you'd end up with something that resembled a Cheiftain - which is the 2nd, 'steel' layer I mentioned. Deletig the stell on the outer part may allow for more 'shock' on an incoming projectile though?...



> If the spall liner is able to withstand the hit of 20-40kg shell is still not well known for public IMO; I doubt it's THAT effective.



I'm not sure, I just believed that to be the case.  If I happen across any info, I'll have to remember to post it here.



> KV-1 would've indeed put the 85mm/107mm in good use; too bad for Russkies they did that (85mm) in late 1943, in meagre numbers. IS-2 was tested with 100mm (of Naval origin; my favorite Russian gun), but 122 was far easier available.



There was apparantly a KV with IIRC, a 107mm gun - 'The Beast of Leningrad'. Whether it was an actual KV-13 (?) (which was cancelled), or a lash-up, I don't know (or if it was a myth/propaganda). Apparently though, it did see action - so info will be somewhere? However, like the KV-2, it would've had too many limitations. A 107mm on an SU-152 chassis though... The IS-2 also hadan 85mm gun. I like the 100mm much better than the 122mm, though it may be true that the 122mm was more available. I think the 122mm was the main reason that stopped the IS-2 being an effective Heavy or Breakthrough tank.



> E-series? That's "panzer-46" stuff



Well yes, but all the tech, and lessons was available in '43 (even in '42?). Bleedin obvious really, IMO. It did still have those bloody overlapping wheels though!lol: One E-100 was almost completed, and captured by the British (but unfortunately then scrapped). I think that if an E-Seres had to be made, that the Mediums should've got priority - not another Maus clone. even then thoug, the Mediums were stupidly overweight, and apparently not as good as the T-54 IS-3 (though I'm getting to thinking that they were better...).



> But it's suspension layout of transmission were



The 1s part (suspension) is what I said! The transmission was simple, yes, but a bad design apparently (dificult changes poor steering). The early T-34s trans was also poor.


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## schwarzpanzer (Apr 14, 2010)

tomo, sorry, but I've had to split my reply to you. I was 1,000 words over the limit. I managed to shorten it to just under 1,500 words, but it was very kurt txt spk! If this causes problems for the Mods/Admins, just let me know? Thanks.



> Germans might have sticked with their Maybachs (if Russian engine was SO complicated ) and be done with that.



Yep, that is what I suggested. The engine was possible for mass-production (but the Germans couldnt make it in alu). But it had features that were only useful above 6,000rpm - good in an F1 car, not in a tank!  The Maybach was much better, and bizarrely, simpler here (though the Soviet design was copied from an Italian design). Even then though, I'm not too sure if the 'Hemi-head' of the Maybach was all that necessary and desirable. IIRC/IMO a 'Bathtub' head design would be best (but I dont know Diesels that well).



> Those two advantages would've allowe for a more compact vehicle, with better protection for same weight, or less weight for same armor protection.



True. The KV had a poor length-to-width ratio though, whereas the Tiger was almost square. Whether this would be a problem for a German copy though; I dont think so. Having a wider tank would increase the weight though, and a wider tank is necessary both for the length-width ratio and the turret ring diameter for that 88mm gun.



> Again, we build this instead of Panther, not instead of Tiger.



Oh, right. Good point. Bear in mind though, that the top speed would only then be 25mph - the same as the other Panzers, maybe, but not enough to keep pace with a T-34 or Panther. Was top speed was an important, or silly criteria for the Panther design, do you think?



> About the German decision or about advantages of diesel fuel?



Both, sorry.



> The advantages do overweight disadvantages - from late 30's till now.
> If you want so badly the frontal gearbox, than you might take in consideration the engine position too, and move the engine in front, Merkava-style.



It was a German obsession, but I can see both sides to the arguement. It did have advantages when the engine was moved forward though - as in the Geschutzewagen III/IV. A friend of mine had this design in a raccing car - but got a bit peeved when his competitors rammed him - breaking the connector rods, and leaving him unable to at least change gear! So it was a vulnerable design, though I have no sources to its breaking in combat directly available, I do remeber seeing one (in regards to the T-34, probably on Battlefield.ru). Also, changing gear in the T-34 and enturion I know was a knighmare. BTW Electronic Autos, IIRC Hydramatics do not have this problem... The Merkava design is a good one, but it puts the driver in a bad position - with a fore deign, there is a gap creted betweeen the input and output shafts that is just the ideal size for a seated person. Personally, I think the engine put in the centre, with a shorter torque tube and the drive inbetween them would be best - with the turret at the reaar. Torque tube lengths can cause knightmares though, however. As I said though, the Geschutzewagen III/IV seemed to have this feature ( wouldve made a cracking basis for a Katzchen-like APC IMO).



> Both mechanically and by the weight.



Mechanically I have explained above (25mph 'only' - enough?). Weight is a difficult one...(though I will discuss this one elsewhere...).



> The folks from Daimler Benz were influenced by a wrong Russian tank - they've should copied the KV...



The T-34 was a much better design IMO. Sloped armour, lighter and faster. The Panther managed to match the last point, but totally missed the 2nd one and only partly got the 1st. despite all this, it also managed to have thinner armour at the side rear!



> One thing is needed to convert the field gun into AT gun - the will (or order, if you prefer) to do that.



Would it always work though?... BTW the British would not allow their 3.7in guns (Flak 88 euivalent) to be used for AT work - despite the lessons from Rommel. - This even when they had absolute air superiority! 



> You'd need to go to the tank-net.org to find out more - like I did



Drat! Thanks for the source. Can't you just tell me what you learned there?...



> You're forgetting the 17pdr, plus 25pdr for SP arty...



You only said tanks, and I said excluding Lend-Lease. But I suppose you could count the Centurion, Bishop, Achilles, Avenger/Challenger (tanks??) Sentinel? I considered those, but deliberately left them out, as only 4 saw service and were considered SPGs, even though they had turrets - and one was Lend-Lease. Also, the Sentinel wasn't British. I suppose we can count the RAM too?



> I was not reffering to the plethora of guns, but to (your) requirement that Cruisers should have carried almost all of those.



Not all at one time! Not on the same vehicle certainly. I think that at least 4 (or maybe all) would have been in simultaneous service - the 3 3.7in served together, the 2pdr 6pdr did, and the 75mm might have seen service with older variants. I seem to remeber the Matilda II (2pdr) being used in Europe though - so quite possibly! Of course, I would try to have just a few (only 2, if possible?...) and phase the older ones out.



> New thread perhaps?



This was before you added 5 more to the list!  (Czechs, Austrians, Hungarians, Poles and French). I think these will only be touched on here though? - unless you want to create a new Thread for these? May I suggest a title of 'Other Axis WW2 (HE/Support?) Artillery'?

Great post all BTW, as per!8)


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## Shortround6 (Apr 14, 2010)

schwarzpanzer said:


> BTW, I wonder if you might know: were APCBC rounds 1st intended for anti-ship useage?



Yes, and they were developed before WW I. 



schwarzpanzer said:


> That's true, but I wasn't comparing WW2 HEAT to Cold War HEAT. I was just saying that CE (Chemical Energy) Attack is a viable way to destroy tanks - as it was British Doctrine in the Cold War ( is only being fased out now, reluctantly). It was also widely used by the Soviets in WW2, and to a lesser extent by the Germans and Americans. Annoyingly, Soviet projectiles often used KE shells to achieve CE-type destruction.lol:



This may be true but HEAT from rifled guns was a much less viable method in WWII. The poor performance of the HEAT shells meant that it was only used by guns that little, if any, hope of defeating armor by using KE. And if HE worked why did they go to the bother of developing the HEAT shells for these guns?
American 75mm pack howitzer, British 3.7in mountain howitzer, please note the British never fielded a HEAT round for the 25pdr. 
If HE worked the way you seem to think why did the British issue the HEAT ammo in the far east, one would think that a 20lb HE shell would see off the Japanese tanks with their thin armor.



schwarzpanzer said:


> Thats a good, interesting point. The problem can also be that the projectile just passes right on through - only* creating a few holes, rather than ping-ponging around the interior, as is desirable (saved a Sherman and M10 on at least one occasion). Fuses can also stop penetration against thicker armour. Here is where I might suggest HE.



I am afraid the "ping-pong" theory doesn't hold up very well.
1. The Germans certainly didn't intend their AP ammo to ping-pong around the interior. they intended for it to penetrate and then blow up, causing many fragments to fly about in addition to the blast effect. 
2. when penetrating thicker armor the metal that came out of the hole forms secondary projectile/s which fly about the interior at high speed.


on the 5.5in gun, it was in a book by Ian Hogg. it was British doctrine or procedure which may have never been used in combat. Please check the details of the heavy artillery, the 5.5in weighed over 6.5 tons and was not going to be gotten into or out of action quickly or easily and even tracking a moving target with a barrel that heavy could be a chore. 

He has two very good books (actually he has more than I can count)

German Artillery of World War II

and 

British American Artillery of World War II

which cover quote a bit of detail.



schwarzpanzer said:


> I would still think though, that most AFVs lost in WW2 were KO'd bt ATGs?


Artillery was the man killer. if it is forward deployed as AT guns it is not doing it's real job. Just like AA guns. Good, powerful AT guns but if forward deployed they are not tied into the the anti-aircraft net, they are not tied into their anti-aircraft directors and their fuse setters are useless, they are almost use less as AA guns except for firing shells into the sky for morale effect.


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## Shortround6 (Apr 14, 2010)

schwarzpanzer said:


> Would it always work though?... BTW the British would not allow their 3.7in guns (Flak 88 euivalent) to be used for AT work - despite the lessons from Rommel. - This even when they had absolute air superiority



This a common argument but again the reality was a little different. 

some versions of the 3.7 had the trainer and aimer (two men, one for elevation and one for defection) facing backwards. not a problem as an AA gun when the two men used a follow the pointer system to aim/control the gun and never actually looked at the airplane/formation themselves. In other versions they did face forward. The weapon initially had no AT sight, so they would have had to be fitted in forward workshops after suitable telescopes were either shipped out from England or swiped from some other gun and cobbled into place. last the 3.7 was about hallf way in between the 88/56 and the 88/71 and weighed accordingly. 

From Wiki, treat as you see fit;"

"This was mainly because the 3.7-inch (94 mm) gun mobile mounting was almost twice as heavy as the German "88". Redeploying it was a slower operation, and the heavy AEC Matador artillery tractor normally used for towing could operate on hard surfaces only. Additionally, heavy AA Regiments equipped with the 3.7-inch (94 mm) gun were controlled by Corps or Army HQ, or at even higher level HQs, and command of them was not often devolved to the commanders at Divisional levels where the anti-tank role might be required. Prolonged firing at low elevations (not part of the original specification) also strained the mounting and recuperating gear."


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## schwarzpanzer (Apr 14, 2010)

Hi Shortround,

Thanks for the info on the power rammers.



> I was thinking more for the towed artillery.



Though I woudnt know, Idve thought itd be the same for towed arty - maybe even moreso?

Thanks for the detailed info on HE. Though I wouldnt know, I would expect it would be the 1st option. tomo is really the one to ask? The first option would work on thin armour though, like that on the T-26 (also, the 2nd option proably would act like a normal AP round too - only witha bigger hole, also if an unstable shell filled with HE landed in the interior (assuming it didnt exit through the rear) - the crew would be outta there!). All I read was something like 'HE can cause spalling'. 

I remember the A-20 (T-34 prototype) being labelled a 'shell-proof tank', but not the KV (thats not to say youre not right). The KV and T-34 were tested against AP fire from Soviet 76mm guns - a weird way of working, possibly (esp. as they had access to German designs), but one that proved fortuitous.



> Not really for towed artillery. The idea of providing AP ammo was that these gun batteries would have some means of self defense should things go wrong and enemy tanks turn up where they were not expected.



I think the Flak 88 was always ready as a 'Super PaK' after the experience with them in the Spanish Civil War. The Soviet guns also had AT performance included in the design brief. These were always waiting for an excuse to put them in a vehicle, it seems. Of course though, AT work was only a secondary role - but the guns could (and later did) also function that way as a primary role - as often happened with Rommels 88s - much to the Luftwaffes annoyance!

Thanks for pointing out the difference between the PzIV, Stug StuHs roles vs regular arty. I tend to consider them just mobile platforms from them - ignorant, I know. I know they had less elevation though (?).



> even the German army did not have the communications net early in the war that the US and British would later.



Do you have any more info on that? Sounds interesting.

I'm avoiding long-range arty fire. Just using them as an idea of having them as a basis for some super ATGs.

Of course, long-range arty fire could be used against tanks.

There were usages, and planned usages of the 380mm Sturmorser, and that Karlgerat-thingy against tanks, but I dont think we should go into that just yet? There was a funny quote from Rommel, IIRC on the Karlgerat.

Very true on digging weapons pits. Shall we agree that >105mm ATGs are impractical? Then again, the A-19 was OK - maybe the PaK 44 carriage was just badly designed? (it wasn't purpose-built, afterall). It was still OK though, just too heavy ( as you say, hard to dig in). In a bunker though... The flak 88 was still a dangerous opponent late-war, when dug in, it lost most of its vulnerability - also, IIRC, some had their gunshields removed or shortened?



> At what point in the war? there was a lot of development in the 4-6 years of WW II. Some of the early Heat shells weren't that good.



I was thinking untill the 50mm L60 showed up, but even then... Early HEAT shells were the only things carried on German vehicles that could defeat Matildas (exepting those Flaktracks etc). Also, mentioning it, I think that during the Battle of France HE was used to KO a few heavily armoured French/British vehicles?

HEAT was also used later (in desperation though). BTW infighting between the German services led to the crews being held back in the early PzIVs (but not the StuGs, and Michael Wittman started his career here).



> And trick ammo of the APFSDS isn't going to show up until 1944 at best and then it is doubtful.



hartman posted some info on the PPS APFSDS round right at the start of this Thread. Now I dont know, but it was developed for the 37mm PaK 36, so may have been a prototype for the later (?) rounds you seem to be alluding to? (PzGr 44) and thus available early war? (but possibly considered unecessary?). hartmann would be the guy to ask on this one.



> You are talking about cherries and pumpkins
> 
> Penetration at 500meters using standard AP shot for both guns, 90 and 30 degrees, 50mm first. 78mm and 61mm. for the Lf 18 62mm and 56mm.
> Same at 1000meters--50mm--61mm and 50mm----Lf 18----62mm and 52mm
> ...



Yes I know. Thanks for the AP info. 450m? Yep, thats about where it started being effective with AP, IIRC.

At closer ranges, the 105mm will not suffer shatter, but the 50mm will/might(?). BTW did the LFH fire AP, APC, APCBC or APCR rounds? and did they have HE content? - always puzzled me, that one, perhaps now I'll finally find out! The shell I saw though, looked like blunt-nosed APC - so would seem to me to be less likely to bounce off the T-34s armour than the pointed 50mms? No idea if it had HE content or not, but IIRC it didn't - which would make shatter even less likely.

I know hits with HE would be hard past 1km?, but they would cause trouble for a T-34 - unlike with the PaK. Whilst KE is diminished with distance, CE isnt. How able would it be to hit a T-34 (moving @ 32mph) when firing HE, BTW? Even close hits can count.

Funnily enough, the main points when the PzIII got the 50mm L42 were that it could "Outrange the 2pdr, and fire a useful HE shell". Of course, that shouldnt be its raison d'etre - but this gun was mainly used for causing spalling when attacking British vehicles in NA, IIRC.



> The Pak 38 is going to have trouble at even 1km given the slope on a T-34.



True.



> The Lfh 18 is going to be in real trouble. The AP shell is about the same as the Pak 38's, a possible kill but no guarantee,



I was meaning with HE. AP would be in desperation. Though in the early stages of Barbarossa, one was brought up to destroy a problematic T-34 or KV. All t said was "105mm field gun", or something like (not flak though) - so I assumed it mustve meant the LFH18?



> it takes until the 3rd or 4th try at a HEAT shell to get 100mm of penetration so heat shells aren't much good in 1941-42.



Do you mean the 3rd or 4th hit? I know it took about 4 attempts to score a hit with HEAT on early PzIVs (but that got better quickly). In the Battle of France, HEAT shells could destroy a Matilda, so a T-34 even KV shouldnt be too much trouble? They were initially meant for soft targets though IIRC - though AT performance was probably known? (AT rifle grenades of the time used this method).



> given the low velocity of the 10.5cm round the high arching trajectory may require one or more sighting rounds to get the range.



Thats true. I tried it on a simulator, but found it hard (but thats probably more because I'm a crap artilleryman!). I may try again sometime, initially using HE this time...



> As the range closes the performance of the Pak 38 improves a marked amount. The performance of the 10.5cm does not.



True, but the Pak will have troubles with skating and shatter - which the 105mm wouldnt (? - depending on the design of the round). I originally thought Why not have APCR for the LFH18?" but now I can see why that would be pointless (best use it in the Pak 38 - though APCR does load faster... At least I've moved on from the level of ignorance I had then!



> Not sure what you mean by an indirect hit? a hit on a tool box or fender? and no, an indirect hit or near miss could not disable several T-34s, not unless they were unlucky enough to have shell fragments hit them directly in gunsight or periscope lenses. Shell fragments from an exploding shell are not going to make it through the armor from several meters away. The shock of the explosion will not cause spalling at that distance nor will it knock out running gear. Bend fenders and break headlights, yes and if you are really lucky it might give the crews a head ache or bloody nose or something.



I mean a near-miss, sorry - not plunging fire (but I suppose that too...). I meant it could jam or destroy the tracks, though other parts could be hit, like the sights you mentioned (or vent holes etc - which were exposed on the T-34, and often targeted - also on the French Char B btw). 

I know shell fragments wont hurt armour plate otherwise (which is one of the reasons of what tanks were originally designed for).

The shock of the HE shell I went into above, and am not sure, but I expect it would cause spalling? - especially on the T-34, as Soviet armour was very brittle (but apparently less so on early T-34s, I can check). I am pretty sure that a hit on the running gear would disable the tank? Within what range?

Causing the crews problems is one. I remeber hearing stories of equipment falling on crews heads. Also, riveted vehicles were very vulnerable here - the T-34 KV werent riveted, but the T-26 was...

There was also a story of a KV that was hit repeatedly by a flak 88 (though penetration wasnt achieved) but the crew eventually gave up and ran. Some crews would even give up after the 1st hit. A similar tale to that of the KV is one from a British Matilda II - but that managed to retreat. That may not have been destroyed, but it seems as if it also couldnt continue.

Also, imagine the ringing in your ears - be like someone ringing an enormous gong!


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## schwarzpanzer (Apr 14, 2010)

Hi Shortround (again!),

Thanks for the APCBC info. Before WW1??  Why?? 'Ironclads'?



> This may be true but HEAT from rifled guns was a much less viable method in WWII. The poor performance of the HEAT shells meant that it was only used by guns that little, if any, hope of defeating armor by using KE.



True, rifling ruins HEAT performance. I wonder if the PPS round had sliding collars btw? and if it didn't, this would explain its rejection?... I think we'll have to wait till hartmann returns for an answer. Anyway, sliding collars would allow HEAT to work better? I wonder what the changes in HI/B and HI/C were? Were the KwK 37 and Italian 47 75mm guns rifled? Also there was the PaK 97/38:

7.5 cm Pak 97/38 - Wikipedia, the free encyclopedia

- wikipedia only, sorry.



> And if HE worked why did they go to the bother of developing the HEAT shells for these guns?



To set them on fire! They developed HEAT shells for the 150mm SFH18 - but only the 'A' version (as far as I know). The 75mm KwK 37 got developed at least twice more to 'B' 'C' versions. Of course the Germans didnt see the IS-3 coming (which is the only vehicle the 150mm would be needed for (?)).



> American 75mm pack howitzer, British 3.7in mountain howitzer, please note the British never fielded a HEAT round for the 25pdr.



All except the 25pdr had HEAT available? I suspect HEAT would be preferable with a less rifled barrel? IIRC all those also had AP shells available?



> If HE worked the way you seem to think why did the British issue the HEAT ammo in the far east, one would think that a 20lb HE shell would see off the Japanese tanks with their thin armor.



The main problem in Japan was bunkers, which is probably what the HEAT were for. Grant tanks often had to resort to using AP shells to break up Japanese bunkers. Japanese tanks were the only ones vulnerable to the Boyes AT Rifle - PzIs maybe, or the side of others, but even the Sdkfz 251 was resistant.

Japanese tanks would be ideal targets IMO - they had rivets and required padding. Also, in hot environments HE might work better? Would humidity help, or hinder? 



> I am afraid the "ping-pong" theory doesn't hold up very well.
> 1. The Germans certainly didn't intend their AP ammo to ping-pong around the interior. they intended for it to penetrate and then blow up, causing many fragments to fly about in addition to the blast effect.



British AP was intended for this, and seemed to do OK. 
1. True in theory, but often, when you hear of damage to Shermans etc, its when the fuse failed and the round bounced around - decapitating one poor bloke IIRC. When the round detonating upon hitting the armour, this was great news for the crew inside.



> 2. when penetrating thicker armor the metal that came out of the hole forms secondary projectile/s which fly about the interior at high speed.



Very good point - applicable to 'partial penetrations'?.



> on the 5.5in gun, it was in a book by Ian Hogg. it was British doctrine or procedure which may have never been used in combat. Please check the details of the heavy artillery, the 5.5in weighed over 6.5 tons and was not going to be gotten into or out of action quickly or easily and even tracking a moving target with a barrel that heavy could be a chore.





> Thanks, good info again!
> 
> He has two very good books (actually he has more than I can count)
> 
> ...



I have the 1st one, but not the 2nd - heard it wasnt as good. With what you say, the fact that it covers 2 Nations though, I wil have to get it! Thanks!



> Artillery was the man killer.



I dont suppose you have loss rates for both, or the source for that info? If not, I'll believe you anyway! 



> if it is forward deployed as AT guns it is not doing it's real job. Just like AA guns. Good, powerful AT guns but if forward deployed they are not tied into the the anti-aircraft net, they are not tied into their anti-aircraft directors and their fuse setters are useless,



It is argued by some (including me!) that the flak 88 was most useful as an ATG. Why not have fighters ( the Zerstorer concept) for attacking bombers?



> they are almost use less as AA guns except for firing shells into the sky for morale effect.



Do you mean arty, or worn-out AA guns?

I often thought that the Blitz's Morale-booster guns wouldve been better served fighting the Panzers?...


Good points on the 3.7in, and the Wikipedia bit does seem OK to me (heard the thing about elevation from a few other sources IIRC). The 3.7in was used on occasion to fire at tanks though? Succesfully too IIRC? BTW the flak 88 did once fire at Tigers in a friendly fire incident - if it had been PaK 38s, this wouldnt have happened - suppose thats one disadvantage of the flak 88?

BTW The 1st part of that paragraph was me wondering if some field guns were totally unsuitable for AT use? I know the American 90mm AA couldnt use direct fire - but it did eventually morph into a tank killer. Also, the 76mm 3in ATGs were originally AA guns, which were in turn derived from field guns (or whatever!) IIRC.


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## tomo pauk (Apr 15, 2010)

schwarzpanzer said:


> Hi tomo,
> Because you hae no other choice? The IS-3 was not a lumbering beast like the German heavies, remember. Aiming for a mobility kill 1st is a good idea, however, but it may stil need finishing (or just blow the gun barrell off). You can't always rely on ambush? - sometimes head-to-head is the only option?... The IS-3 was apparently also good vs mines, as was also the KV (apart from mobility kills - which could be easily repaired - even then though, it might still be able to limp on?). As you said, air attack was not really an option for Germany in '44/'45 - and you make a good point about air attack also then being a threat, moreso than an IS-3? If you have heavy armour though, both might not kill you? - but will make life unliveable (the thing we've been discussing regarding CE, except from the opposite side).



I'll just say that there is more ways to skin a cat, but if the dog is you real problem, the cat slowly fades away 



> Ah, yes. I was deliberately stayig away from rockets/missiles though (that would be too much!). I suppose the PzH 2000 is very similar to the vehicles we are proposing? Also, I've seen wheeled 155mm SPGs.



Actually, the Pzh-2000 is some 10 times heavier than stuff I've described (made in Singapore); the French Caesar, or Israely, Yougoslavian German wheeled SPHs are really neat IMO.



> OH NO!! Still, I'm sure you guys can help?



Anytime.



> The ZiS-2? It was actually unpopular in 1941 early '42 though - not until the Tiger and Stug came on the scene did it gain much poularity - but even then, it had its detractors.



Not popular by whom?
The top brass didn't like it since it was expensive (yet they put it back into production in 1943 despite that), while it's best AP rounds (APCBC?) pierced Pz-III IV turrets through (both sides!).



> The KwK could be considered Dual-Role though, the ZiS-2 not so much.



The difference is like Tiger's vs. Panther's guns.



> Still, why the 85, 100 even 122mm's AP performance wasnt made to be more like the 57mms totally escapes me.



Yep, I guess they should have produced something better of AP kind.


> I suppose HE can disable an Abrams - but has CE directly destroyed one?? The Merkava was blown up by something like a 650kg IED IIRC - impossible to be fired from a field cannon? A Merkava has apparently been destroyed, frontally, by an RPG-29 - which counts, but I mentioned that type of weapon. Any info on those Abrams would be appreciated! 8)



I'll have to point you to the tank-net.org again for more specific info 



> Yes, but thats only the 'container' (like it is in a HE shell). If you stripped the Chobham off a Challenger, you'd end up with something that resembled a Cheiftain - which is the 2nd, 'steel' layer I mentioned. Deletig the stell on the outer part may allow for more 'shock' on an incoming projectile though?...



I'd venture to say that 'container' has only limited armor value, but more of structural strength.


> There was apparantly a KV with IIRC, a 107mm gun - 'The Beast of Leningrad'. Whether it was an actual KV-13 (?) (which was cancelled), or a lash-up, I don't know (or if it was a myth/propaganda). Apparently though, it did see action - so info will be somewhere? However, like the KV-2, it would've had too many limitations.



Not that many limitations - the turret was more akin in size to KV-85, than of KV-2.



> A 107mm on an SU-152 chassis though...



Nasty surprise in Kursk 
The 122 would've been nice to have back then too.


> The IS-2 also hadan 85mm gun. I like the 100mm much better than the 122mm, though it may be true that the 122mm was more available. I think the 122mm was the main reason that stopped the IS-2 being an effective Heavy or Breakthrough tank.



The IS with 85mm was IS-1, IIRC.
I'm not sure that IS-2 'stoped to be an effective H. or BrTh. Tank' was true for WW2.


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## tomo pauk (Apr 15, 2010)

schwarzpanzer said:


> True. The KV had a poor length-to-width ratio though, whereas the Tiger was almost square. Whether this would be a problem for a German copy though; I dont think so. Having a wider tank would increase the weight though, and a wider tank is necessary both for the length-width ratio and the turret ring diameter for that 88mm gun.



While I may agree that Tiger's L/W ratio was good, KV's wasn't that poor either.
Just how much the turret ring size one needs for 8,8cm??? If the Russkies managed to mount the 85mm, plus a 5th crew member in turret of their T-34s, why the Germans woudl've needed more for their 8,8cm. Atop of that, 85mm was not equipped with muzzle brake, and therefore recoiled a great deal.



> Oh, right. Good point. Bear in mind though, that the top speed would only then be 25mph - the same as the other Panzers, maybe, but not enough to keep pace with a T-34 or Panther. Was top speed was an important, or silly criteria for the Panther design, do you think?



I don't think 25mph would've been too slow; there is no Panthers in our time line, and just perhaps 100 of T-34s beyond 1942 in Wehrmacht anyway 
Since they governed down the original speed of Panther, I'd say it was not worth the trouble.



> Both, sorry.



For German decisions, I'd like to point you to Christian Ankestjerne (www.panzerworld.net); think he was mentioned that in a forum we're the members.
We could have another thread about diesel vs. gasoline, but the price/availability the lower flammability are the main ones.


> It was a German obsession, but I can see both sides to the arguement. It did have advantages when the engine was moved forward though - as in the Geschutzewagen III/IV. A friend of mine had this design in a raccing car - but got a bit peeved when his competitors rammed him - breaking the connector rods, and leaving him unable to at least change gear! So it was a vulnerable design, though I have no sources to its breaking in combat directly available, I do remeber seeing one (in regards to the T-34, probably on Battlefield.ru). Also, changing gear in the T-34 and enturion I know was a knighmare.



The T-34 had problems with type of transmission, not with the layout of same. The clutch operation of 30-ton vehicle was/is not that easy anway.


> BTW Electronic Autos, IIRC Hydramatics do not have this problem...



Exactly. 
(Electric, not electronic...)


> The T-34 was a much better design IMO. Sloped armour, lighter and faster. The Panther managed to match the last point, but totally missed the 2nd one and only partly got the 1st. despite all this, it also managed to have thinner armour at the side rear!



While T-34 featured sloped armor (but not really more sloped vs. KV-1), the horizontal thickness was lower, making 5cmL60 a viable weapon.
You can lump 'lighter' 'faster' together - it was faster since it was lighter. KV-1s, rendered that almost completely, BTW.
OTOH, KV-1 always have had 3rd crew member in the turret, and always featured a radio set. It also featured more modern suspension.

The main T-34's advantage was it's lower price.


> Would it always work though?... BTW the British would not allow their 3.7in guns (Flak 88 euivalent) to be used for AT work - despite the lessons from Rommel. - This even when they had absolute air superiority!



3,7in was not a field gun 
While 8,8cm was widely added to various formations, plus it was there by day one, the 3,7in was more likely to be seen in the UK, rather than in Egypt, main task being protection of Suez Canal locks IIRC - away from front line.
By the time Monty was in hot pursuit (and even before of that), UK army already have had plethora of other artillery more than able to dispose with any Pz-III/IV in direct-fire sights.



> Drat! Thanks for the source. Can't you just tell me what you learned there?...



It all comes to hitting the tank with WP shell, which ignites on impact, engulfs enemy tank with fire... Not very nice.



> You only said tanks, and I said excluding Lend-Lease.



17pdr was mounted in British tank (Challenger)...



> This was before you added 5 more to the list!  (Czechs, Austrians, Hungarians, Poles and French). I think these will only be touched on here though? - unless you want to create a new Thread for these? May I suggest a title of 'Other Axis WW2 (HE/Support?) Artillery'?



Nice title, but it would've to wait till September - my working season started last week, so I have scarce time


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## Shortround6 (Apr 15, 2010)

schwarzpanzer said:


> Thanks for the detailed info on HE. Though I wouldnt know, I would expect it would be the 1st option. tomo is really the one to ask? The first option would work on thin armour though, like that on the T-26 (also, the 2nd option proably would act like a normal AP round too - only witha bigger hole, also if an unstable shell filled with HE landed in the interior (assuming it didnt exit through the rear) - the crew would be outta there!). All I read was something like 'HE can cause spalling '.



with the HE breaking up-rupturing on impact the amount of armor it could penetrate in relation to the size of the shell was rather limited. Naval guns often had several classes of shells from HE to AP, some sort of semi-AP that was rated at a percentage of it's diameter. Full HE wasn't considered useful for piercing any thickness of ship armor (which to be fair, was usually a minimum of 1-2 in.) 'HE can cause spalling' is not the same as WILL cause spalling, you can win at a casino too




schwarzpanzer said:


> Thanks for pointing out the difference between the PzIV, Stug StuHs roles vs regular arty. I tend to consider them just mobile platforms from them - ignorant, I know. I know they had less elevation though (?).



Platforms are more like the Wespe and the various SP 15cm inf gun carriers. They provided mobility way better than a truck but were not meant for direct combat. 




schwarzpanzer said:


> Do you have any more info on that? Sounds interesting.



It is a subject in itself but basically in the beginning of the war a single artilley observer controlled a single battery of artillery or perhaps a 3 battery group. And most often with telephone wire. German use of radio instead was an advance. But one observer could not talk to other batteries and and even artillery battalion Qs could not talk to each other. By the end of the war a Single British observer, should he get permission could call on every gun within range of the target, no matter what unit it really belonged to. Like neighboring divisions, corp artillery, etc. but not necessarily AA units which weren't part of the net although they could be used in planned fire mission. This took many more radios and operators and also miles of wire and operators. 




schwarzpanzer said:


> There were usages, and planned usages of the 380mm Sturmorser, and that Karlgerat-thingy against tanks, but I dont think we should go into that just yet? There was a funny quote from Rommel, IIRC on the Karlgerat.


There was also a case where a Churchill ARVE took out a Tiger tank with it's Petard mortar. Tiger was hiding inside a multi-story building on the ground floor and the Petard bomb collapsed the building on the Tiger. The other ARVEs certainly didn't plan to go Tiger hunting based on that.



schwarzpanzer said:


> I was thinking untill the 50mm L60 showed up, but even then... Early HEAT shells were the only things carried on German vehicles that could defeat Matildas (exepting those Flaktracks etc). Also, mentioning it, I think that during the Battle of France HE was used to KO a few heavily armoured French/British vehicles?



Yes it was, and it worked so well that both sides started a desperate search for something better to use. 
The first 75mm shell for the MK IV was rated at 70mm of penetration. Works better than a 37mm but no guarantee on a Matilda. The Second HEAT shell for the 105 is rated at 80mm penetration. Again how much over penetration is needed for a fair chance of a kill?




schwarzpanzer said:


> hartman posted some info on the PPS APFSDS round right at the start of this Thread. Now I dont know, but it was developed for the 37mm PaK 36, so may have been a prototype for the later (?) rounds you seem to be alluding to? (PzGr 44) and thus available early war? (but possibly considered unecessary?). hartmann would be the guy to ask on this one.


The last numbers in the year usually signify the year of adoption or design, but not always. So PzGr 44 ammo should have been designed or adopted in 1944. Unless somebody has something that says otherwise. 



schwarzpanzer said:


> At closer ranges, the 105mm will not suffer shatter, but the 50mm will/might(?). BTW did the LFH fire AP, APC, APCBC or APCR rounds? and did they have HE content? - always puzzled me, that one, perhaps now I'll finally find out! The shell I saw though, looked like blunt-nosed APC - so would seem to me to be less likely to bounce off the T-34s armour than the pointed 50mms? No idea if it had HE content or not, but IIRC it didn't - which would make shatter even less likely.


It might have been APHE, it wasn't moving fast to worry about shatter and a cap wouldn't have done much good. It didn't generate enough velocity to make APCR worthwhile either. The second AP Design carried 400 grams of HE. You are confusing shattering with shell breakup or rupture. Shatter is when the nose of the projectile hits armor too fast for the steel/alloy to take the stress and nose (point) of the projectile breaks up leaving a blunt rough shape to try to bull it's way through. Shell break up is when the body of the shell can't take the stress of impact and slits open. Given the 1.34kg HE capacity of the standard HE shell I think we can ssume the size of the cavity in the shells was in proportion so the AP shell has a hollow space of about a 1/3 the one in the HE shell. 


schwarzpanzer said:


> I know hits with HE would be hard past 1km?, but they would cause trouble for a T-34 - unlike with the PaK. Whilst KE is diminished with distance, CE isnt. How able would it be to hit a T-34 (moving @ 32mph) when firing HE, BTW? Even close hits can count.


 A tank doing 20mph is moving at 29-30ft a second and the howitzer has a time of flight to 1000meters in excess of 2 1/2 seconds. Tank can move 75 ft while shell is in the air. guess wrong on the speed by 5mph and you miss by about 20ft. guess wrong on range by even 50 meters and you probably miss.


schwarzpanzer said:


> Funnily enough, the main points when the PzIII got the 50mm L42 were that it could "Outrange the 2pdr, and fire a useful HE shell". Of course, that shouldnt be its raison d'etre - but this gun was mainly used for causing spalling when attacking British vehicles in NA, IIRC.



main reason for introducing the 50mm L42 was that it could penetrate at 1000meters what the 37mm could at 100meters and at 500 meters what the 37mm couldn't at any range. At At 1000meters it could out penetrate the 37mm using AP40 at 500meters. I would tend to doubt the spalling story, unless you think that potato masher hand grenades can cause spalling. The 50mm L42 did have a useful HE shell. If it was the same as the 50mm L60 it contained 165gms of HE which might 6 1/2 times what the 37MM HE carried. While not ideal or maybe even what was desired it worked a whole lot better at suppressing dug in British 2pdr anti-tank guns, troops in fox holes/slit trenches or troops in buildings than the 37m HE ammo or just MG fire. 


schwarzpanzer said:


> I was meaning with HE. AP would be in desperation. Though in the early stages of Barbarossa, one was brought up to destroy a problematic T-34 or KV. All t said was "105mm field gun", or something like (not flak though) - so I assumed it mustve meant the LFH18?



HE would have been desperation also. HE will break tracks or damage running gear, blow road wheels off, thus immobilizing tanks.



schwarzpanzer said:


> Do you mean the 3rd or 4th hit? I know it took about 4 attempts to score a hit with HEAT on early PzIVs (but that got better quickly). In the Battle of France, HEAT shells could destroy a Matilda, so a T-34 even KV shouldnt be too much trouble? They were initially meant for soft targets though IIRC - though AT performance was probably known? (AT rifle grenades of the time used this method).



Nope, I mean the 3rd or 4th design of shell. 1st design wasn't very good and few were issued, 2nd design of 10.5cm shell was good for 80mm of penetration according to one source. British were the first to feild a rifle grenade: No. 68 AT Grenade - Wikipedia, the free encyclopedia


More later.


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## schwarzpanzer (Apr 16, 2010)

Hi tomo,



> I'll just say that there is more ways to skin a cat, but if the dog is you real problem, the cat slowly fades away



Took the words right outta my mouth. That IS-3 still needs dealing with though...Air-Defense is another story though? - tanks can't be expected to deal with aircraft?...

Once again, thanks for the help/offers.



> Not popular by whom?
> The top brass didn't like it since it was expensive (yet they put it back into production in 1943 despite that), while it's best AP rounds (APCBC?) pierced Pz-III IV turrets through (both sides!).



It was actually pretty cheap - its carriage was used to reduce the cost of the ZiS-3. Its main 'problem' was that it wasnt so good at firing HE. Piercing turrets through both sides was one of the real problems - while it sounds cool, it is actually less effective. Its 'best' AP rounds were HVAP (debatable) (APCR - BR-271P BR-271N), though APCBC was available (BR-271 BR-271M - dunno if /HE) as was APHE (BR-271K) and AP (BR-271SP). This is why I'm surprised APHE wasnt dropped on the bigger guns - APCBC had much better performance. Then again, apparently the D-10 used Naval ammunition, so that may explain why?

However, once thicker-armoured vehicles came on the scene, overpenetration was no-longer a problem, and production resumed.



> The difference is like Tiger's vs. Panther's guns.



True, though the Panther still fired a reasonable HE shell (75mm being considered the minimum, though IIRC it had a thick casing - thus inferior performance). Thats given me an idea...

Looks like I'll have to go to tanknet? - but I'd feel such a traitor!



> I'd venture to say that 'container' has only limited armor value, but more of structural strength.



Nah, it just holds it in place. Like the skin on a banana.



> Not that many limitations - the turret was more akin in size to KV-85, than of KV-2.



Is that the KV-13? 'The Beast of Leningrad' had a KV-2-alike turret.



> Nasty surprise in Kursk
> The 122 would've been nice to have back then too.



True. The 122 was available - as the A-19 and in the SU-122 - the SU-152 wasnt exactly poor...(maybe even better than the 122mm).



> The IS with 85mm was IS-1, IIRC.
> I'm not sure that IS-2 'stoped to be an effective H. or BrTh. Tank' was true for WW2.



There were 2 IS-1s(or more) and 2 IS-2s (or more). The difference was in armament, a few Soviet sources always say IS-85, IS-100 etc - which is probably the best way to go about things. I say 'more' in brackets, because some IS-2s were 'upgraded' with 122ms ( annoyingly then became IS-2s!). This version is the 1st IS-2, the '44 Model is the 2nd, then I say 'more' because there was then the 'proper' IS-2M. Simple, eh?

The IS-2 was, IMO, not an effective Breakthrough tank because: 1. Its turret front/mantet armour was too thin ( brittle) - making going hull-down futile and 2. Its gun coldnt engage at acceptable ranges, the D-10 would have been far better IMO ( still able to deal with bunkers?). I think the old saying "Stalin turned into Hitler" is true here (but in a bad way).



> While I may agree that Tiger's L/W ratio was good, KV's wasn't that poor either.



It was considered problematic though (albeit > the preceding SMKs).



> Just how much the turret ring size one needs for 8,8cm???



Not all 80+mms are born equal. The KwK 36 may have only had 3mm more in diameter, but had a much bigger shell IIRC. Add to this the much better propellant and you have much more recoil - requiring a larger turret ring - unless you copy the KV-2s 'teapot turret'.



> If the Russkies managed to mount the 85mm, plus a 5th crew member in turret of their T-34s, why the Germans woudl've needed more for their 8,8cm.



In addition to the above, Germans were bigger than Russians though - which always caused problems. Besides, the Tiger was designed with the SS in mind - who had a minimum recruitment height of 6ft. One of the requirements for being a Soviet T-55 tank driver was apparently a height of no more than 5Ft 4in. When Israelis captured T-55s, they didn't like them because they were cramped - despite being otherwise being mostly superior to the Centurions.



> Atop of that, 85mm was not equipped with muzzle brake, and therefore recoiled a great deal.



The muzzle brake was deleted from the L70 gun in the Panther Ausf Fs Schmallturm though...(still trying to work that one out!).



> I don't think 25mph would've been too slow; there is no Panthers in our time line, and just perhaps 100 of T-34s beyond 1942 in Wehrmacht anyway
> Since they governed down the original speed of Panther, I'd say it was not worth the trouble.



There are T-34s though... For what role is the design for? I dont think they gverned the speed of the Panther below 30mph? - and the Jagdpanther could do 32mph IIRC, probably because of the sturdier trans. IIC thogh, it was only engine revs that were governed?

Thanks for the link.
Perhaps another Thread on Gas vs Diesel?



> The T-34 had problems with type of transmission, not with the layout of same. The clutch operation of 30-ton vehicle was/is not that easy anway.



Both, basically, the designs go like this:

Aft: Engine in middle, trans @ rear, driver in front. Trans requires connector links, rods cables that are thin can snap and always require adjusment. Also, they often go through the engine bay, so are subjected to heat stress (especially if they are made of plastic! lol).

Fore: Engine @ rear, trans driver in front. Torque tube connects trans to driver, is basically a thick, solid rod of steel -so no problemos). In addition to this, the torque-tube (basically a surrounding metal pipe) protects it. However it is prone to going out of balance and needs careful manufacture. It also allows storage space in between it the hull sides. It allows the heavy engine to go at the back, helping with cG. The main benefit is, inlike with afts, the gearstick can go straight into the gerabox - giving easy, positive shifts. The gearknob breaking off is probably your main worry here! I think also, that German transmissions were also Clutchless Preselectors? - though transmissions arent my strongpoint.



> Exactly.
> (Electric, not electronic...)



I thought I said Electric? Like I said, not my stongpoint. Were Electric Autos ever used in WW2? Funnily enough, though Hydrmatic is considered the most reiable transmission type now, it wasn't in WW2 tanks (M6 Pershing). Infac, it was the M6s biggest flaw! Also, bizarrely Spur gears were thought to be the Panthers Achilles heel - though I think this is wrong, have been researching it.



> While T-34 featured sloped armor (but not really more sloped vs. KV-1), the horizontal thickness was lower, making 5cmL60 a viable weapon.
> You can lump 'lighter' 'faster' together - it was faster since it was lighter. KV-1s, rendered that almost completely, BTW.
> OTOH, KV-1 always have had 3rd crew member in the turret, and always featured a radio set. It also featured more modern suspension.



The T-34 was a more modern design. Now whilst I dont like it when people equate 'modern' with 'better' in this case, it is true. The armour was much more sloped than the KV ( Panther). 60 degress is the magic angle - any less isnt as much use, 60 degrees should always be aimed for. The T34 still had vertcal lower side armour though - making it vulnerable there. 

The Pz III was much lighter than the Panther, yet much slower...

Thanks for the info. It had torsion bars (according to some sources), yes, but it had differnt roadwheels (which had to be upgraded for the KV-1S IS-2). Still, I think it had its advantages. This warrants further discussion...



> 3,7in was not a field gun



I know. Shouldve put 'AA' in there?



> While 8,8cm was widely added to various formations, plus it was there by day one, the 3,7in was more likely to be seen in the UK, rather than in Egypt, main task being protection of Suez Canal locks IIRC - away from front line.



I think this was not such a smart idea? Still, lots of 3.7ins were available, but werent used. Some were used before this though - proved to be brilliant. I think the 32pdr (well, something like it!) should have come online a lot earlier.



> By the time Monty was in hot pursuit (and even before of that), UK army already have had plethora of other artillery more than able to dispose with any Pz-III/IV in direct-fire sights.



I suppose once the 17pdr came online, it was less use - but the 17pdr wasnt available in massive numbers.



> It all comes to hitting the tank with WP shell, which ignites on impact, engulfs enemy tank with fire... Not very nice.



Like a flamethrower/Molotov? Thought as much (but wanted to be sure). Weird I've never heard of it before. When did it see service?



> 17pdr was mounted in British tank (Challenger)...



The Challenger has always been considered an SPG by my sources (except Wikipedia), but OK, I'll give you that one!



> Nice title, but it would've to wait till September - my working season started last week, so I have scarce time



Thanks. OK. I'm OK till next month (if I'm not in Hospital).


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## Shortround6 (Apr 16, 2010)

schwarzpanzer said:


> True, but the Pak will have troubles with skating and shatter - which the 105mm wouldnt?



Skating?

The second type of AP round for the Pak 38 used a capped projectile which should go a long way in solving the shatter problem. 




schwarzpanzer said:


> I am pretty sure that a hit on the running gear would disable the tank? Within what range?


since blowing parts out of the running gear is with in the capabilities of HE ammunition (given the shell has enough HE content to begin with) the range comes down to at what range can you get an acceptable number of hits? If you have enough ammo to accept 1 immobilized tank for every 20-25 rounds expended then you have a longer range than if you need to immobilize 1 tank for every 8-10 rounds expended. 



schwarzpanzer said:


> Thanks for the APCBC info. Before WW1?? Why?? 'Ironclads'?



they had given up on ironclads by about 1890. In fact compound armor predates that by a few years, compund armor being a thin (ship thin=several inches) steel plate either bolted or "welded" to iron backing plates. The welding being done by pouring molten iron ito the space between the two plates. By 1895 Nickel steel was in use and face hardened "carburized armor was being made in several places by 1900. 
As gun velocity's went from under 2000fps to almost 3000fps the projectile makers had to improve their products. 


schwarzpanzer said:


> Anyway, sliding collars would allow HEAT to work better? I wonder what the changes in HI/B and HI/C were? Were the KwK 37 and Italian 47 75mm guns rifled? Also there was the PaK 97/38:



The Germans were working on sliding collars for HEAT shells but never got them into production despite Hitler ordering 40,000. All the guns mentioned were rifled. It is one reason their HEAT shells did so poorly. See the 8cm PAW 600 for the difference. 140mm of penetration for an 8cm projectile. This by the way is the ONLY smoothbore cannon made in any numbers at all in WW II. Please note that for practical purposes these German HEAT rounds from rifled guns were good for penetration of about their own diameter. The best seems to be the "C" version shell for the KwK 37 which is credited with 100mm or 1.33 times it diameter. American shells didn't do any better 91mm penetration for the 75mm howitzer shell and 102mm for the 105 howitzer HEAT shell. I can't find the figures for the British 3.7 mountain howitzer but it can't have been good. It was noted as being short in length in order to fit into an standard pack mule ammo carrier ans so had a less than optimum stand off distance.
Also please note than many of the guns used less velocity on the HEAT shells than they did on the heavier HE rounds. To high an impact speed degrades HEAT performance, at least in the WW II era. 

on the "ping pong theory" Just what target thickness or range are these projectiles designed for?
If you shoot at the front of an enemy tank and penetrate the frontal armor of the hull the round is going to zip through and hit the engine bulkhead/firewall which is probably not armor but mild steel and just thick enough for structural support and to keep engine compartment fire in the engine compartment. It is not going to take much excess penetrating power for the round to zip right on through and into the engine compartment. Once tanks started using thinner armor on the side than they did the front things get real complicated. Round that goes through front at an angle and bounces of the side (avoiding firewall) is going to have enough power to zip right through both sides. No "ping pong" effect there. If projectile just penetrates enemy tank at 1000yds and "ping pongs"does that mean that the round is failure at 250-500yds where it may have enough power to make it out the other side/rear? 
While projectiles did ping pong around on occasion can anybody find any specifications or design requirements that would suggest that the projectiles were DESIGNED to do it?


schwarzpanzer said:


> It is argued by some (including me!) that the flak 88 was most useful as an ATG. Why not have fighters ( the Zerstorer concept) for attacking bombers?



What happens when the enemy manages to avoid the fighters? or the enemy has better fighters than you do to escort his bombers?


schwarzpanzer said:


> Do you mean arty, or worn-out AA guns?



No, I mean AA guns that are in front line AT positions, disconnected from their fire control equipment or having some of their AA equipment stripped off. An 88 when used as an AA gun was firing with 10-20 seconds of flight time. The target bomber (or formation) flying at 240mph could move a mile or more while the shell was in flight after leaving the barrel. without range and height finding equipment, fire control computers (called predictors) and fuse setters receiving up to the moment data from from the predictor, even a new AA gun was little more than a moral booster for it's own side and perhaps a morale dropper for the enemy. Then you also have the problem that any gun (artillery piece) within a few miles of the front line that fires at anything is going to be "spotted", even by sound, and it's location (even approximate) marked down for counter battery fire.


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## Shortround6 (Apr 16, 2010)

schwarzpanzer said:


> This is why I'm surprised APHE wasnt dropped on the bigger guns - APCBC had much better performance. Then again, apparently the D-10 used Naval ammunition, so that may explain why?



It depends on the size of the burster. A 10-20gram buster isn't going to take up enough volume to make much difference and many APCBC had HE burstes, peaple just didn't want to type the extra letters
In US service sometimes APC was actually APCBC. If there was no actual APC round in that caliber but there were pllain AP and APCBC the BC was dropped. 


schwarzpanzer said:


> However, once thicker-armoured vehicles came on the scene, overpenetration was no-longer a problem, and production resumed.


There were also the problems of factory relocation, ammo production and even perhaps barrel production (that long barrel needed different machinery than the 76.2 barrel) , Russians were heavily into standardizing just a few weapons in the winter of 1941 as long as they worked. By 1943 not only did the Germans have thicker tank armor but Russian production problems had eased up and alternative designs could be considered for production.




schwarzpanzer said:


> True, though the Panther still fired a reasonable HE shell (75mm being considered the minimum, though IIRC it had a thick casing - thus inferior performance). Thats given me an idea...



Some anti-tank guns used a reduced charge for the HE round with lower velocity. This allows for thinner shell walls/more HE and less barrel wear. It does require extra marks in the gun sight and extra training. 



schwarzpanzer said:


> True. The 122 was available - as the A-19 and in the SU-122 - the SU-152 wasnt exactly poor...(maybe even better than the 122mm).


Depends on the job=less armor penetration, less range, less ammo capacity within the confines of an AFV.
More HE and perhaps better penetration of earth and concrete. 



schwarzpanzer said:


> Not all 80+mms are born equal. The KwK 36 may have only had 3mm more in diameter, but had a much bigger shell IIRC. Add to this the much better propellant and you have much more recoil - requiring a larger turret ring - unless you copy the KV-2s 'teapot turret'.



Recoil is proportional to shell weight X velocity + propellent weight X velocity of escaping gas which is usually figured as a constant. 



schwarzpanzer said:


> When Israelis captured T-55s, they didn't like them because they were cramped - despite being otherwise being mostly superior to the Centurions.



Please, more jokes



schwarzpanzer said:


> I think also, that German transmissions were also Clutchless Preselectors? - though transmissions arent my strongpoint.



Early Russian T-34 transmissions had problems, stories of T-34s going into combat with spare transmission tied to engine deck with steel cables and preventing full rotation of the turret. Standard equipment for KV-1 driver was a large hammer to 'assist' in gear shifting. Also stories about KV- drivers just picking one gear and getting tank rolling and sticking with it, not up shifting to hit top speed. 

It was not an easy thing to design a transmission that could handle 500hp in 1939-40 and just like the German tanks, installing it in heavy tanks just adds to the strain. Transmissions were often part of the steering gear, but not so much on Russian tanks.
Russian tanks used what is called "Clutch and Brake". Drive line is laid out like a short "T" with the engine on the vertical part and the drive sprockets on the arms. Engine clutch is between engine and transmission. A right angle gear set changes direction of the drive after the transmission. On each arm there is a steering clutch and a brake. Gentile turns are done by slipping or disengaging the clutch on the inside of the turn. Sharper turns are done by disengaging the clutch and applying the inside brake. While this works OK on light vehicles it becomes increasingly unsatisfactory the heavier a vehicle gets. Long road marches on straight level roads aren't to bad but lots of twists and turns can eat up steering clutches as well as brakes. Going down hill can be a lot of fun too. If the engine isn't pulling (vehicle is 'coasting') de-clutching one track will cause the tank to swing in the opposite direction. Non-syncro transmissions are a bunch of laughs too. If you miss the shift from 3rd to 4th (or vice versa) you often have to bring the vehicle to a complete stop and start over. Missing the shift means you are stuck in neutral. 

Pre-selector transmissions had clutches, think of them as sort of a combination automatic gear box and clutch. Driver used transmission control to select the gear he wanted and when he activated the clutch control the transmission shifted itself. They were more expensive to manufacture and might require more adjustment in the field but they were easier to drive and, with driver less likely to make mistakes, clutches and the gears themselves lasted longer. 

M-5 light tanks and M-24s also used hydromatic transmissions. Again more expensive and in need of more minor maintenance but less likely to suffer catastrophic failure in day to day use.



schwarzpanzer said:


> The Pz III was much lighter than the Panther, yet much slower...



19.5-23 tons/265-300hp compared to 43-45.5 tons and 650-700hp?

Panther had about a 14% power to weight advantage. And an extra gear in the transmission.


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## tomo pauk (Apr 16, 2010)

schwarzpanzer said:


> Hi tomo,
> 
> It was actually pretty cheap - its carriage was used to reduce the cost of the ZiS-3. Its main 'problem' was that it wasnt so good at firing HE. Piercing turrets through both sides was one of the real problems - while it sounds cool, it is actually less effective. Its 'best' AP rounds were HVAP (debatable) (APCR - BR-271P BR-271N), though APCBC was available (BR-271 BR-271M - dunno if /HE) as was APHE (BR-271K) and AP (BR-271SP). This is why I'm surprised APHE wasnt dropped on the bigger guns - APCBC had much better performance. Then again, apparently the D-10 used Naval ammunition, so that may explain why?
> 
> However, once thicker-armoured vehicles came on the scene, overpenetration was no-longer a problem, and production resumed.



The other main shortcoming of 57mm was the increased barrel wear (and it _was_ more expensive - hence only 750 pcs prior the production was stopped) because it fired projectiles at huge speed (for 1941). Since the 76,2mm cannon (the USV model) offered better HE performance, while still very much able to blow the panzers, Russkies decided to drop 57mm and produce the long 45mm (L66), at half price of 57mm.

For 100mm, I'll have to check it before answering.



> Looks like I'll have to go to tanknet? - but I'd feel such a traitor!



I don't have problems reading Serbian forums sites, while my country ( me) was in was with them 15 years ago.


> Is that the KV-13? 'The Beast of Leningrad' had a KV-2-alike turret.



You can take a look at this drawing, with turret almost half of height of KV-2's turret:
KV-1 (107mm gun)



> There were 2 IS-1s(or more) and 2 IS-2s (or more). The difference was in armament, a few Soviet sources always say IS-85, IS-100 etc - which is probably the best way to go about things. I say 'more' in brackets, because some IS-2s were 'upgraded' with 122ms ( annoyingly then became IS-2s!). This version is the 1st IS-2, the '44 Model is the 2nd, then I say 'more' because there was then the 'proper' IS-2M. Simple, eh?



My take would be, production versions:
-one version of IS-1 (85mm)
-two versions of IS-2 (the second version featured glacis plate of constant slope, not cranked)



> The IS-2 was, IMO, not an effective Breakthrough tank because: 1. Its turret front/mantet armour was too thin ( brittle) - making going hull-down futile and 2. Its gun coldnt engage at acceptable ranges, the D-10 would have been far better IMO ( still able to deal with bunkers?). I think the old saying "Stalin turned into Hitler" is true here (but in a bad way).



It was good, but not ideal IMO



> It was considered problematic though (albeit > the preceding SMKs).



That's vague point...



> Not all 80+mms are born equal. The KwK 36 may have only had 3mm more in diameter, but had a much bigger shell IIRC. Add to this the much better propellant and you have much more recoil - requiring a larger turret ring - unless you copy the KV-2s 'teapot turret'.



Quick google search yields this (for HE shells):
8,8cmL56 (Flak): 9,4kg @ 820m/s =6320 kJ (momentum 7710 kgms = recoil force)
85mm M1939 AA: 9,2kg @ 790m/s = 5740 kJ (momentum 7268 kgms)
Hardly that advantageous (under 12 7% respectively), despite all the praise for 8,8. 
With muzzle brake that reduces recoil some 25-30%, 8,8cm KwK should've recoil far less - perhaps the Russkies have done better job converting AA piece to AFV use?



> In addition to the above, Germans were bigger than Russians though - which always caused problems. Besides, the Tiger was designed with the SS in mind - who had a minimum recruitment height of 6ft. One of the requirements for being a Soviet T-55 tank driver was apparently a height of no more than 5Ft 4in.



Hmm, the arrogance tends to backfire...



> When Israelis captured T-55s, they didn't like them because they were cramped - despite being otherwise being mostly superior to the Centurions.



Not superior; perhaps even, and that only until Centurion received 105mm.



> There are T-34s though... For what role is the design for?



Manin battle tank - MBT?



> I dont think they gverned the speed of the Panther below 30mph? - and the Jagdpanther could do 32mph IIRC, probably because of the sturdier trans. IIC thogh, it was only engine revs that were governed?



Shove the Maybach on 'our' KV-88/Panther and you have 30 mph pronto



> Perhaps another Thread on Gas vs Diesel?



Okay 



> Both, basically, the designs go like this:
> 
> Aft: Engine in middle, trans @ rear, driver in front. Trans requires connector links, rods cables that are thin can snap and always require adjusment. Also, they often go through the engine bay, so are subjected to heat stress (especially if they are made of plastic! lol).
> 
> Fore: Engine @ rear, trans driver in front. Torque tube connects trans to driver, is basically a thick, solid rod of steel -so no problemos). In addition to this, the torque-tube (basically a surrounding metal pipe) protects it. However it is prone to going out of balance and needs careful manufacture. It also allows storage space in between it the hull sides. It allows the heavy engine to go at the back, helping with cG. The main benefit is, inlike with afts, the gearstick can go straight into the gerabox - giving easy, positive shifts. The gearknob breaking off is probably your main worry here! I think also, that German transmissions were also Clutchless Preselectors? - though transmissions arent my strongpoint.



That's theory (even if I find some points debatable).
Practice says all-aft layout was better - and it dominated the tank world for some 60-70 years. 



> The T-34 was a more modern design. Now whilst I dont like it when people equate 'modern' with 'better' in this case, it is true. The armour was much more sloped than the KV ( Panther). 60 degress is the magic angle - any less isnt as much use, 60 degrees should always be aimed for. The T34 still had vertcal lower side armour though - making it vulnerable there.



By what accounts it was 'more modern'? The 60 degs are hardly magic, with 30 I'll agree...
You can read the Russian accounts when they've tested Pz-III(E?) and T-34 - Pz-III was faster (almost 70 km/h), with 5 crew members vs. 4 of T-34, better ergonomics radio of Pz-III...
Of course, T-34 have had better gun, much better protection off-road performance.



> The Pz III was much lighter than the Panther, yet much slower...



See above 



> Thanks for the info. It had torsion bars (according to some sources), yes, but it had differnt roadwheels (which had to be upgraded for the KV-1S IS-2). Still, I think it had its advantages. This warrants further discussion..


.

Yep, torsion bars for KV. The road wheels were replaced with ones with bigger radius.



> I think this was not such a smart idea? Still, lots of 3.7ins were available, but werent used. Some were used before this though - proved to be brilliant. I think the 32pdr (well, something like it!) should have come online a lot earlier.



Too bad the Brits haven't found the way to convert pre-war 3in AA piece for AFV use in greater numbers; that one would've lay waste in N. Africa.
OTOH, Commonwealth forces suffered mostly in time Axis forces were equipped with Pz-II Italian tinclads, proving (again) that there is no remedy for bad tactic strategy (save the numeric advantage).



> Like a flamethrower/Molotov? Thought as much (but wanted to be sure). Weird I've never heard of it before. When did it see service?



Think from Normandy on


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## schwarzpanzer (Apr 17, 2010)

Hi Shortround, 

Sorry I have left Emoticons off of my replies to you, please don’t mistake this and think I’m being curt.

This is also the 1st of a 3-part reply.

Thanks for the info on HE again. Thick, malleable armour will make spalling much less likely however – and stop the shockwaves.

I suppose there are 2 types of HE ‘Penetration’?: 

1. The armour is blown apart. Partial penetrations can probably occur here too. Welds can be shredded, as can the actual armour plate itself. 

2. Spalling is caused, crew or equipment are damaged etc.

HE was used against tanks in WW2. I will give the Soviet examples: Early war, HE was the only shell carried by the KV-2 , and was used successfully to destroy Wehrmahcht vehicles (light armour). Apparently too, the T-34 was only available with a few HE shells initially, due to Kuliks meddling – so HE may have been what was used here too? Late War, the IS-2s HE shell was capable of causing spalling on the German tanks thick, but poor quality armour (according to battlefield ru).

HE was used by Tigers to destroy M10s and the sides of earlier ‘Dry’ Shermans – even having advantages here, vs the normal PzGr 39 AP round. American armour was apparently the most malleable of all the WW2 combatants though, so against thick US armour, this often wouldn’t work – only on the brittle armour of the German Soviet tanks, and the riveted/bolted armour of many British ones. However, I suspect HE could still tear the many joins on Composite US tanks apart.

On an aside, HE shells could destroy the thin roofs of tanks – using plunging fire. This is out of my scope though, but it might be nice to cover it here?…

All armour penetrating is a % chance, these figures are not correct, just an example for a 100mm plate @ 1,000m – from 0.1% chance of a 37mm AP round, to a 99.9% chance for an 128mm.

Sometimes, you just have to use what you’ve got available.



> Platforms are more like the Wespe and the various SP 15cm inf gun carriers. They provided mobility way better than a truck but were not meant for direct combat.



Thanks for the info, but I have difficulty understanding these subjects. I did get that though, thanks to your explanation. I think perhaps, that we should start a WW2 Support SPGs thread?…


Thanks for the Arty Observer info.



> There was also a case where a Churchill ARVE took out a Tiger tank with it's Petard mortar. Tiger was hiding inside a multi-story building on the ground floor and the Petard bomb collapsed the building on the Tiger. The other ARVEs certainly didn't plan to go Tiger hunting based on that.



That’s interesting. That’s a different thing though – though I have often wondered what would happen if a ‘Flying Dustbin’ were to hit a Tiger?…

The 1st example I gave was where a large, low-velocity, demolition HE shell, mounted on an SPG has directly destroyed vehicles, due to the blast. The Karlgerat was only discussed though, admittedly – its AT ability, that is.

A torpedo also destroyed a Panzer in WW2. I would guess with HE? Torpex?



> Yes it was, and it worked so well that both sides started a desperate search for something better to use.
> The first 75mm shell for the MK IV was rated at 70mm of penetration. Works better than a 37mm but no guarantee on a Matilda. The Second HEAT shell for the 105 is rated at 80mm penetration. Again how much over penetration is needed for a fair chance of a kill?



Of course, it wasn’t ideal. Why do you say “both sides”? Anyway, one of the measures taken was to develop the HEAT shell! 80mm isn’t exactly great against a Matilda II (78-80mm), but it is better than the 65mm of the 37mm like you said, and even the 69mm of the very rare 50mm KwK 38 L42 - both of those are even at 100m, @ 90 degrees - which is not likely to happen. APCR figures are 79mm for the 37mm (theoretically 1mm over – but in practicality not enough) 115mm for the 50mm L42 – but that is @ 100m 90 degrees. The same source gives 90mm of penetration for the Gr38 ‘/A’ HEAT round though (that’s not much different to yours though). Also, HEAT would comfortably deal with the Matilda I – whereas nothing else could?

Also, even if penetration isn’t achieved, I suspect a series of holes from HEAT rounds would weaken the armour more than 37mm AP shells just bouncing off? 



> The last numbers in the year usually signify the year of adoption or design, but not always. So PzGr 44 ammo should have been designed or adopted in 1944. Unless somebody has something that says otherwise.



I wasn’t talking about PzGr 44, sorry. The round hartmann posted was it’s predecessor, called PPS, IIRC. It is possible that this round was developed in the ‘30s – but not taken further because the PzGr 39 37mm was deemed adequate at that time. When more info comes through from hartmann, then we’ll know more.

PzGr 44 was possibly only issued in 1945, maybe, maybe ’44 - and even then in small numbers and never seeing combat. Even its mere existence is hotly debated and denied by many. Even if it did see service, I don’t really see the use in it (in the guns it was used for), but I think its basic design had advantages for other guns.



> It might have been APHE, it wasn't moving fast to worry about shatter



Good point!



> and a cap wouldn't have done much good.



It would have helped against the sloping armour, and oblique impact angles though. The one I've seen seems more like the 'blunted' type - more suitable for sloped armour.



> It didn't generate enough velocity to make APCR worthwhile either.



But isn’t the whole point of APCR a higher muzzle velocity? - at the expense of a rapid drop in velocity. Whether it could fire a cartridge that would be enough for a decent APCR round is possibly the question?… Thanks for the info though, it’s making me start to see why APCR might not be so hot for this weapon.



> You are confusing shattering with shell breakup or rupture.



No, I’m not. But the two are interlinked? I think pretty much if one happens, then the other likely will too? Except on shot, of course! – even then though, the projectile itself can fragment, rather than just be ‘blunted’. Sorry if I confuse the conversation with linking the two though – I tend to say ‘shatter’ for both. Apparently, another advantage of Uranium projectiles is that they are ‘self-sharpening’.

With both though, penetration can still apparently be achieved – but I wouldn’t bank on it!


Thanks for the info on it being able to hit a moving target (or not). Still, getting even near it with HE might disable it – allowing for a well-timed direct hit? I’m gonna have to dig that Sim out again, and see if I can do it. If I can train myself to do it though (albeit in peacetime) then anyone can?



> main reason for introducing the 50mm L42 was that it could penetrate at 1000meters what the 37mm could at 100meters and at 500 meters what the 37mm couldn't at any range. At At 1000meters it could out penetrate the 37mm using AP40 at 500meters. I would tend to doubt the spalling story,



True, but it would still not be able to defeat Matildas, or do any better than the 37mm vs Cruisers – apart from outranging the 2pdr. This means that it could probably destroy Cruisers at ranges the 37mm couldn’t, true, but couldn’t destroy Matildas, by penetration… I will need more long-range data though IIRC the 37mm’s performance @ normal combat ranges vs Cruisers was not much different?…



> unless you think that potato masher hand grenades can cause spalling.



Funny you should mention that!: There was a device called the Geballte Ladung – which was another desperate measure, intended for destroying tanks. Penetration figures are given as 20mm, but some sources go as far as 60mm! It was apparently intended to fight T-34s though – so the latter figure might not be so silly?…

Thanks for the info on 50mm HE shells, vs 37mm MGs. I would even go so far as to suspect that it was also better than the KwK 37 for direct HE fire against ATGs? – especially mounted as it was on the better performing, more stable, heavily armoured PzIII. How would you rate the PzII here, btw?



> HE would have been desperation also. HE will break tracks or damage running gear, blow road wheels off, thus immobilizing tanks.



I meant that HE rounds had more ‘reach’. AP only being effective to < 500m. Disabling is probably the best you’re gonna get with guns carried on fully-tracked vehicles? (except for spalling). That is excepting even trickier moves with lighter guns - such as shooting up the gun barrel, in radiator grills etc. Of course, such guns as the 37mm can use AP to destroy tracks, but are less effective than 105mm shells for this purpose (though a hit is easier). Then again though, a direct hit with a 105mm shell is probably not needed (?) – a near mss should do it?



> Nope, I mean the 3rd or 4th design of shell. 1st design wasn't very good and few were issued,



The fact that it was developed shows it had usefulness to me.



> 2nd design of 10.5cm shell was good for 80mm of penetration according to one source.



Are you sure that means 105mm, not 75mm?



> British were the first to feild a rifle grenade:



Yes, I remember that. IIRC great penetration, but hard to use? Also, on the subject of Brit infantry AT devices, there was the ‘Sticky Bomb’ – which IIRC used HE to directly destroy armour? Then that Home Guard recoilless rifle-thing (forget the name).


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## schwarzpanzer (Apr 17, 2010)

Hi Shortround (Part 2!),



> Skating?



Yes, bouncing off at oblique angles. 



> The second type of AP round for the Pak 38 used a capped projectile which should go a long way in solving the shatter problem.



Which round is that? Apparently, all Pak 38 AP ammo was capped.

Shatter can still happen when ‘undermatching’ happens. The much larger diameter of the 105mm, combined with its low velocity, would greatly reduce the chance of this happening, when compared to the PaK 38.



> since blowing parts out of the running gear is with in the capabilities of HE ammunition (given the shell has enough HE content to begin with) the range comes down to at what range can you get an acceptable number of hits?



That’s the question. Allsorts of factors to consider (target speed etc). I don’t think ‘hits’ is necessary? – near misses being enough perhaps? The fact that this is so complicated to me leads me to believe it would be impractical, but I’m no arty expert – I wonder what tomo thinks?… To disable a tank may require a whole battery – but an immobilised one can be destroyed by a single LFH 18, IMO. A single gun vs a moving target though?…



> If you have enough ammo to accept 1 immobilized tank for every 20-25 rounds expended then you have a longer range than if you need to immobilize 1 tank for every 8-10 rounds expended.



I don’t get that, but I assume you mean if you have shells to throw away? I would expect that HE shells are cheaper than the specialised alloys, construction and propellants of APs? Also, captured stocks can be used.


Thanks for the Ship armour info. That is Composite Armour though to me (like Chobham). Which is unfair to compare to (most) WW2 tank armour. I expect the iron backing plates were brittle though? – but the join I would expect to negate this?



> As gun velocity's went from under 2000fps to almost 3000fps the projectile makers had to improve their products.



Now that is very relevant. Exactly the velocities encountered here. Still, whilst HE content is necessary (?) – yet at the same time, undesirable, for Naval use, I think it is both undesirable and more to the point, unnecessary, for AT use.


Thanks for the Sliding Collars info. Also, thanks fro reminding me about the PAW. I think though, that the Puppchen did even better?



> Please note that for practical purposes these German HEAT rounds from rifled guns were good for penetration of about their own diameter.



That’s a good one, thanks. This would mean though that a HEAT shell for the FH 18 would easily be able to deal with the T-34 KV? – also, HEAT could have a higher MV than either AP or HE – and thus a longer range, and direct-fire AT ability?

The C shell would probably be enough to deal with any WW2 threat then, saving the IS? (though even then…) Some were actually used after Normandy! (IIRC in penal battalions). By this point though, I would agree that the 75mm L24 was long obsolete (?).

The American British shells were enough, for what they were (not designated ATGs). The 105mm apparently was the best thing at Kasserine pass – being the only thing really capable of destroying Tigers, frontally. The failures of the 3in M1 are less easy to forgive though…

The British pack howitzer would’ve been enough for bunkers? A Boyes AT Rifle would be enough for Japanese tanks otherwise.



> Also please note than many of the guns used less velocity on the HEAT shells than they did on the heavier HE rounds. To high an impact speed degrades HEAT performance, at least in the WW II era.



Doesn’t it also degrade HE performance though? I suppose this destroys my idea of using the LFH 18 for direct-fire – but, many HEAT rounds were used for direct-fire. I think though, that HEAT would only be useful above 500m, so should be ‘charged’ appropriately – leaving anything closer to a ‘super-charged’ APC round. A similar problem was encountered with the D-10T – which used myriad of different rounds for differing ranges (HEAT being for long-range).



> on the "ping pong theory" Just what target thickness or range are these projectiles designed for?



You would need to look at the 2pdr’s design brief (, later, the 6, 17, 32pdr’s) – though IIIRC it was 30mm @ 1,000 yds. I wonder if this was carried on to the 20pdr after? I expect so (never really went away!).



> If you shoot at the front of an enemy tank and penetrate the frontal armor of the hull the round is going to zip through and hit the engine bulkhead/firewall which is probably not armor but mild steel and just thick enough for structural support and to keep engine compartment fire in the engine compartment. It is not going to take much excess penetrating power for the round to zip right on through and into the engine compartment.



That would still be bad. The thing is though, that after penetration, the round would likely ‘tumble’ and not hit @ 90 degrees. It could also hit something other than the firewall. It would behave like a pool ball really. Some German armour actually exploited this ‘tumbling’. Sorry tomo, I know you use ‘tumbling’ to refer to something else (‘skating/bouncing’ in my lingo!).



> Once tanks started using thinner armor on the side than they did the front things get real complicated. Round that goes through front at an angle and bounces of the side (avoiding firewall) is going to have enough power to zip right through both sides. No "ping pong" effect there.



That’s true, but if it isn’t too powerful for the target (like the ZiS-2 vs PzIII, mentioned previously) it will likely be deflected. The probability of this? Well…?



> If projectile just penetrates enemy tank at 1000yds and "ping pongs"does that mean that the round is failure at 250-500yds where it may have enough power to make it out the other side/rear?



1,000 yds is the average combat range. Below that you have allsorts of problems, such as shatter. The best bet is to not let it get that close. If it gets to below 1,000yds, you’re probably dead anyway. The C/BC may slow down the round enough @ close range – also, the caps will have deformed – reducing secondary penetration levels. If it does make it out the other side, or into the rear compartment - then I think it will have destroyed the vehicle! (?)



> While projectiles did ping pong around on occasion can anybody find any specifications or design requirements that would suggest that the projectiles were DESIGNED to do it?



This was the 1st, last method used/intended. The 1st being the WW1 7.92mm ‘K bullet’, the last being Tungsten Rods HESH. Of course, the 1st 2 would also factor in incandescence… German, Soviet APCR would also factor I here – as would the supposed fragments from the AP/HE. Like I wrote above too, all WW2 ( post-war) British AP Shot was intended for this purpose (along with a possible secondary incendiary effect).

When it accidentally happened on AP/HE rounds, this is to me when it was probably most effective. That is, of course excepting the ‘through--through’ incidents that you mentioned (which did happen).



> What happens when the enemy manages to avoid the fighters? or the enemy has better fighters than you do to escort his bombers?



True, though I think there you concentrate on more/better fighters, at the expense of Strategic Bombing. This was Rommels plan, and to me, it makes sense (though his layers of PaKs idea has since been holed, air superiority would bring it back into contention).


Thanks for the AA Fire Control info. 

I suppose using Flaks for AT work would wear out the barrels for AA work. IMO though, using them for AA work would wastefully wear the barrels for AT work. Do you think frontline 88mm AA guns were a waste of time? (excepting for AT work).


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## schwarzpanzer (Apr 17, 2010)

Hi Shortround (Part 3),



> It depends on the size of the burster. A 10-20gram buster isn't going to take up enough volume to make much difference and many APCBC had HE burstes, peaple just didn't want to type the extra letters



True, but I think the 100mm round had too much HE content. I think it’s pointless anyway – if it was only 10-20gms, what would be the point? The British designers came to the same conclusion – it just adds manufacturing costs, time complexity, whilst reducing performance - after-penetration effects are adequate with shot anyway? APHE wasn’t used on British ATGs, except maybe a few initial 2pdr test rounds.



> In US service sometimes APC was actually APCBC. If there was no actual APC round in that caliber but there were pllain AP and APCBC the BC was dropped.



Now that is plain confusing! I have seen some test results from Kubinka on the US 76mm that are ambiguous, but now I’m not so surprised! 

The rounds were named like ‘M79’ etc, and were very confusing anyway. There is a story that goes with them... All types were used in WW2: AP, APC APCBC (all with /HE). I have seen what seemed to be APCBC described as APC – now I know why, thanks! 


Good additional points on the ZiS-2. It actually helped production of the 76.2mm in the short-term though – it’s carriage being more suitable for mass-production ( lighter) found it’s way onto the ZiS-3. The initial 76.2mm had a longer barrel though, which I would have kept (there were 3+ variants).



> Some anti-tank guns used a reduced charge for the HE round with lower velocity. This allows for thinner shell walls/more HE and less barrel wear. It does require extra marks in the gun sight and extra training


.

That’s a good point. I wonder if the KwK 42 had this feature? – and the KwK 40?…

That’s got me thinking – a myriad of different rounds, requires more marks on the sights. For a KT, these might be for: AP, HE, APCR APFSDS - those last 2 being totally pointless? Also, that US 76mm mentioned above. I think the max amount of shell types carried should be 3? (excepting Smoke Canister). I suppose Arty HE fire doesn’t depend on sights so much though? – rather plotting corrections from an observer?



> Depends on the job=less armor penetration, less range, less ammo capacity within the confines of an AFV.



- a lower rate of fire?

I thought the 152mm had more penetration?



> Recoil is proportional to shell weight X velocity + propellent weight X velocity of escaping gas which is usually figured as a constant.



I forgot to add – the KwK 36s cartridge was bottle-necked. I did have figures kicking around till recently on the Brit 17pdr gun vs the US M1A1 – although both are 76.2mm, there is a lot of difference in the levels of propellant.


Hey, that wasn’t a joke!


Thanks for the extra info on the Soviet transmissions. I’ve heard the T-34 story before, but didn’t know it stopped turret rotation.

Yes, the Soviets had much more powerful, heavier tanks, yet their transmissions seemed to lag behind? Transmissions are key to any tank design IMO (or any ither design, for that matter) – I think that should be sorted 1st.

I am just old enough to remember non-synchro, but not why it was bad (missed shifts IIRC, as you said). I think synchro reduces transmission strength though – IIRC Dog-Engagemet is stronger, but harder to use ( in a tank, you want ease of operation – but strength too…).

Thanks for the preselector info. That’s nice and easy. The Hetzer was preselector, so was the Pz38t? Any more? I think that, in this case, more complex German engineering is a good point. How strong is the basic preselector design? Is Synchromesh necessary on it?

Thanks for the info on US Light Tank Hydromatics. They’re the most reliable kind now. I don’t like the M5 Chaffees drivetrain though (the twin engines – not the trans). I heard though, that early Hydromatic fluid was very flammable?



> 19.5-23 tons/265-300hp compared to 43-45.5 tons and 650-700hp?



True, allsorts of things affect top speed. Power being but one of them. Power/weight ratio is not necessarily the thing that affects top speed (but I think we can discount aerodynamics?! lol).



> Panther had about a 14% power to weight advantage. And an extra gear in the transmission.



Ah, but early PzIIIs had 10 gears – 4 more than the Panthers… ( the KT had 1 more, but was also slower). It’s main point was probably the large roadwheels (givin a larger rolling radius) – combined with longer-legged gearing (larger roadwheels up the gearing also).


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## Shortround6 (Apr 17, 2010)

schwarzpanzer said:


> Sorry I have left Emoticons off of my replies to you, please don’t mistake this and think I’m being curt.



No worries



schwarzpanzer said:


> I suppose there are 2 types of HE ‘Penetration’?:
> 
> 1. The armour is blown apart. Partial penetrations can probably occur here too. Welds can be shredded, as can the actual armour plate itself.
> 
> 2. Spalling is caused, crew or equipment are damaged etc.



If you detonate enough explosive close to a vehicle you get an over pressure condition. A blast wave (not shock wave) hits the vehicle. this may be hundreds of pounds per sq in or in extreme cases over a thousand lb/sq in. This can destroy the structure and bend plates. Think hurricane winds or tornado only worse. Or think about houses blown apart by a gas explosion. entire walls blown out on the ground. But think about it. even 5 psi might be enough to destroy the the house if it is applied to the entire wall. 5 psi times 144 sq in per sq ft, times 8 feet high and 12 feet long=69,120lbs of force or just over 34 tons. for a single room wall. 

True spalling is caused by setting up shock waves in the material itself. this requires setting up energy waves (think sound waves, as in a sonic boom) in the material itself. These waves are of such intensity that pieces of metal are thrown off at high speed on the opposite side the force was applied on.

This is what HESH does. High explosive squash head. A special shell (thin walled with a net of some sort to contain the explosive, keep it from splashing out too far) with a base fuse that is designed to detonate the special explosive ( a hard brittle explosive wouldn't work) after it has gone from a column in the shell to a plate sized "patty" smeared onto the armor. a similar amount of explosive, still in cylinder form with one end facing the armor and detonating even a fraction of an inch away is hardly going to have the same effect.
If you use a big enough shell and detonate it close enough you may get spalling effect. True the thickness and quality of the armor will have some effect but how thick was the armor of the T-34 prototype that was supposed to "shell proof" against 75-77mm shells?



schwarzpanzer said:


> The 1st example I gave was where a large, low-velocity, demolition HE shell, mounted on an SPG has directly destroyed vehicles, due to the blast. The Karlgerat was only discussed though, admittedly – its AT ability, that is.



I am sure that by searching hard enough you can come up with freak happenings for a lot of weapons. Most of the discussions may be post war by war gamers of the "Timmy, the power gamer" type. I am not sure you could even fire Karl-Gerat at zero degrees elevation. Loading rates, traverse, and low velocity mean these would be short range, limited, one shot wonders at best. And just when does the rocket on the 380mm Stormtiger kick in? after it has left the muzzle? does wonders for accuracy. doesn't matter against large building or group of trucks or at 200-300 yds but for a long range weapon? 




schwarzpanzer said:


> Of course, it wasn’t ideal. Why do you say “both sides”? )........ Also, HEAT would comfortably deal with the Matilda I – whereas nothing else could?



I say both sides because both the Germans/Italians/ Japanese? and the Allies were looking at HEAT or shaped charges from before the start of the war. Pretty much means nobody was happy with HE against tanks.

You might want to check on that "comfortably deal with" also. There seemed to be more variation in round to round performance of shaped charge shells than KE projectiles. And you have to figure the angle of impact. for instance a HEAT shell impacting a 60 mm plate at 45 degrees actually has to make a hole through 84.4 mm of material, it doesn't magically align itself for a 90 degree penetration. It doesn't have the skid or ricochet problem that KE projectiles do though 


schwarzpanzer said:


> The round hartmann posted was it’s predecessor, called PPS, IIRC. It is possible that this round was developed in the ‘30s –


There was a bit of work going on about super long range shells for artillery or for getting an AA shell to altitude quicker. But that was to get an HE payload to the target, not a KE projectile which might present some different problems even if you do have the shape right. 


schwarzpanzer said:


> But isn’t the whole point of APCR a higher muzzle velocity? - at the expense of a rapid drop in velocity. Whether it could fire a cartridge that would be enough for a decent APCR round is possibly the question?… Thanks for the info though, it’s making me start to see why APCR might not be so hot for this weapon.



The AT and Tank guns that used APDS got about a 30-40% increase in penetration and had to pay the price of Tungsten carbide use for that. Maybe you can fire a standard 75mm APCBC projectile out of a 105 barrel by using sabots but is it going to be any faster/better than a normal 75mm AT gun? And you have the bigger size/weight of the 105. 




schwarzpanzer said:


> No, I’m not. But the two are interlinked? .



I think you are.
Armor penetration depends on a lot of factors and the actual mechanics/process changes with the metallurgy and impact speeds ( and who you listen to). 
Going back to the iron clads it was found that a hard plate could cause a cast Iron ball/shot to shatter on impact. Chilling the cast shot as it cooled made it harder and better able to penetrate and the hardness race was on, except that too hard meant brittle and the plates could crack right across or the shot broke up. for englongated projectiles they tried chilling just the nose or using a difeerent heat treat on the nose than on the body so the body would remain a bit softer but tougher (bend a bit before breaking). It was found that a bit of point worked better than a flat nose (or ball shaped nose). It stressed a local point on the armor and weakened it and tended to push material aside rather than trying to shear out a plug like a high speed flat faced punch. At higher impact speeds some of the dynamics change. But maintaining the point was found to be critical to best performance. At certain speeds (around 2000fps ?) it was found that the heat treated points of the projectiles began to shatter on impact and minor changes to heat treatment and/or alloys didn't solve the problem. This is the start of the "piercing cap" a cap of a softer but tougher material was placed on the front. on impact it spread the load to the shoulders of the projectile and protected the nose. As it deformed it pre-stressed the armor target and even acted a bit like a lubricant as the intact hard nose of the projectile went through it's own cap penetrated the armor plate. 
An HE shell body breaking up under the stress of impact and spilling it's load isn't really the same thing. 


schwarzpanzer said:


> Funny you should mention that!: There was a device called the Geballte Ladung – which was another desperate measure, intended for destroying tanks. Penetration figures are given as 20mm, but some sources go as far as 60mm! It was apparently intended to fight T-34s though – so the latter figure might not be so silly?…



that device has 42 oz of TNT or explosive in it. or almost 1.2 kg. How much in a 105 shell? 
Some accounts speak of trying to throw/place the charge on the engine deck/grates which are hardly 60mm thick. 





schwarzpanzer said:


> Then again though, a direct hit with a 105mm shell is probably not needed (?) – a near mss should do it?


a mighty near miss. I think a 150-155 had to land under 10 yds away to have reasonable chance of disabling a tank and the 105s carried 25-33% of the explosive of a 150-155mm?


schwarzpanzer said:


> The fact that it was developed shows it had usefulness to me.


Well, you have to start somewhere and a look at the drawings shows why it wasn't very good. In 1938-1940 a lot of people knew the general principal which dated back to before 1900. It was turning this laboratory trick into a usable weapon that took a few years. The fact it wasn't issued in numbers and that the version which replaced it was only marginally better than the AP shot indicates the first version wasn't very good.




schwarzpanzer said:


> Are you sure that means 105mm, not 75mm?


Not according to one source. 




schwarzpanzer said:


> Yes, I remember that. IIRC great penetration, but hard to use?.



Lousy penetration. about 2 in or 50mm and you needed a 90 degree impact angle to get that. Once you got through the 30mm armor of a MK III or IV with an angled impact did it really have much more effect inside the tank than an anti-tank rifle bullet


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## Shortround6 (Apr 18, 2010)

schwarzpanzer said:


> (Part 2!),
> Which round is that? Apparently, all Pak 38 AP ammo was capped.
> 
> Shatter can still happen when ‘undermatching’ happens. The much larger diameter of the 105mm, combined with its low velocity, would greatly reduce the chance of this happening, when compared to the PaK 38.



Early Pak 38 AP was not capped. Shatter has little to do with shell diameter or size and a lot to do with impact velocity. It also has little to do with undermatching. If you have a big enough overmatch then you get penetration anyway in spite of shatter. 




schwarzpanzer said:


> I don’t get that, but I assume you mean if you have shells to throw away? I would expect that HE shells are cheaper than the specialised alloys, construction and propellants of APs? Also, captured stocks can be used.


 At long range the dispersion is greater and more shells are going to be needed to get hits. The longer the range the more shells needed per hit. so how many shells per hit or tank knocked out is acceptable? also consider that for towed AT or open topped vehicles the longer the engagement goes on the greater the likelihood of the enemy artillery joining in. Depends on your HE shells, high explosives may be in shorter supply than steel, fuses aren't cheap and good HE shells require high quality steel. Mediocre ones don't.



schwarzpanzer said:


> Thanks for the Ship armour info. That is Composite Armour though to me (like Chobham). Which is unfair to compare to (most) WW2 tank armour. I expect the iron backing plates were brittle though? – but the join I would expect to negate this?


The steel was the hard brittle part, think of snapping old sword blades, the iron was rolled or wrought iron, not cast iron. Talk to a plumber who has beat on a malleable iron fitting try to crack it by mistake



schwarzpanzer said:


> Thanks for the Sliding Collars info. Also, thanks fro reminding me about the PAW. I think though, that the Puppchen did even better?



I am not sure but at the time it was considered that spinning the projectile (rifling) cut the ability of a given shaped charge design in half. 




schwarzpanzer said:


> That’s a good one, thanks. This would mean though that a HEAT shell for the FH 18 would easily be able to deal with the T-34 KV? – also, HEAT could have a higher MV than either AP or HE – and thus a longer range, and direct-fire AT ability?



A source gives the HEAT penetration of the 15cm howitzer shell as 160mm so it should have the ability. But in WW II there was a fusing problem and HEAT shells wouldn't function properly at high impact velocities. In some cases the heat shells were fired at less than full charge even by howitzers. So you have the ability to penetrate IF you hit but a lower chance to hit at ranges over 500meters and the chances get worse the longer the range. 



schwarzpanzer said:


> The British pack howitzer would’ve been enough for bunkers? A Boyes AT Rifle would be enough for Japanese tanks otherwise.


The projectile was requested by the Indian Army and pretty much used only by them. Depending on the Boyes would have put the Commonwealth forces at a major disadvantage. Not only were some later Japanese tanks more heavily armored (Type 97) but single penetrations of vehicles by even 12.7-14.5mm bullets doesn't lead to destruction in most cases.



schwarzpanzer said:


> Doesn’t it also degrade HE performance though?
> 
> 
> > Why should it? unless you are trying to shove HE shells through thick armor.
> ...


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## Shortround6 (Apr 18, 2010)

schwarzpanzer said:


> (Part 3).
> Arty HE fire doesn’t depend on sights so much though? – rather plotting corrections from an observer?






schwarzpanzer said:


> - a lower rate of fire?
> 
> I thought the 152mm had more penetration?



loading 40-50kg projectiles vs 25kg projectiles? book figures for towed howitzers list same rate of fire 3-4 per minute but that is with a large gun crew. 

See:

http://en.wikipedia.org/wiki/152_mm_howitzer-gun_M1937_(ML-20)

http://en.wikipedia.org/wiki/122_mm_gun_M1931/37_(A-19)

Please note the 152mm HEAT shell was post war. 






schwarzpanzer said:


> Hey, that wasn’t a joke!



Yes it was, but this needs a thread of it's own.




schwarzpanzer said:


> I think synchro reduces transmission strength though



It depends on original design. If you are trying to fit synchros into an existing gear case you have to make the gears thinner and less strong. If you are designing from scratch and transmission case size is unrestricted there shouldn't be much problem.



schwarzpanzer said:


> Ah, but early PzIIIs had 10 gears – 4 more than the Panthers… ( the KT had 1 more, but was also slower). It’s main point was probably the large roadwheels (givin a larger rolling radius) – combined with longer-legged gearing (larger roadwheels up the gearing also).



With low rpm engines you have less over lap of gears. I drive a 34 ton fire truck with a 450hp engine and a 4 speed automatic. While much faster than a tank I think the same principles appliy. Max engine speed is 2200rpm. While it will do 55mph on the level it often is down to 30mph on hill, max rpm in second gear, 1st is good for 15mph. if it shifts to 3rd gear on the hill it is below it's torque and power peaks and can't rev up. More gears mean more options and better mobility in less than flat smooth conditions. 

Other things that can affect tank speed are the rolling resistance of the track itself, some designs had twice the rolling resistance of others and track tension. slack track having less rolling resistance. But each of these choices have there down sides too


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## hartmann (Apr 23, 2010)

Hi to all ¡

two parts post 



> Necking-up is connected to frontal part of a cartridge, not the aft part. Brits have necked-up 57mm to 75mm, but size of breech remained the same; Russkies have necked-up 12,7mm to 20mm, and 14,5mm to 23mm (don't confuse that one with VYa-23 ammo). They all have doubled/tripled shell (projectile) weights, at cost of 1/4 of muzzle velocity.
> Sorry, when you said necked-up, I thought you meant necked-down (bottle-necked, Maroschek). I've never heard of what you are talking of before - love new info! So, an oversized projectile was put on a standard cartridge? I've heard about this being done with HEAT warheads on PaK 36s 38s, but never anything else -thanks!



The MG 151 was necked up to 20 mm from the original 15 mm. It was relatively common practice. Both captured Soviet Flak guns, the 76, 2 mm and the 85 mm were necked up to accommodate the standard HE and APCBC-HE shells from the Flak 36 88 mm gun when all the original Soviet ammo was depleted. 




> I would consider it to be 'prototype PzGr44'?



Probably it was a sort of prototypic PzGr 44. I don’t know for sure (as I said previously, there is very little available data).




> Is that what happens in deflected shots/shells?




Oh, no ¡ My English… Sorry .
I will explain it:

-	Tumbling = the shell/shot is travelling in the air, and starts to yaw.
-	Ricocheting = the shell/shot is deflected downwards/upwards when impacts in a plate target.




> When you say SVAP - do you mean Super Velocity Armour-Piercing - APDS?



Yes, although I also include APCR and APNCR.



> I think some APFSDS spin?




Yes, but It is not worth enough when We like the best results for pure penetration and shot integrity.

The rifling of the gun imparts spin to the APFSDS shot, which also translates in inertial gyroscopic momentum. This means that some energy is lost in heat formation during the contact of the rifling with the sabot by friction, and also, it supposes a high stress to the shot itself. 
The rifling in a gun limits the length-to-calibre ratio of an APFSDS shot to some 7 or 10-to-1, when the state of the art APFSDS-T shots fired from smooth-bored guns have a ratio as high as 17 or 20-to-1.




> It all depends on the manufacture quality and material used (the APDS manufactured by UK in the WWII were very brittle because inadequate sinterised technology, in contrast to Germany).
> What?! The tungsten??




Really, what they use is tungsten carbide alloys (less denser than pure tungsten, and also more brittle if they haven’t a good malleable matrix composed of other heavy metals). Putting it simply, the tungsten carbide is made as powder, which binds with other compounds as a “glue”.
Quite tricky job 




> All have pyrophoric effects when they are finely powdered and oxidized.
> Would this automatically happen upon penetration?



Yes, It happens automatically when the shot impacts against the plate. The nose is “destroyed” or break and the powder generated, when contacts with ambient moisture, oxidizes and make the pyrophoric effect or flame shown.



> You can check in Jentz books some data and drawings concerning this proposal.
> Actually, you've jogged my memory. It was intended for the E-75? Which Jentz book please?



The book is “Volume 2 - VK45.02 to Tiger II: ISBN: 0764302248”. But he Schiffer editing, not the Osprey (shortened edition)

BTW, the E-75 also had to carry this 105 mm gun.




> I heard tungsten was much denser than steel? –




You are correct. The pure tungsten has a density of 19,25 g/cm3 versus the steel which has a density of 7,850 g/cm3 (by comparison the water has only a density of 1 g/cm3). 
But…. You have to take in account that the APCR (PzGr 40), and APDS were made from Tungsten carbide, which is something like 14,95 g/cm3. Pure uranium is far denser than steel or tungsten carbide, reaching 19,07 g/cm3 of density.




> wonder how the barrel was on the flak version? - how many pieces?...



As far as I know, all the Flak 41 guns had a two pieces barrel.




> I wonder if performance would be improved with the standard propellant charge?



Yes, It probably would obtain some 10 to 20 m/s more (maybe even more), but not enough to justify such increase in barrel length without more propellant.



> Also, on that point, I wonder what length the barrel should be to burn the propellant entirely




That is very difficult to answer. 
It depends on the quality of propellant, quality of obturation, time of burning, maximum admissible chamber pressure among much other parameters (that is inner ballistics, which I am only starting to grasp in).
Actually It is been studied how to burn all the propellant by plasma ignition and so on, but It was not available in 1940s-1950s (even now It is completely experimental).
The fastest answer is: the longer the barrel, the more efficient is the use of the propellant (but also It carries penalties).




> I have some scarce data for the 128 mm L66 gun at some 1080 m/s with the PzGr43 versus plates of 80-90 Kg/mm2 strength was punching trough something like 270-276 mm at 30º. With the standard 128 mm L55 gun, it consistently punched through 248 mm at 30º with 950 m/s.
> Also I have some data with plates placed at 45º.
> Great info - that should do it! (Assuming the IS-3 never had 280mm). Are those angles from vertical? –



They are from the vertical.




> So there’s 3 different BC designs?: PzGr 39, PzGr 39/43 PzGr 39/43 (2nd design) - ?




The design for the piercing cap and ogive was pretty standard from 1937 to 1943 (the designations of PzGr, or PzGr39), (being very blunt compared to almost all nations) but in 1943 the crh of the ogive was changed, among the form of the piercing cap (hence the new designation PzGr 43), making both them even more blunt to cope with extreme oblique plates.
Those changes, among the differences between big and little cavity of shell, were given different designations.




> I was kinda hoping it was a scan from a book. I was wanting to show it to an associate (I wont unless you give me permission).



I think that it was from a manual or BIOS/CIOS document written after the war. You can show the design as It has been already shown in another forum by other people (the photograph is what is not shown by the moment).


Hope this helps


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## hartmann (Apr 23, 2010)

Second part of post



> If that photo is a good one, it may show a Ballistic Cap? (Or not). If it's the PPS in that drawing though, then it probably wont (?)



I have been seeing the photo and (excluding the rust which it has in some zones ), it hasn’t cap.



> It was trialled at captured French Russian carriages, so perhaps they were intending to use it as a towed piece?



Initially, it was intended to be a field gun, but the ballistic qualities were so good that It was changed to AT gun. 
The preliminary trials showed that it was too cumbersome, so it was modified to a self propelled AT gun (multipurpose) and adopted in the Jagdtiger and Maus-E-100.




> It was trialed at captured French Russian carriages, so perhaps they were intending to use it as a towed piece?
> That’s the 2nd time my memories been jogged - yes, I remember! What was its intended role there? DP, HE or AT? What was it called? - PaK 44? - if so, that just screams ATG.




Initially It was just called as 12,8 cm K44 (dual purpose) as Tomo said.




> IS the 220-228mm if armour the real thickness or effective thickness.



The 220 mm are real thickness, but only at the flanks of the turret.




> Thanks for the APCBC info. Before WW1?? Why?? 'Ironclads'?



The firsts APCBC shells were introduced more or less in 1894.



> wonder if the PPS round had sliding collars btw?




I think that it had nothing like sliding collars (probably they smoothed the barrel partially, I’m guessing). 
The rings were the petals of the sabot, which broke and separated when the shot reached the muzzle (you can guess where the Soviet design of ring petals did origin almost certainly).
Taking in account that in late 1944 and early 1945 the design of the German petals was more similar to the current guns, I would guess that this PPS was from early 1944.





> Were the KwK 37 and Italian 47 75mm guns rifled



Yes, they were all rifled guns.



> I am afraid the "ping-pong" theory doesn't hold up very well.
> 1. The Germans certainly didn't intend their AP ammo to ping-pong around the interior. they intended for it to penetrate and then blow up, causing many fragments to fly about in addition to the blast effect.
> British AP was intended for this, and seemed to do OK.




The British decision to go for the AP shots without explosive cavity, was more related to the inability to make a fuse which functioned properly more than to be intended for this. The British navy specified APCBC-HE shells with a very big HE cavity.




> 2. when penetrating thicker armor the metal that came out of the hole forms secondary projectile/s which fly about the interior at high speed.
> Very good point - applicable to 'partial penetrations'?.




Yes, the can form plugs or discs which are ejected at the interior, at a very similar velocity to the shell when impacts.




> The last numbers in the year usually signify the year of adoption or design, but not always.



Quite correct Shortround.




> Originally Posted by schwarzpanzer
> At closer ranges, the 105mm will not suffer shatter, but the 50mm will/might(?). BTW did the LFH fire AP, APC, APCBC or APCR rounds? and did they have HE content? - always puzzled me, that one, perhaps now I'll finally find out! The shell I saw though, looked like blunt-nosed APC - so would seem to me to be less likely to bounce off the T-34s armour than the pointed 50mms? No idea if it had HE content or not, but IIRC it didn't - which would make shatter even less likely.
> It might have been APHE,




Yes, Initially It carried a plain AP-HE shell. 
Sometime after, they used APCBC-HE shells, although not in the way that is conventional, and in very limited use. 
The main way to defeat tanks with the 105 mm howitzer was with HEAT (“Hohlladung”) rounds.




> AP (BR-271SP).



This was an APBC solid shot (SP means “Sploschnoyi” or “Solid”).




> This is why I'm surprised APHE wasn’t dropped on the bigger guns - APCBC had much better performance.



The main reason was that manufacture high performance APCBC-HE shells was far more complex and technology demanding than simple monoblock AP-HE shells.




> Then again, apparently the D-10 used Naval ammunition, so that may explain why?




Concerning HE ammo, It was true, because the D-10 gun was directly derived from an antiaircraft gun, but when they used It as AT gun, they lacked this kind of AP ammo and had to design it from zero point (and had to use the same design that was used in previous guns).




> True. The 122 was available - as the A-19 and in the SU-122.



The D-25 gun was derived from the A-19 field gun, but the 122mm gun carried in the SU-122 was a howitzer, the M-30. The M-30 never carried AP-HE shells as far ass I know, only HE and HE-frag (although they obtained some HEAT shells late in the war).





> all Pak 38 AP ammo was capped.



The first PaK 38 PzGr shell was uncapped. The PzGr 39 was an APC-He shell, and the last series, the PzGr 39/42 was an APCBC-HE shell, almost only issued to the 5 cm Flak 41.

Hope this helps


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## schwarzpanzer (Apr 24, 2010)

Hi Shortround,

Thanks for the HE info. In a tank, HE is used for 2 different things: 

1. Attacking targets out in the open - such as ATGs, infantry etc. This often means not a direct hit, often relies on frag blast effect. I expect this could disable tank tracks? (if very close - which is possible on a tank @ long range, as are even direct hits).

2. Attacking buildings and bunkers etc. Now this is where I fall down. As I see it though, the explosive detonates on contact and rips the target apart - I would expect the same to happen to metal plates, if they were brittle or thin enough, or badly joined. I know about HESH, but I would expect HE to work slightly similar? (only with less velocity on the 'scab').

BTW, apparently Soviet HE shells were very simple and effective - having a 2-positon 'switch' - one for blast (number 1., above) and one for contact (2.).



> If you use a big enough shell and detonate it close enough you may get spalling effect.



Thats what I'm pretty much meaning. It depends a lot on the exact shell (size quality) vs the exact armour (thickness, quality cconstruction) though. I'm only talking of direct hits (unless for track jamming).



> True the thickness and quality of the armor will have some effect but how thick was the armor of the T-34 prototype that was supposed to "shell proof" against 75-77mm shells?



45mm sloped @ 60 degrees. Aprox 60-70mm @ round IIRC (turret front). Turret sides rear were somewhere inbetween (all aprox equal). 'Shell-proof' was actually referring to 76.2mm Soviet AP shells - not just artillery fragments (which the pre - shell-proof BT could keep out). T-34 prototypes were good quality though, but unreliable - the exact opposite of production versions!



> I am sure that by searching hard enough you can come up with freak happenings for a lot of weapons. Most of the discussions may be post war by war gamers of the "Timmy, the power gamer" type. I am not sure you could even fire Karl-Gerat at zero degrees elevation. Loading rates, traverse, and low velocity mean these would be short range, limited, one shot wonders at best. And just when does the rocket on the 380mm Stormtiger kick in? after it has left the muzzle? does wonders for accuracy. doesn't matter against large building or group of trucks or at 200-300 yds but for a long range weapon?



lol. The Sturmtiger thing actually happened - apparently 12 Shermans were destroyed in a single hit IIRC. Of course though, this was, as you say, a freak happening. Probably in desperation, or set up with the help of an observer, pure luck, skill or pure accident - but I used it to hopefully illustrate that a smaller, higher velocity weapon, such as a SiG-33 could easily destroy a single Sherman with a direct hit?

I'm not sure Zero Elevation was what was suggested? - but then, it was Krupp, so who knows?

Rommel made the same point you did, to Hitler, because of what Krupp said. Probably Krupp was a gigantomaniac loon, but then again?... I think it wasnt so much Hitler that was the loon, but his designers (Henschel, Porsche, MAN Krupp all seemed to have produced no end of idiotic ideas).


Of course HE isnt ideal for Anti-tank use, but if its all thats available... I'm trying to find out just how useful that was. BTW the 1st tanks to be destroyed (in WW1) were very likely destroyed by HE shells.

I was thinking that, as the KwK 37 had a high trajectory, that the shells would not hit it flat-on. I wondered whether I shouldve put 'comfortably' but IIRC it was the best option. There was also the turret to consider. The Matilda was a small target though (but slow) and the KwK 37 hard to get hits with - especially early war, as training with this round had been sabotaged by infighting. It did score hits on the fast-moving, low-slung T-34 though (some of them by Michael Wittman). Once it hit though, the cramped confines of the Matilda would have made the effets devastating. True that variations in rounds would also have hindered though - but was it really that bad?

I have heard of HEAT rounds skidding/ricocheting, though this has been something I'm always researching (no answer yet!). I wonder if this is why the Bazooka had problems with the T-34 in Korea?


hartmann, tomo and I are discssing the PPS round, I thought you were too, sorry. It seems to have been developed for anti-armour performance though. What problems btw? ?(though I am guessing they may have been menioned already).



> The AT and Tank guns that used APDS got about a 30-40% increase in penetration and had to pay the price of Tungsten carbide use for that. Maybe you can fire a standard 75mm APCBC projectile out of a 105 barrel by using sabots but is it going to be any faster/better than a normal 75mm AT gun? And you have the bigger size/weight of the 105.



I meant the lighter APCR shell would have a higher MV? Your idea for a 75mm sub-projectile is a good one though ( would remove the need for tungsten), but IIRC the APCR penetrator wouldve been more like 40mm. Also, at this point, I'm not sure APC 75mm ammo was available? Again, this is a round for desperation - until the PaK 40 comes online in sufficient numbers ( for desperate self-defense).



> I think you are.



No I am not!! (though I do tend to lump the two together, as they are near as damnit).



> and the plates could crack right across



Wouldnt this make penetration easier? - though I suppose it would spread the load...

There are many advantages to a Cap, in addition to your points: It reduces ricocheting (esp. off sloped armour), and acts as a 'damper' or 'cushion'.



> It stressed a local point on the armor and weakened it and tended to push material aside rather than trying to shear out a plug like a high speed flat faced punch.



I think this may be where you may be getting confused. When vs tank armour, the projectile is better going into the interior (though the 'plug' will add to the damage). I suppose on ship armour it is the most important part?



> (around 2000fps ?)



Yup. IIRC I've heard 2600fps, but 2-3k fps is a good base. As I like to over-compensate, I like to work with 2k fps. 1250 fps is enough for steel LRPs though.



> the body would remain a bit softer but tougher (bend a bit before breaking).



This point you mention though apparently have some advantages when vs angled plates, but I'm not so sure...



> An HE shell body breaking up under the stress of impact and spilling it's load isn't really the same thing.



Even solid shots can break up though - /HE content just makes this worse. I think even 'shatter' and 'blunting' are 2 different things though - making 3 different effects under the 'shatter' umbrella.



> that device has 42 oz of TNT or explosive in it. or almost 1.2 kg. How much in a 105 shell?



No idea. - but I wouldve thought more than 5 or 6 potato mashers lumped together?



> Some accounts speak of trying to throw/place the charge on the engine deck/grates which are hardly 60mm thick.



Thats true, but I think it was just usually lobbed at the side armour? 45mm of vertical, brittle armour there, so?... It would at least immobilise it? Maybe even cause mechanical shock (stopping the engine/trans?).



> a mighty near miss. I think a 150-155 had to land under 10 yds away to have reasonable chance of disabling a tank and the 105s carried 25-33% of the explosive of a 150-155mm?



This would be easily achievable on a StuH (more likely a diret hit). A Wespe or LFH 18 though?... I think it would be possible?



> Well, you have to start somewhere and a look at the drawings shows why it wasn't very good. In 1938-1940 a lot of people knew the general principal which dated back to before 1900. It was turning this laboratory trick into a usable weapon that took a few years. The fact it wasn't issued in numbers and that the version which replaced it was only marginally better than the AP shot indicates the first version wasn't very good.



I remember the guy who invented the Bazooka got totally laughed at - but he was driven, and made a good presentation... KE was seen as the way to go. The Soviets were the only ones who ever really treated ( treat) HEAT as a viable ATG round. Perhaps its just National doctrine more than anything else? Of course, I believe the KwK 40 to have been a better weapon than the KwK 37 - but the KwK 40 wasnt available then... Again, its trying to make the most of what the Germans had at the time (KwK 37, LFH 18 later PaK 38 - but no KwK/PaK 40s; then later150mms, but no105/128mm ATGs). These methods were used though, which backs up my arguement, but what I want to know is, how well? Of course, you are right in saying that they arent ideal - but thats not the point I'm trying to debate.



> Not according to one source.



Which one is that please? 

I actually have found 105mm HEAT penetration figures, these are: 103, 116 128mm - for A, B C types. 

The short 75mm's, from the same source, are: 90, 96 128mm. Odd that the last 2 should be the same... (though the 75mm was considerd to need it more).

The longer 75mms also fired HEAT, but data for that doesnt come easy to had ( would be from a different source).

The source given is notoriously bad for HEAT data though, I should add, but it gives a rough view.

Still, it may be that 105mm HEAT performance was not much above the 75mms - but that would likely change, if the 105mm was developed to the same extent as the 75mm.

BTW, from that source, the 150mm 'A' shell is given as 206mm. ('C' shell was estimated on here as being 230mm, IIRC?).


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## schwarzpanzer (Apr 24, 2010)

Hi Shortround (Part 2),



> Lousy penetration. about 2 in or 50mm and you needed a 90 degree impact angle to get that.



More than enough to deal with a Panzer though? - except later PzIIIs turret glacis IVs glacis'.

I think it was OK, even @ that figure. The source above gives 89mm - enough to deal with a Tiger! (but horribly wrong, I take it?).



> Once you got through the 30mm armor of a MK III or IV with an angled impact did it really have much more effect inside the tank than an anti-tank rifle bullet



I think anything was better than the Boyes? (Though in Japan its greater accuracy might make it better?).


I hold 'shatter' as distinct from 'blunting'. Impact velocity is a big part of it, yes, but apparently overmatch and you really reduce the chances of this happening (maybe even nullify it?). Of course, I know that often it is not a problem (or was in WW2 even) - but I like to factor it in anyway. I think the lack of quality armour in WW2 is what allowed designers to get away with not factoring it in. Then again though, no tank (apart from the Tiger) really had armour that could usefully exploit this (exept for some PzIIIs maybe IVs).

Penetration in spite of shatter can happen - but I wouldnt like to rely on this, if I was a designer (?).



> At long range the dispersion is greater and more shells are going to be needed to get hits. The longer the range the more shells needed per hit. so how many shells per hit or tank knocked out is acceptable? also consider that for towed AT or open topped vehicles the longer the engagement goes on the greater the likelihood of the enemy artillery joining in. Depends on your HE shells, high explosives may be in shorter supply than steel, fuses aren't cheap and good HE shells require high quality steel. Mediocre ones don't.



I suppos it depends on the ranges, the ranges I propose are 1-2km, using direct fire (possible?). Indirect fire is something different altogether. I may create an 'Indirect Arty AT Fire' Thread later as I dont want this one to become bogged down with it ( its something I will find hard to understand - though hits on roof armour are guaranteed kills?).

Thank for the HE expenses info. I suppose thats another compromise.

Wrought Iron is still pretty brittle though? - but I suppose it depends on the quality? Why didnt they use malleable steel instead? (low carbon IIRC). I suppose its similar to a Katana? I know a plumber, I'll ask - though its all copper, lead or plastic think - no iron? I was actually a plumbers mate, and had hell on with a lead pipe once (was concreted in!).

Layered armour was tried in WW2 - on the Kleiner Tiger (baby KT). Katana-like armour got into mass production, on the Pz III apparently, Tiger.



> I am not sure but at the time it was considered that spinning the projectile (rifling) cut the ability of a given shaped charge design in half.



Thats probably, right, and a good way to remember it, thankyou. IIRC, I read that the RPG spun - can't be right?? - will need to check (thought it seemed wrong @ the time - which is probably why its stuck in my head).



> A source gives the HEAT penetration of the 15cm howitzer shell as 160mm so it should have the ability. But in WW II there was a fusing problem and HEAT shells wouldn't function properly at high impact velocities. In some cases the heat shells were fired at less than full charge even by howitzers. So you have the ability to penetrate IF you hit but a lower chance to hit at ranges over 500meters and the chances get worse the longer the range.



Sorry, I meant LFH 18 (105mm). HEAT shells are never meant to strike @ high velocities - a gunner who knows what hes doing will not often use them above 500m.

I think the KwK 37 had a max range of 1,200m - maybe more with a very good gunner (even upto 2km maybe). Still, this is mostly using 'bracketing' techniques though - lots of ammo expenditure. I would expect the LFH 18 to do better though?



> Not only were some later Japanese tanks more heavily armored (Type 97) but single penetrations of vehicles by even 12.7-14.5mm bullets doesn't lead to destruction in most cases.



Thanks for the Indian HEAT info. Grants used 75mm AP shells against bunkers - so I think this would be their intended use (though AT work would be interesting, but pointless - unless vs German vehicles, which you said didnt happen - pity!). I would expect a Boyes to keep shooting (but its recil was terrible). It was a really poor weapon, but still useful here (an AT backwater). Jap tanks were cramped though - riveted, which would help. They were so cramped that they required padding! (but were thus a small target - no problem for the accurate Boyes?).



> schwarzpanzer said:
> 
> 
> > Doesn’t it also degrade HE performance though?
> ...


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## schwarzpanzer (Apr 24, 2010)

Hi Shortround (Part 3 - sorry, almost missed this one),



> Quote:
> Originally Posted by schwarzpanzer (Part 3).Arty HE fire doesn’t depend on sights so much though? – rather plotting corrections from an observer?



Sorry, it would appear your answer to this has been lost.



> loading 40-50kg projectiles vs 25kg projectiles? book figures for towed howitzers list same rate of fire 3-4 per minute but that is with a large gun crew.



Thanks, but the German 88mm had a higher RoF than a 7.62mm NATO rifle bullet! (apparently in certain circumstances).

The later D-25T improved the RoF much further. Do you think those Wikipedia figures are wrong? How many loaders for the towed versions?



> Yes it was, but this needs a thread of it's own.



I heard that from a guy whos relative fought in the war. For e.g. DYK that the T-55s had night vision - but the Centurions didnt? The T-55 was later upgraded by the Israelis, but the base models were better too. They were too small for Israeli crews though.



> It depends on original design. If you are trying to fit synchros into an existing gear case you have to make the gears thinner and less strong.



I have experience with 2 boxes - the 1st was designed in the 1950s (or even earlier) so OK, but the seccond was more like the 80s. "Shouldn't" and "much"?... Would dog-engagement (?) be OK for a tank? Do Preselectors use Synchro? Is Synchro redundant in a Preselector? I suppose Spur gears will create a constant whine though - but IIRC bigger gears cause less, rather than more noise? Plus, you have that bulkhead... (though not in the Panzers). Perhaps Helical gears on final drives only? Spur gears are also much easier to manufacture? (though once setup, it wouldnt cause much difference - for the production levels wanted?). 



> If you are designing from scratch and transmission case size is unrestricted there shouldn't be much problem.



I think a smaller transmisson is better - to reduce external vehicle dimensions /or interior room?



> With low rpm engines you have less over lap of gears. I drive a 34 ton fire truck with a 450hp engine and a 4 speed automatic. While much faster than a tank I think the same principles appliy. Max engine speed is 2200rpm. While it will do 55mph on the level it often is down to 30mph on hill, max rpm in second gear, 1st is good for 15mph. if it shifts to 3rd gear on the hill it is below it's torque and power peaks and can't rev up. More gears mean more options and better mobility in less than flat smooth conditions.



You actually have a fire engine? Swank!  Theres a joke based around that, wont say it, as you may not get it (but last time I used it on an AMerican, he understood). Anyway, back to seriousnessness You're truck will have a lower rolling resistance (about the same that the soles of your feet have). The power and rpm levels are very similar though, and would be useful for comparisons. BTW, do you have the torque levels, hp levels of your engine - @ rpms? It would be very useful for these discussions!8) The rolling resistance of tracks is much higher than your tyres - on one hand it hurts top speed (which is why your truck ha higher top speed), yet when it comes to hills, that rollin resistance is lessened, equated into sheer inertia-beating traction, something your truck could never come near - if it had more power, it would just spin its wheels. Of course, momentum is desireable in a tank too (but less vital). There is a nasty little trick that yuppies like to do to vehicles such a yours in the UK.

Too many gears can cause headaches too, apparently, 3rd gear is the most often used in a tank, but I would say 4 gears is enough? I wonder how many the M18 Hellcat had?...

Power spreads are a different matter...



> Other things that can affect tank speed are the rolling resistance of the track itself, some designs had twice the rolling resistance of others and track tension. slack track having less rolling resistance. But each of these choices have there down sides too



True, but this is not something I often have had to bother calculating (though I can, really should've). What are the plusses minuses on tracks btw? Do you happen to have data on calculating tank rolling resistances? (I suppose I could figure it out myself though - I might have to make a spreadsheet!).

Do you mean rolling resistance vs grip ground pressure?


----------



## Shortround6 (Apr 25, 2010)

schwarzpanzer said:


> 1. Attacking targets out in the open - such as ATGs, infantry etc. This often means not a direct hit, often relies on frag blast effect. I expect this could disable tank tracks? (if very close - which is possible on a tank @ long range, as are even direct hits).


For those targets close was good enough, a direct may have been a bonus. But for disabling tanks you need a lot more luck, and effect on tracks is related to the size of the shell and the size of the track. It's a lot easier to break the track or break the road wheel of a Bren carrier that a Tiger tank


schwarzpanzer said:


> 2. Attacking buildings and bunkers etc. Now this is where I fall down. As I see it though, the explosive detonates on contact and rips the target apart - I would expect the same to happen to metal plates, if they were brittle or thin enough, or badly joined. I know about HESH, but I would expect HE to work slightly similar? (only with less velocity on the 'scab').



HE worked better if it could penetrate, even if only part way. Think of trying to blow a brick building up (or down) with just a few pounds of explosive. Explode it outside, a few feet from the building? Put it inside one of the rooms? or drill a hole in the wall and put explosive in the wall? 

HE against tanks will not form scabs if there is any real distance (air space) from the explosion and the armor.


schwarzpanzer said:


> 45mm sloped @ 60 degrees. Aprox 60-70mm @ round IIRC (turret front). Turret sides rear were somewhere inbetween (all aprox equal). 'Shell-proof' was actually referring to 76.2mm Soviet AP shells - not just artillery fragments (which the pre - shell-proof BT could keep out).


according to one book the 25mm armor of the A-20 prototype satisfied the 'Shell-proof' requirement.



schwarzpanzer said:


> - but I used it to hopefully illustrate that a smaller, higher velocity weapon, such as a SiG-33 could easily destroy a single Sherman with a direct hit?



that things COULD happen isn't in dispute. That such happenings are the basis for good vehicle design or possible tactics are. 

Consider that the SiG-33 has a MV of 240M/s with max charge for the HE shell. This means about a 265 meter point blank range. Point blank range being the distance (given a suitable elevation) that the shell will neither pass over or hit below a normal tank sized target. A standard 75m Sherman has got a point blank range about 2 1/2 times further. A Sherman gunner could simply set his sight for about 500m meters or so and be fairly confident of a hit (somewhere on the enemy tank) out to around 680meters. aiming at a particular point on the tank takes a bit more refinement.
Our German gunner at 600 meters distance, if he misjudges the range by just 25 meters or so will either shoot over or under the Sherman ( under might not be so bad but lobbing the shell over the top isn't likely to throw the Sherman gunner off that much). Then the Sherman with it's much faster firing gun gets 2-3-4 "free shots" while the SiG -33 is being reloaded, or moves a hundred meters 

Giving such guns AT ammunition in case of emergency is one thing. trying to use them as part of a planned anti-tank defense is a poor use of assets.


schwarzpanzer said:


> Of course HE isnt ideal for Anti-tank use, but if its all thats available... I'm trying to find out just how useful that was. BTW the 1st tanks to be destroyed (in WW1) were very likely destroyed by HE shells.



It 150mm howitzers are all that is available then the battle plan has gone seriously wrong and you are trying for a miracle solution of near biblical proportions to save it. 
BTW the tanks in WW I were destroyed by HE shells but then the WW I tanks had armor of about 8-9mm in thickness and none too great a quality either. A dud HE shell could punch through it. 


schwarzpanzer said:


> I was thinking that, as the KwK 37 had a high trajectory, that the shells would not hit it flat-on..... True that variations in rounds would also have hindered though - but was it really that bad?


 The difference in trajectory can be amazing but the difference in hit angle isn't that great. one degree equals 5 ft at 100yds. so for a two degree change in impact in your favor your projectile would have had to be about 10 ft higher than the point of aim at a little less than 100 yds out. Now figure the target is not sitting on a billiard table but maybe siting on a bit of an angle itself and may not be facing you square. Armor penetration figures given in most tables are an average of 10 shots or so depending on nations test procedure. 


schwarzpanzer said:


> I wonder if this is why the Bazooka had problems with the T-34 in Korea?


I don't know but consider that if the Bazooka had a proving ground figure of 120mm and hit a 45mm plate at 60 degrees it actually has to penetrate 90mm of armor by geometry. throw in a little skid and/or not hitting dead on in horizontal plane and the margin becomes even narrower. How much over penetration is needed to have a telling effect?


schwarzpanzer said:


> I meant the lighter APCR shell would have a higher MV? Your idea for a 75mm sub-projectile is a good one though ( would remove the need for tungsten), but IIRC the APCR penetrator wouldve been more like 40mm. Also, at this point, I'm not sure APC 75mm ammo was available? Again, this is a round for desperation - until the PaK 40 comes online in sufficient numbers ( for desperate self-defense).



If you have enough time to design, test, develop and manufacture trick ammo, shouldn't you have enough time to produce real anti-tank guns?
The full bore 10.5cm AP projectile was enough to handle everything but a Matilda (and there weren't that many of them) up until 1941. 




schwarzpanzer said:


> No I am not!! (though I do tend to lump the two together, as they are near as damnit).
> 
> Even solid shots can break up though - /HE content just makes this worse. I think even 'shatter' and 'blunting' are 2 different things though - making 3 different effects under the 'shatter' umbrella.



To keep things straight, shatter is what happens when the hard point of the projectile shatters or breaks up on hitting the armor, blunting if you like because that is what happens. like trying use a blunt knife or dull drill. The shell body breaking up is different. The shell walls were not strong enough to withstand the compression forces (still moving rear of shell pushes the shell walls behind the rapidly stopping shell nose). It may be possible to have a broken shell body with a relatively intact nose.



schwarzpanzer said:


> No idea. - but I wouldve thought more than 5 or 6 potato mashers lumped together?
> 
> Thats true, but I think it was just usually lobbed at the side armour? 45mm of vertical, brittle armour there, so?... It would at least immobilise it? Maybe even cause mechanical shock (stopping the engine/trans).



German 10.5 howitzer shell had just over 48oz of explosive. The Grenade used a time fuse. Pulling the string out of the handle ignited a compound like the head of a match which in turn lite a burning fuse. timing was approximate, 4-6 seconds? timing your throw for impact detonation would require large amounts of luck. throwing too soon and the charge could bounce/ roll off and explode on the ground, throwing too late could mean "Hans" get caught in his own blast. Trying for the engine deck means it might not roll off or if placed there means "Hans" has 4-6 seconds to get away.



schwarzpanzer said:


> I remember the guy who invented the Bazooka got totally laughed at - but he was driven, and made a good presentation... KE was seen as the way to go. The Soviets were the only ones who ever really treated ( treat) HEAT as a viable ATG round. Perhaps its just National doctrine more than anything else? Of course, I believe the KwK 40 to have been a better weapon than the KwK 37 - but the KwK 40 wasnt available then... Again, its trying to make the most of what the Germans had at the time (KwK 37, LFH 18 later PaK 38 - but no KwK/PaK 40s; then later150mms, but no105/128mm ATGs). These methods were used though, which backs up my arguement, but what I want to know is, how well? Of course, you are right in saying that they arent ideal - but thats not the point I'm trying to debate.



Bazooka warhead was from a "rifle grenade" design for the .50 cal machine gun. Not very practical.
Russians use/d HEAT because for many years their guns/propellant wasn't up to western standards and they could not get the velocities of KE projectiles up to western levels for a given gun size. National doctrine?

Again, using your divisional, corp or army artillery as anti-tank guns in the front or even second lines of defense is a gross miss use of the asset. Most Armies didn't have enough of them to begin with (except maybe the Russians).
From a tactical standpoint they are large, difficult to dig in/emplace, almost immovable once combat starts, have low rates of fire and with their heavy barrels have difficulty tracking moving targets even if their carriage has enough traverse.


----------



## Shortround6 (Apr 25, 2010)

schwarzpanzer said:


> (Part 2),
> More than enough to deal with a Panzer though? - except later PzIIIs turret glacis IVs glacis'.
> I think anything was better than the Boyes? (Though in Japan its greater accuracy might make it better?).



British introduced it in 1940 and were getting rid of it in1941 except for "home guard" use which ought to tell us something about what they thought of it. 

A classic case of "shatter" was the US 76mm gun in France. It was called the "Shatter gap". At close range it was discovered the gun could penetrate the front of Panthers and as the range lengthened it could not. Pretty standard right?
Except that as the range lengthened a bit more it started penetrating again and then failed as the range got even longer. The explanation (judge for yourself) was that at close range (0-200yds?) the gun over matched the Panther armor enough that the projectile went through anyway. at the 200-6/800yds(?) ranges the point shattered in spite of the cap and failed to penetrate. At over 6/800yds(?) the velocity had fallen to where the point did not shatter and everything worked as designed and the projectile penetrated. extend the range a bit more (another few hundred yards)and velocity (and energy) had fallen to point where the projectile no longer penetrated. 



schwarzpanzer said:


> Wrought Iron is still pretty brittle though? -


It depends, saying wrought iron is a bit like saying steel, it varied in actual composition and in how it was worked so it's tensile strength and other properties varied quite a bit. It is possible to bend wrought iron railings quite a bit before they break. 



schwarzpanzer said:


> Sorry, I meant LFH 18 (105mm). HEAT shells are never meant to strike @ high velocities - a gunner who knows what hes doing will not often use them above 500m.



Perhaps for the same reason as the British 25pdr gunners held fire until 400yds or so. With their slow rates of fire and low chances of long range hits they had to take the enemy by surprise and inflict losses with the first shots. engaging in a long range "ranging dual" with the faster firing tanks was a loosing game. The tanks higher velocity guns meant range estimation was less critical, the higher rate of fire meant more feed back on errors quicker and near misses by HE shells on AT guns had a much greater effect on the un-armored AT gun crew than a near miss would have on the tanks


schwarzpanzer said:


> I think the KwK 37 had a max range of 1,200m - maybe more with a very good gunner (even upto 2km maybe). Still, this is mostly using 'bracketing' techniques though - lots of ammo expenditure. I would expect the LFH 18 to do better though?


There were a few occasions of long range duals in dessert with each side using HE (Grants vs MK IVs) with each side hoping to reduce the opposition's numbers before closing range and deciding the engagement with AP ammo. The Germans had used this tactic against the British before the Grant showed up to advantage but it rarely affected the battle (except to lower morale of the British, hard to take fire and not be able to shoot back) . The LHF 18 might be able to do 15-20% better than the KwK 37 but neither are that great even compared to a Sherman gun. 




schwarzpanzer said:


> Thanks for the Indian HEAT info. Grants used 75mm AP shells against bunkers - so I think this would be their intended use (though AT work would be interesting, but pointless - unless vs German vehicles, which you said didnt happen - pity!). I would expect a Boyes to keep shooting (but its recil was terrible). It was a really poor weapon, but still useful here (an AT backwater). Jap tanks were cramped though - riveted, which would help. They were so cramped that they required padding! (but were thus a small target - no problem for the accurate Boyes?).


The 20lb HE shell might have performed better against bunkers than the lighter Grant shell. One source gives an HE filling weight of 2 lbs which is about double that of an american 75mm shell. 
Yes the Boyes would keep shooting, point being that the Boyes can't relied upon to stop the Japanese tanks although it can get some of them. 



schwarzpanzer said:


> A very good point. 400-600yds is scary! I read though, that if the Pont Du Fahs 6pdr gunners had've opened fire at ranges below what they did (aprox 500m) they would not have suceeded. I found an awesome article on this ( shatter-gap), that I posted here in about 2006, but I cant find it for love nor money! (deleted?).



As far as the 6pdrs go because of their much higher velocity they could engage from longer ranges than the field artillery guns. 

and as far as shatter goes See:

6 Pounder Anti-Tank Gun

Please note the differences between capped and uncapped projectiles against the two different types of armor. In some of the North African battles the early 6pdrs with UNCAPPED shot may very well have had trouble with face hardened armor. With capped shot supplied face hardened armor seems to have been tamed. 


schwarzpanzer said:


> True. The PaK 36s rounds were APCBC though - but I suppose you design to defeat your own armour really (strange, but true!). The lack of /HE in the 2pdr allowed much better penetration than the German 37mm (pity about the shatter/quality). Later spaced armour on the PzIII IV disabled Caps btw... - could tumble AP rounds too.



Going by Ian Hoggs book the Pak 36 rounds were not capped but he could be wrong. Allthough pictures seem to show an uncapped projectile.

http://www.quarry.nildram.co.uk/tank1.jpg

The lack of HE had little to do with the 2pdrs penetration. The much heavier projectile (1077 grams vs the German 37's 680grams) and a higher velocity means that the later 2pdr ammo had 392,000 joules of muzzle energy compared to 200,000 joules for the Pak 36. 



schwarzpanzer said:


> - but it wouldnt start a fire?... Youd need the incandescent penetrator for that. If the armour 'tore' - then youd get no 'plug'?.



Again with the fire? if you kill the crew you don't need fire. and you don't need an incandescent penetrator. the metal from the plug is going to be several hundred degrees or more. you don't shove a sizable plug of metal out of an metal plate without creating some heat. If the chunks of metal are big enough and they fall into stored ammo they have been known to start fires.



schwarzpanzer said:


> Thanks for the info. So you're in agreement then? Wonder if we've any AA Arty fans on here? Rommel was often hated by the Luftwaffe for stealing their guns for 'improper use'. It seems he was 100% right though? What about the 3.7in 'Morale' guns in Britain? Still, AAA was apparently very useful against V1s.



Uh, no, not in agreement. I am pointing out you can't use AA guns in a forward position. If you want them as AA guns they have to be deployed where enemy artillery can't reach them. Some people think that Rommel, if not 100% wrong, went a little too far in stripping his AA assets. While it does take thousands of AA shells fired to bring down one bomber (cost trade?and this was known either before the war or very soon after the start) it can be said your AA defense has worked if your enemy has failed to get his bombs on target even if he has had no planes shot down. Would Rommel have gotten more supplies through if his 88s had been doing their AA job? A question we probably can't find the answer to. 

Properly sited AA guns, connected to fire control predictors with range and hight finding instruments (optical or radar) and up to date meteorological conditions are not "Morale" guns. it may take them several thousand rounds to bring down a bomber but they are a valuable (all weather, round the clock) part of the defense. Sited by themselves with no predictor (gun director, in navy terms) or fuse setting information they become "morale" guns. Aiming and fuse settings depending on the gun captains judgement and a wetted finger held up to the wind they make a satisfying "bang" on the ground and a black puff in the air but success goes into truly astronomical chances


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## Shortround6 (Apr 25, 2010)

Part 3 



schwarzpanzer said:


> Thanks, but the German 88mm had a higher RoF than a 7.62mm NATO rifle bullet! (apparently in certain circumstances).



Yes," circumstances"  Did the 7.62mm NATO rifle have a semi-automatic breech block and a loader?


schwarzpanzer said:


> The later D-25T improved the RoF much further. Do you think those Wikipedia figures are wrong? How many loaders for the towed versions?


Crew is given as 9 for the towed version, not all are loaders and the ammo has to a moved a greater distance. Changes in breech mechanism may speed things up. Field artillery usually has a manual breech. Somebody in the crew has to manually flip a lever to open the breech block and extract the casing. After the shell and powder charge/casing are rammed into place the same crewman has to close the Breech. Tank guns use semi-automatic breech blocks (usually) where cams operate the breech block during recoil and **** a spring, when the loader rams in the cartridge case the rim trips a catch and releases the spring powered breech block to slam shut. 



schwarzpanzer said:


> I heard that from a guy whos relative fought in the war. For e.g. DYK that the T-55s had night vision - but the Centurions didnt? The T-55 was later upgraded by the Israelis, but the base models were better too. They were too small for Israeli crews though.


Since both tanks had careers that spanned over 30 years and had many variations you kind of have to match them up version to version. The T-55 was too small for some Russian crews too. Somebody once said of the of the T-54/55 series "when the Russians run out of strong, left handed midgets they are going to be in trouble"  



schwarzpanzer said:


> You actually have a fire engine? Swank!



I don't "have" one I Drive one. It's my job. Some of the first Fire trucks I drove were crash boxes and old ones at that. This is a picture of the current truck;

Truck 1



schwarzpanzer said:


> The rolling resistance of tracks is much higher than your tyres - on one hand it hurts top speed (which is why your truck ha higher top speed), yet when it comes to hills, that rollin resistance is lessened, equated into sheer inertia-beating traction, something your truck could never come near - if it had more power, it would just spin its wheels. Of course, momentum is desireable in a tank too (but less vital).



We don't go off-road.  if you think you can spin the tires, eight powered 11.00x 20.00s on the rear bogie going up hill on pavement you are going to need a lot more power. an awful lot more power. 

You don't need to tell about momentum, between that and the turbo lag little old ladies with walkers beat us across intersections from a standing start.


schwarzpanzer said:


> Too many gears can cause headaches too, apparently, 3rd gear is the most often used in a tank, but I would say 4 gears is enough? I wonder how many the M18 Hellcat had?...



I would say it depends on power to weight and expected terrain. flat areas need fewer gears than hills.
The Hellcat had 3 gears forward but the torque converter expands the spread quite bit. Torque converters multiply the torque when the input shaft is turning faster than the output shaft until road speed picks up enough that the shaft speeds equalize. Depending on the torque converter you can around double the torque at when the converter is near stall (output shaft near stationary). The WW II torque converters always slipped some but later ones (fire truck included) have "locking" torque converters for better fuel efficiency. sort of makes the 4 speed automatic act like an 8 speed as you watch the tachometer needle.



schwarzpanzer said:


> Do you mean rolling resistance vs grip ground pressure?



No, I mean that slack tracks (loose tracks) have less rolling resistance but are more prone to shedding on turns or in bad terrain.


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## schwarzpanzer (Apr 28, 2010)

Hi tomo,

Sorry, I forgot to reply to your last post, so it's out of order. (hartmann Shotround, you're next. ).

Thats a good point on the ZiS-2s barrel wear. It would have been more expensive because it was a new calibre, probably? - but the construction of the gun itself was very 'Sten-like', so was used to reduce the price of the 76.2mm - the carriage, that is, dunno about the gun. Someone else on here has posted that APCBC was very expensive for the D-10, so maybe it was for the ZiS-2 too? - explaining the higher price (especially per shot). That also explains why the D-10 didn't use APCBC so much - the 57mm was a new calibre, so new ammo could be developed - which was not the case for the old 100mm?

I think the ZiS-2 got a 'second wind' though, and was considered better than the 45mm L66? (Thanks for the info).

It was used in T-34/57 SU-57 tank destroyers, after all - a serious weapon!8)

I suppose its main problem was in being a solution to a problem that didnt exist - then did. Still, better to have something, not need it than...?

100mm info has been posted by Shortround, I'm sure its something we'll get to the bottom of!



> I don't have problems reading Serbian forums sites, while my country ( me) was in was with them 15 years ago.



Thats a very good attitude to have IMO, and I respect you for it.



> You can take a look at this drawing, with turret almost half of height of KV-2's turret:
> KV-1 (107mm gun)



Thanks, very good. I'll have to study KV prototypes more. Battlefield.ru has a good page on it. I dont know whetherthe Beast of Leningrad was a prototype, or a hurriedly re-gunned KV-2 (both turrets look similar). Unfortunately, theres no real good ifo on the net.



> My take would be, production versions:
> -one version of IS-1 (85mm)



Thats probably about right - there was a 100mm gun version - but it may not have seen service. (The /85 apparently did though).



> -two versions of IS-2 (the second version featured glacis plate of constant slope, not cranked)



This is where it might get confusing! The 1st ones were re-gunned IS-1s ( prototypes). There may have been those with the cranked/stepped glacis that were originally built as IS-2s, but I dont know. The 1944 model (sloped glacis) was a production IS-2 at least! There was a proper IS-2M - post-war refitted IS-2s. I think there were 2 version of these?: 1 with the stepped glacis, 1 with the cranked. The info should be on Wikipedia IIRC?



> It was good, but not ideal IMO



So long as ATGs were not encountered, it was fine!  The obsession with putting such a big gun on turned it into a bad design IMO.



> That's vague point...



Lots of drivers commented on it, theres a DVD with a mechanic of one in a Museum saying how bad it was. I don't know if the DVDs available in Croatia? Is there a Croatian Amazon? Anyway, it's called 'Killer Tanks KV'. - a very good DVD! (Also includes pre- post- KV - such as the SMK (IIRC) the IS-2 IS-3). Its cheap too (in the UK).


Thats good info on the KwK 36, thankyou. I think though that HE shells were a lot lighter than AP shells – making for a bigger recoil than HE. Also, I think maybe that HE rounds may have had a reduced load in the cartridge? – further reducing recoil. 

The KwK 36 was biased towards AT performance – the 85mm was more evenly balanced.



> perhaps the Russkies have done better job converting AA piece to AFV use?



Yes, I think the 85mm should have been much better – it was massively downgraded from its base AA design – whereas the KwK 36 was apparently upgraded ( the 88 had more power than the 85 in the flak role to star with, IIRC). Whether the 85 was cut down to be put on the T-34 I dont know - but it was mouted on the SU-85 1st, the T-34 could almost handle the 100mm, so I dont think so - perhaps the designers were being over-cautious? If it wore the tank out quickly then thats not a problem - as T-34s didnt last that long. Thinking about it though, it was on the KV/85 1st - so maybe problems occured there?



> Hmm, the arrogance tends to backfire...



Yes, that often happens - never underestimate your enemy IMO.



> Not superior; perhaps even, and that only until Centurion received 105mm.



The 20pdr was found unable to cope (by the British) - hence the 105mm L7, mobility and protection were also far ahead. Optics were not that inferior - even to the 105mm, apparently.


An MBT?, thanks. - yes, this was starting to appear in WW2. Whether the T-34 can be considered one - or the Panther? Tank designations can get confusing at this time - with several different answers.



> Shove the Maybach on 'our' KV-88/Panther and you have 30 mph pronto



I'm afraid it mght not be as easy as that - the small, steel wheels would be unsuitable for 30 mph - and would probably stress the engine even more than in the Panther - with its large dia wheels. Steel wheels proved unsuitable on both the Panther T-34 btw. For a heavy tank though, the design would be fine.



> That's theory (even if I find some points debatable).
> Practice says all-aft layout was better - and it dominated the tank world for some 60-70 years.



I think it only really became practical after the introduction of automatics (even then causing problems in the M6 M26). The Centurions crash gearbox was a pain, as was the T-54s IIRC? The T-34s was hard, but I'm not sure in the Cromwell/Comet - perhaps in lighter vehicles its acceptable? I wonder if you could have an all-aft Preselector setup? - Shortround?



> By what accounts it was 'more modern'? The 60 degs are hardly magic, with 30 I'll agree...



Sorry, 60 degrees from vertical, not horizontal. I prefer to use vertical as a starting point when discussing armour.



> You can read the Russian accounts when they've tested Pz-III(E?) and T-34 - Pz-III was faster (almost 70 km/h), with 5 crew members vs. 4 of T-34, better ergonomics radio of Pz-III...
> Of course, T-34 have had better gun, much better protection off-road performance.



True, the T-34 was better in 'hard' areas of design, but < in 'soft' ones.

I thnk 70kph sounds a bit suss? The T-34 was developed to be more like the PzIII anyway (but far to late IMO).



> The road wheels were replaced with ones with bigger radius.



I'll have to check that... I know they were lighter, anyway - reducing all-up unsprung weight (increasing off on-road performance comfort).



> Too bad the Brits haven't found the way to convert pre-war 3in AA piece for AFV use in greater numbers; that one would've lay waste in N. Africa.



Actually, they did! - It was mounted in the hull of a Churchill - but onlyused for home defense, rejected. Britain failed to make a good tank destroyer - too obsessed with turrets. The Archer was an attempt though.



> OTOH, Commonwealth forces suffered mostly in time Axis forces were equipped with Pz-II Italian tinclads, proving (again) that there is no remedy for bad tactic strategy (save the numeric advantage).



True, but at this time they had very vulnerable A9, A13 A15 Cruisers MKVI Lights.



> Think from Normandy on



Thanks, I'll have to keep my eyes peeled for that. Strange I've never heard of it before though. The Fougasse was supposed to be to attack tanks IIRC - so I suppose it makes sense.


----------



## tomo pauk (Apr 28, 2010)

schwarzpanzer said:


> Hi tomo,
> 
> Thats a good point on the ZiS-2s barrel wear. It would have been more expensive because it was a new calibre, probably? - but the construction of the gun itself was very 'Sten-like', so was used to reduce the price of the 76.2mm - the carriage, that is, dunno about the gun.



It was the barrel that was expensive IIRC, a problem further emphasized by notable barrel wear after not-so-many rounds are fired.


> Someone else on here has posted that APCBC was very expensive for the D-10, so maybe it was for the ZiS-2 too? - explaining the higher price (especially per shot). That also explains why the D-10 didn't use APCBC so much - the 57mm was a new calibre, so new ammo could be developed - which was not the case for the old 100mm?



For the history of Russian ammo I'm not the good source 



> I think the ZiS-2 got a 'second wind' though, and was considered better than the 45mm L66? (Thanks for the info).



The difference in performance is akin to the difference between 5cm pak 7,5cm pak (yet, both Soviet ATGs (45L66 57mm) were light enough for manhandling).



> It was used in T-34/57 SU-57 tank destroyers, after all - a serious weapon!8)
> I suppose its main problem was in being a solution to a problem that didnt exist - then did. Still, better to have something, not need it than...?



Soviets were looking for a multi purpose tank gun, so 76,2mm served them better. Still, too bad they didn't make any more of T-34-57 than token numbers. Not only to tackle Tiger Panther, but to beat older, but improved German AFVs (mainly Pz-IVG/H StuG-IIIF/G).



> This is where it might get confusing! The 1st ones were re-gunned IS-1s ( prototypes). There may have been those with the cranked/stepped glacis that were originally built as IS-2s, but I dont know. The 1944 model (sloped glacis) was a production IS-2 at least! There was a proper IS-2M - post-war refitted IS-2s. I think there were 2 version of these?: 1 with the stepped glacis, 1 with the cranked. The info should be on Wikipedia IIRC?



I recommend onwar.com wwiivehicles.com for a quick online reference, but people do tend to look at Wikipedia for that 


> Lots of drivers commented on it, theres a DVD with a mechanic of one in a Museum saying how bad it was. I don't know if the DVDs available in Croatia? Is there a Croatian Amazon? Anyway, it's called 'Killer Tanks KV'. - a very good DVD! (Also includes pre- post- KV - such as the SMK (IIRC) the IS-2 IS-3). Its cheap too (in the UK).



What's the name of the DVD? 
Amazon does ship internationally...



> Thats good info on the KwK 36, thankyou. I think though that HE shells were a lot lighter than AP shells – making for a bigger recoil than HE. Also, I think maybe that HE rounds may have had a reduced load in the cartridge? – further reducing recoil.



We can draw parralels between AP ammo too, but the net result wouldve been about the same.
The Soviets did have reduced load for HE shells of their 45mm, albeit with heavier shell - good concept. Think that Italians did the same with Bohler (47mm). 



> The KwK 36 was biased towards AT performance – the 85mm was more evenly balanced.



Don't think so. Both 'sets' of engineers tried to extract as much of the reliable performance as possible, and I do think both cannons were geared towards good all-around performance (and succeeded in it).


> Yes, I think the 85mm should have been much better – it was massively downgraded from its base AA design – whereas the KwK 36 was apparently upgraded ( the 88 had more power than the 85 in the flak role to star with, IIRC).



85mm tank gun have had the same muzzle energy as 85mm AA gun (with same round), so no downgrade there 
Sure enough about AA performance, 88L56 have had greater muzzle energy (up cca 20%?)


> Whether the 85 was cut down to be put on the T-34 I dont know - but it was mouted on the SU-85 1st, the T-34 could almost handle the 100mm, so I dont think so - perhaps the designers were being over-cautious? If it wore the tank out quickly then thats not a problem - as T-34s didnt last that long. Thinking about it though, it was on the KV/85 1st - so maybe problems occured there?



Don't think there were any problems with 85mm aboard those hulls.


> I'm afraid it mght not be as easy as that - the small, steel wheels would be unsuitable for 30 mph - and would probably stress the engine even more than in the Panther - with its large dia wheels. Steel wheels proved unsuitable on both the Panther T-34 btw. For a heavy tank though, the design would be fine.



If those 30mph are achieved on the road, think smallish wheels wouldn't present a problem. Off road, the max speed would have been reduced anyway.



> Sorry, 60 degrees from vertical, not horizontal. I prefer to use vertical as a starting point when discussing armour.



That makes sense 



> Actually, they did! - It was mounted in the hull of a Churchill - but onlyused for home defense, rejected.



I know, that's why I've said 'in greater numbers' 



> Britain failed to make a good tank destroyer - too obsessed with turrets. The Archer was an attempt though.



They might have tried to mate it (3in) with hull of M3 (Grant).


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## Shortround6 (Apr 28, 2010)

"They might have tried to mate it (3in) with hull of M3 (Grant)."

It was done. It wasn't pretty.

Google Image Result for http://mailer.fsu.edu/~akirk/tanks/UnitedStates/selfpropelledguns/usspg-T24-a.jpg

Scroll down to the T24 and the T40 

for real giggles see the T1/M5

OK it wasn't a British 3in gun but be careful what you ask for,

You just might get it


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## tomo pauk (Apr 29, 2010)

Not very pretty 

I wast thinking along the lines of an 'American StuG', or 'American SU-85' (US-85?  ), but this (M3 with 3in) does look rather Marder-ish...

The other ones you post about are pretty ugly, though I like US self-propelled pieces.


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