# Heer, from january 1936 on?



## tomo pauk (Nov 7, 2014)

Same drill as other thread - how to make the mighty German Army even a bigger juggernaut? The major historical events (anschluss, Czechoslovakia, Poland, up to the attack on the Soviet Union and North Africa prior 1942) unfold as historically, of course.


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## gjs238 (Nov 7, 2014)

They need more, many more trucks.
More fuel for those trucks.
Ways to protect all that fuel.


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## tomo pauk (Nov 8, 2014)

A wider introduction of diesel engines should save lots of fuel, even if it is issued 1st on trucks, later on AFVs. The majority of the Heer would still be away from a complete motorization, though, let alone the mechanization.

Small arms - generally historical stuff was highly regarded. The earlier introduction of a self-loading and/or automatic rifle based around a 'mid-power' cartridge, like they have had the 7,92mm Kurz should be an useful addition. The StG-44 was a great weapon, but too late to matter.

Mortars - earlier introduction of the 120mm, not waiting for the Soviets to teach us a lesson.

AAA - a strong suite historically. Maybe an earlier introduction of a 30mm (single, twin or quadruple, both towed and SP), should outrange the 20mm by a good margin, while being powerful enough to really hurt even the most resilient aircraft. The 30mm AAA in German service in ww2 was a case of too few, too late.


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## Shortround6 (Nov 8, 2014)

We are back to what could have been reasonably done in 1936 vs taking 1943-44 designs and trying to make them in 1936/37.

The Germans were actually pretty well off as they could build new weapons and didn't have warehouses full of left over WW I Junk that kept people from OK'ing new weapons.

Artillery was at least workmen like even if only a few guns were outstanding. 
I agree that small arms were good, main failing being the Mauser 98 but then only the Americans were switching to a semi-auto in any numbers, Russians had one but not in large numbers in relation to the size of their army. 
Perhaps a semi-auto using the 8x57 round issued to two men per squad to beef up the rifle team? 
For a lot of German weapons, a larger weapon increases the logistics problem. 
In theory (or company sales brochures) you can man pack a 120mm mortar





But in actual practice?
and 120mm mortar ammo _can_ weigh 45kg for two rounds in a wooden crate. Not including fuses or propelling charges. 
http://mirex-ds.com/products/ammunition/Ammunition Mortar Round 120mm High Explosive.pdf

64 rounds + 64 fuses + 76 propelling charges weighs 1557kg. You are not going very far without engines, horses or a _LOT_ of men. 

Germans might have shifted to dual 20mm AA guns a lot sooner, perhaps they thought the improved rate of fire of the M38 was just as good? 

In any case the 30mm AA guns in use at the end of the war were the MK 103 guns and not the slower firing MK 101 guns. While the MK 101 may have been better than the Flak 38 you start getting into target effect vs weight of weapon/carriage. 

One point of easy change was the 37mm AT gun, It was the first of it's generation (pretty much, first guns were issued in 1928 ) and as such had the poorest performance. As such it _should_ have been replace the soonest. Russians stuck a 45mm barrel on the same carriage in 1937 and got roughly the same performance using standard ammo as the Pak 37 got with tungsten cored ammo. HE performance was better too
The story of the 37mm being kept for the MK III tank but with a larger turret ring is well known.

Germans do have the same problem as many other countries. The very rapid increase in the _size_ of the armies made it very hard to change weapons as interruptions in production meant delays in issuing weapons to many troops. 
I forget which but they used Czech weapons to almost totally equip either 10 or 20 divisions. From pistols to 15cm howitzers. Mucking about too much with basic weapons in the late 30s could mean several divisions sitting around waiting for weapons.


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## davebender (Nov 8, 2014)

It's pointless to speak of medium tanks, StuGs, 7.5cm AT guns, 81mm mortars etc. without first building the military industrial infrastructure necessary for efficient mass production of such weapons.


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## tomo pauk (Nov 8, 2014)

Shortround6 said:


> ...
> But in actual practice?
> and 120mm mortar ammo _can_ weigh 45kg for two rounds in a wooden crate. Not including fuses or propelling charges.
> http://mirex-ds.com/products/ammunition/Ammunition Mortar Round 120mm High Explosive.pdf
> ...



The 120 mm sorely needs at least horse teams to function properly.



> Germans might have shifted to dual 20mm AA guns a lot sooner, perhaps they thought the improved rate of fire of the M38 was just as good?



Hmm - seems like the 20mm Flak never received the Mine shell? If introduced, it should bolster the efficiency. BTW, I'd like to see the single 30mm installed on modified light tank chassis, like the future Marder/Wespe; should also harm an AFV, if need arose. The Matilda II and T-34 are safe, though. 


> In any case the 30mm AA guns in use at the end of the war were the MK 103 guns and not the slower firing MK 101 guns. While the MK 101 may have been better than the Flak 38 you start getting into target effect vs weight of weapon/carriage.



The RoF of the MK 101 was some 50% greater than the 3,7 Flak 36/37, the effective range being much closer to the 37mm than of 20mm. 'Regular' HE-T shell was at 440 g, vs. 640g for the 37mm - the MK 101 will throw more weight through the muzzle than the 3,7 cm Flak 36/37.
If we want to tow a gun by the lorry anyway, the 30mm makes much more sense than the 20mm. 



> One point of easy change was the 37mm AT gun, It was the first of it's generation (pretty much, first guns were issued in 1928 ) and as such had the poorest performance. As such it _should_ have been replace the soonest. Russians stuck a 45mm barrel on the same carriage in 1937 and got roughly the same performance using standard ammo as the Pak 37 got with tungsten cored ammo. HE performance was better too
> The story of the 37mm being kept for the MK III tank but with a larger turret ring is well known.



How much point there is in having two 5cm cartridges anyway? Perhaps go for something in between, but with only L60 barrel from the get go, both for the tanks and AT? 



> Germans do have the same problem as many other countries. The very rapid increase in the _size_ of the armies made it very hard to change weapons as interruptions in production meant delays in issuing weapons to many troops.
> I forget which but they used Czech weapons to almost totally equip either 10 or 20 divisions. From pistols to 15cm howitzers. Mucking about too much with basic weapons in the late 30s could mean several divisions sitting around waiting for weapons.



+1 on that. 
It would be interesting to know how much the captured Polish gear contributed, even though it was less modern than Czech gear.


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## davebender (Nov 8, 2014)

German 10.5cm howitzer sabot shell. Sub caliber projectile consisted of standard 8.8cm Pzgr39 AP shell. Unlike most APCR and sabot rounds this ammunition does not require scarce tungsten for core.

Performance when fired from standard 10.5cm leFH18M howitzer.
765 meters per second. 80mm armor penetration @ 1,000 meters.
.....Performance far superior to T-34 and Sherman tank main guns. 

Get this sabot shell into mass production during 1941 and Germany can forgo introduction of 7.5cm/48 tank / AT gun. Instead every German light howitzer can perform double duty as AT gun provided they are equipped with proper sights.


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## tomo pauk (Nov 8, 2014)

At under 800 m/s, it certainly does not need the tungsten to prevent it from shattering. The 'PzGr.40' version, featuring the projectile from the 88mm that is within a suitable case to make up to 105mm would still be a problem for all Allied tanks under 40 tons.
Problem for the tanks AFV is that they would be short on cartridge numbers, though - the 105mm ammo took much more space than 75mm ammo.

Hmm, maybe going for a 'straight neck' 88mm ammo gun for the 20+ ton AFVs? The AP capabilities on par with 7,5cm PaK, HE as good as Tiger (but at lower MV)?

edit - actually, the 88mmL56 ammo was already 'straight-necked'; the casings for the AFV should be around 500mm long (vs. 495 for the 'medium' 7,5 cm, and 571mm for the Tiger's gun), and about as wide at the rim as the 'medium' 7,5 cm.


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## davebender (Nov 8, 2014)

Sd.Kfz.11 was the proper towing tractor for German 10.5cm light howitzer. How many rounds of ammunition did it carry in addition to 8 soldiers and towing the weapon?


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## tomo pauk (Nov 9, 2014)

Not sure about the number of rounds carried.

What about the tanks?


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## tomo pauk (Nov 9, 2014)

Until we arrive to the mighty (and the ones that are not) panzers, here is the handbook for the German ammo. Covers basically all, from 37mm Pak to 305mm Czech mortar.

DepositFiles


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## davebender (Nov 9, 2014)

The relatively small StuH 42 (i.e. StuG IIIG armed with 10.5cm howitzer) carried 36 rounds of ammunition inside the hull. 

7.5cm HE shells typically contained about .7kg of HE filler.
German 10.5cm HE shell for leFH18M howitzer introduced during 1941 contained 2.1kg of HE filler.

Armored vehicles typically fire more HE then AP. That's what makes leFH18M howitzer plus 10.5cm Pzgr39 TS shell look so attractive. leFH18M howitzer HE three times as powerful as PaK40 cannon and 10.5cm sabot round perfectly capable of defeating WWII era armored vehicles. leFH18M howitzer was also relatively reliable (10,000 round barrel life) and inexpensive to mass produce.


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## Shortround6 (Nov 9, 2014)

" leFH18M howitzer was also relatively reliable (10,000 round barrel life) and inexpensive to mass produce"

The Barrel life has darn little to do with being "reliable" and a lot more to do with being "durable", they are NOT the same thing. 

Barrel wear is very often proportional to the heat value of the firing charge (temperature and total heat released) and the size of the bore ( more sq in to dissipate the the heat). 

I would like very much to know _why_ the leFH18M howitzer would be so much cheaper to mass produce than a 75mm AT gun? 

The *FACT* that the howitzer would be harder to hit with doesn't seem to enter into these calculations though. 

Neither does the *FACT* that the German Pak 75 used a propelling charge about 28% the weight of the propelling charge in the Full AP round with a corresponding reduction in barrel wear. 

Howitzers often did NOT fire the full charge so their barrel life has to be figured accordingly. Rate fire has something to do with it too, Not so much a problem with AFV guns but some 105 Howitzers used up their barrels in about 1/2 the time if used for intensive bombardments at high rates of fire.


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## tomo pauk (Nov 9, 2014)

> The FACT that the howitzer would be harder to hit with doesn't seem to enter into these calculations though.
> 
> Neither does the FACT that the German Pak 75 used a propelling charge about 28% the weight of the propelling charge in the Full AP round with a corresponding reduction in barrel wear.



I'm not sure that I completely understand those two sentences.


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## Shortround6 (Nov 9, 2014)

Mr Bender seems to think that using the 105 howitzer as tank (or gun to arm Stugs) with and using "trick" ammo would be a better solution than what was used historically. 

The 7.5 PaK gun has a point blank range of about 870 meters firing stand AP ammo. The 10.5cm howitzer will have a point blank range no better than that using the "trick" ammo and much more likely than not will have greater dispersion. 
Early APDS rounds had a fair amount of trouble with dispersion (getting the sabot to fall away cleanly). 

He also touted the 10,000 round barrel life of the 10.5 cm Howitzer. The 7.5cm Pak had a rather variable barrel life depending on what ammo you firing through it. Regular AP with a 2.75kg propelling charge or the HE with a 780 gram propelling charge. Obviously they do NOT wear the barrel the same. The Pzgr 40 round used a propelling charge of 3.80KG. 

The 10.5cm Howitzer used propelling charges anywhere from 180 grams (Charge 1, MV 200m/s, max range 3575m) to 595g (charge 5, MV 391m/s, max range 9150 meters) Charge 5 was the charge used with the _conventional_ AP round and the early hollow charge rounds although MV would be different. There was a Charge 6 of 984 grams (470m/s, max range 10,675m) that was used with some of the later hollow charge rounds. 
Once again the barrel wear would be rather different from the bottom to the top charges. BTW the supercharge that got the German 10.5cm how to 12,325m was1.77kg. Granted not all the powders were the same formulation.


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## tomo pauk (Nov 10, 2014)

Okay, now I understand what you've saying a post earlier.

The 10,5cm howitzer has an advantage vs the 7,5cm 'full power' guns that it was available way before the Matilda II or Char B were encountered, let alone the T-34s. The Germans howitzers, along with 8,8s, were instrumental in order to halt the Allied (British, mostly) counterattack at Arrass in 1940. The Vespes, but in 1941, might be well able to kill T-34s, provided they have decent AP ammo. 

BTW, the Germans used a great number of different 7,5 ammo, just for their own guns - for IG (same for Pz-IVC/D?), for 'brazilian' guns (also used by Germans?; same also for the leFk 16NA?), for 7,5cm Pak, for 7,5cm Kwk 40, for the Panther. A little forethought could be useful here.

That begs a question - perhaps go with the leFk 16NA ammo accompanying gun* for the Pz-IV from day one? The capabilities were at the ballpark with the French/US 75mm.

added: a new gun, of course


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## Shortround6 (Nov 10, 2014)

While the 10.5 How was available earlier it was a much bigger gun and might have trouble fitting into a MK IV turret. 

Without "trick" ammo it has a couple of problems compared to the tank guns of the time.

One is rate of fire and the other is low velocity which equals short effective range. Short in the sense of _hitting_ the target with the first or second round (which goes back to rate of fire). The "standard" AP ammo for the 10.5 had a MV of 390-395ms compared to the 7.5cm KwK37's 385 m/s so there was little practical difference in trajectory until you get to long ranges. The 3.7cm had a MV of 745m/s and the short 5cm had a MV of 685 m/s making them easier to hit with. 

Granted bouncing 2-4 rounds of 3.7cm off the enemy instead of taking him out with one hit is a bit discouraging 

The 7.5KwK 37 used a muvh longer cartridge case than the Infantry gun. 

according to Tony Williams table. 75-77 MM CALIBRE CARTRIDGES the Germans used at _least_ 12 different 75 mm rounds not including the 1891 left overs and assorted 77mm leftovers OR assorted captured guns (French 75 counted in with the 12 already), so _some_ forethought might have helped. Having different ammo sometimes prevents mistakes though. Using different propelling charges in the same case for different guns might lead to even more confusion and accidents.


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## tomo pauk (Nov 10, 2014)

Shortround6 said:


> While the 10.5 How was available earlier it was a much bigger gun and might have trouble fitting into a MK IV turret.



Maybe the German abbreviations are guilty for the confusion - the leFk 16 was the 7,5 cm gun. The MV was some 660 m/s, cartridge was 75 x 200R. Funnily enough, the 'brazilian' guns, while employing a bigger casing ( 260 mm long), yet the MV was at 485 m/s?? Maybe someone mistyped the two types, or the earlier cartridge was much wider?
The gun developed around the 75 x 200R should be within the capabilities of the Pz-IV to carry it, giving enough performance vs. both hard and soft targets, while ammo count would've still be decent.



> according to Tony Williams table. 75-77 MM CALIBRE CARTRIDGES the Germans used at _least_ 12 different 75 mm rounds not including the 1891 left overs and assorted 77mm leftovers OR assorted captured guns (French 75 counted in with the 12 already), so _some_ forethought might have helped. Having different ammo sometimes prevents mistakes though. Using different propelling charges in the same case for different guns might lead to even more confusion and accidents.



Thanks for the link. 12 is really a great number, though the 75mm/3in was very popular caliber pre ww2.
Anyway - I'd cancel the 75 x 243R (for early Pz-IVs) in favor of a 'mid power' 75mm, akin to the French 75. 
Next - no bigger 75mm, but 'low/mid power' 88mm, 'straight neck', like I've proposed earlier; say, 88 x 500R - produced in lieu of 75 x 714R (Pak 40) and 75 x 495R (for tanks) ammo. That one for up-gunning the Pz-IV, Stug-III, Marders, as a towed ATG.
No monster 75 x 640R (for Panther), the 88mm (for Flak 18 and Tiger) will do.


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## tomo pauk (Nov 10, 2014)

The turret containing the 10,5 cm howitzer was actually tested on the Pz-IV, two turrets were capable of 360 deg rotation, the 3rd one 70 deg on each side. link
Unless used as a 'proper' artillery, the armor was too thin, so the Wespe was a more sensible choice. The desire to mount and dismount the turret does not make a lot of sense from today's perspective, either.


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## Denniss (Nov 10, 2014)

German tank guns used electric priming whereas towed guns or those used in SP mounts were percussion primed. The 75mm PaK 40 had to be modified to fit into the Pz IV turret (and into StuGs) so that alone created two additional ammo variants.
They had very good reasons to rebore captured guns to accept german rounds so avoiding just another logistic nightmare by adding more ammo types to shuffle around. Known examples were 76mm F-22/ZiS-3 guns to 75mm PaK 40 rounds + 76/85mm Flak to 88mm Flak 18/36 rounds


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## davebender (Nov 10, 2014)

Sd.Kfz.165/1 10.5cm leFH 18/1(Sf) auf Geschutzwagen IVb


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## tomo pauk (Nov 10, 2014)

I agree that re-boring the foreign guns was a good thing. 
The ammo for the Pak 40 and Kwk 40 differed considerably, not just by the priming. The tank ammo casing was considerably shorter and wider than of the Pak, see the picture. Stug-IIIF carried the Pak 40, the Pz-IVG was with the Kwk 40, so was the PzJgd 38(t).
Why they bothered with the new ammo type for the early Pz-IV (A-F) is a tough question, with already a half a dozen of available ammo types of similar power.


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## Shortround6 (Nov 10, 2014)

davebender said:


> Sd.Kfz.165/1 10.5cm leFH 18/1(Sf) auf Geschutzwagen IVb
> View attachment 276432



Lets see, most of this turret has no roof. Which means no commanders cupola. 
14.5mm armor is hardly what you want to go into battle with after about Sept of 1939. 

can you please post a photo showing the co-axial machine gun as I am having a hard time finding it these photos. 

Radio was receive only, no transmit. 

What a great concept for a tank.


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## tomo pauk (Nov 11, 2014)

If I've got this right, here are weights of propelling charges (maximum, with initial charge where present) for the 7,5cm guns used by the Germans in ww2:

- le. I.G./le. Geb.I.G. (light infanty gun/light mountain infantry gun) - 71,5 g
- Kw.K. 37 (for eg. Pz-IVA until -F) - 410 g
- le. F.K 18 - 589 g
- PaK. 97/38 (Polish French 75 at 5 cm Pak carriage) - 750 g (French ammo), 805 g (Polish ammo)
- le. F.K. 38 ('brazilian' gun, also in German service) - 1110 g 
- Kw.K 40 (eg. for Pz-IVG) - 2450 g
- PaK. 40 (towed, also on StuG-IIIF/G*) - 2770 g (similar for the re-bored Soviet F-22 gun)

Didn't come across the data for the Panther's gun, though.

*my mistake, the Pak 40 was not used on Stug-III.


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## Denniss (Nov 11, 2014)

StuGs used the StuK 40 which is a modified KwK 40, not the PaK 40.


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## tomo pauk (Nov 11, 2014)

Indeed youre right, I'll edit the post accordingly.


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## Denniss (Nov 12, 2014)

I assume the JPz 38 and IV also used a L/48 KwK derivative, not a L/46 derivative. Although I don't know if they were electrically or percussion primed.


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## tomo pauk (Nov 12, 2014)

Agreed on that. The shorter ammo could mean a lot for manhandling in the confines of the AFV, too, for almost no loss in AP capabilities.


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## wiking85 (Nov 15, 2014)

Well if I had my druthers and we are only talking about the army, then I'd say only produce the Pz IV chassis with the L40,8 75mm gun. No Pz III except as an experimental model to test out torsion bar suspension. After that I'd avoid the Tiger and Panther and produce only the VK3001 with L70 main gun and work on increasing mobility and reliability like the Leopard 1. Perhaps the VK3601 could be produced eventually as an upgrade to the Vk3001 with the 88mm gun and greater upgradability. I'd place mobility over reliability and only start producing the VK series in 1942 when they are ready. I'm not going to mess around with much sloped armor, just something like the US T-20 series or the Pz III/IV:




https://en.wikipedia.org/wiki/T20_Medium_Tank

Honestly though armor protection should be the last thought in tank design for the Germans at this point, as combat experience demonstrated that mobility and hitting power were far more important:
https://de.wikipedia.org/wiki/Leopard_1#Entstehungsgeschichte


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## tomo pauk (Nov 15, 2014)

Here is my take on the 5-10,5 cm cannons for tank/AFV and anti-tank usage, direct fire as a main task:
- 5cm gun, preferably using the more powerful cartridge from the two. The HE shell need to be longer, heavier. Need to be ready for 1939.
- 7,5 cm gun, using the cartridge from the F.K. 38 gun, as a tank gun, barrel lengths 30-40 caliber. Also for 1939
- 8,8cm, using the ammo historically used the Tiger tank and Flak guns, barrel L/56. Need to be ready for early 1941.
- 8,8 cm, casing narrower than the Tiger's round had, casing length circa 500 mm, propellant charge of 2.5-2.8 kg (comparing vs. the Pak 40 at ~2,8 and KwK 40 at ~2,5 kg), both as AFV and anti-tank gun, barrel L/40, MV at circa 700 m/s for full bore (9kg shell). Also for early 1941.
- gun for 10,5cm x 822mm R, the historical ammo for Tiger II necked out to accept bigger shell. For late 1942/early 1943.

Not sure whether is a good idea to have anything bigger than the small 8,8cm as a towed ATG. The bigger ones need a vehicle to be installed on, tracked preferably, to act as self propelled ATGs.


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## davebender (Nov 15, 2014)

Original Panzer IV chassis was rated at 18 tons due to miserly steel allocation for German tank program. Upgraded to 23 tons during 1942 to meet emergency need for a medium tank. If we start serious planning during 1936 then we can do better.

Step 1. 
Construction of three 300 vehicle per month armored vehicle plants begin immediately at Alkett, MIAG and MAN plus plants for component suppliers (engines, turrets, weapons etc.). Without these factory complexes any tanks we design are just artist renditions.

Step 2.
1936 Germany had no armored fighting vehicles worthy of the name (panzer I doesn't count). We need something immediately. I propose a light tank / full track weapons carrier made from existing components to largely eliminate development time.
.....Suspension and engine copied directly from Sd.Kfz.7 artillery tractor which is already in production.
.....Light tank variant identical in size to historical Panzer IIL. 4.63m long x 2.48m wide. 30mm frontal armor.
.....Weapons carrier variant gets same 220mm chassis extension as historical Wespe. SP 10.5cm howitzer and SP sIG33 15cm rifled mortar use this chassis.
.....Light StuG variant hull similar to historical Hetzer. However vehicle uses Wespe chassis (220mm extension, engine moved to center). 50mm well sloped frontal armor. 7.5cm/43 main gun.
.....SP Flakvierling can use light tank chassis but with 1,900mm turret ring. Vehicle is plenty wide.
These inexpensive (about RM 40,000 each) vehicles get produced like hot rolls. Light tank production ends when larger medium tank enters service. However SP artillery remain in production indefinitely.

Step 3. Design a proper 30 ton medium tank powered by 400 hp Daimler-Benz diesel engine.
Essentially a larger version of Panzer IIL. 
Designing and testing a vehicle this large takes time. But we've got breathing room as Panzer II / light StuG can hold the line until 1941. When design is ready one of the 300 vehicle per month factory complexes will be devoted entirely to this tank. A second factory complex will be devoted entirely to a matching 30 ton StuG. Third factory complex will keep producing Panzer II based SP artillery.


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## tomo pauk (Nov 15, 2014)

More German manuals, including the ones for ammo:
Germany old
Some interesting articles about (not just German) AFVs:
History | For the Record

BTW, seems like Tiger's ammo propellant was at 2,9 kg max, the Panthers at 4 kg, going by those manuals.


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## Shortround6 (Nov 16, 2014)

davebender said:


> Original Panzer IV chassis was rated at 18 tons due to miserly steel allocation for German tank program. Upgraded to 23 tons during 1942 to meet emergency need for a medium tank. If we start serious planning during 1936 then we can do better.
> 
> Step 1................. Third factory complex will keep producing Panzer II based SP artillery.




Let me see if I have this right. Do away with ALL the tanks that did the majority of the _effective_ fighting in 1939-40 and replace them with SP guns?

The MK IIs were NOT particularly effective in combat without back-up/support from the Czech tanks or Pz IIIs IVs. and NO SP guns built on a MK II like chassis are NOT a substituent for _real_ tanks in offensive operations however well they _might_ perform on defense or from ambush. 

And by the way, the MK IV hit 22.3 tons in April of 1941 with introduction of the F model with the short gun. The MK IV hand't weighed 18 tons since the first 35 built in late 1937 and early 38. The weight limit had as much to do with the capacity of the European bridges and the German army's portable bridges as it did steel allocation.


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## davebender (Nov 16, 2014)

Czech tanks have nothing to do with German planning during 1936.

Bear in mind we are building the 2.5m wide Panzer IIL, not 2.28m wide Panzer IIC. In a pinch vehicle can be armed with 5cm/60 main gun just as was planned for historical Panzer IIL. I suspect 7.5cm/24 cannon would also work.


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## Shortround6 (Nov 16, 2014)

They didn't have anything to do with German planning in 1936 but they sure filled the gap with the lack of MK III tanks didn't they? 
Their contribution to the fighting was out of proportion to their numbers. The MK IIs performed a bit poorly. 

As for the _SUPER_ MK IIL, Great idea as long as the ammo holds out. Bang!, oops, have to go back and reload. 

Ammo for the MK IIL 330 rounds of 20mm and 2250 rounds of 7.9mm. Ammo for the Big diesel powered 8 wheel armored cars, 480 rounds of 20mm and 2400 rounds of 7.9mm. Ammo for the big diesel powered 8 wheel armored cars with 50mm guns??? 55 rounds of 50mm and 1050 rounds of 7.9mm. 30-37 rounds of 50mm ammo for the super MK II? MK IIIs could carry 84-92 rounds and a _lot_ more MG ammo. 

Small chassis with big gun may not always be the best choice. 

BTW the MK III was under _design_ in 1935 and the first 5 were completed by early May 1937. Now maybe the Germans could have pushed harder but they went through several suspension designs (and not all the eight wheel MK IIIs used the same spring set-ups), two engines, a couple of transmissions (changed again on the "H") and the steering system.

Of course with your planning the _SUPER_ MK II will have a perfect engine, suspension, transmission and steering gear from day one? 

First MK IIs used a 5.7 liter 130hp engine, most of the rest used a 6.2 liter 150hp engine, the "L" used a 6.75 liter 180hp engine (and 200 more rpm) . The Pz 38(t) used a 7.75 liter engine that went though 125, 140 and 160hp versions by increasing the rpm among other things.


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## davebender (Nov 17, 2014)

m. Zgkw. 8t KM m 8





If it uses same suspension and drive train as Sd.Kfz.7 artillery tractor it will have an adequate engine, suspension, transmission and steering gear from 1934 onward just like vehicle in above picture. And it will automatically benefit from ongoing Sd.Kfz.7 improvements in those components.


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## Shortround6 (Nov 17, 2014)

Do you even read your own sources? That half-track used the same engines as the regular Panzer II. It just started with a bit smaller version and stopped before it got to the 180hp version used in the L.
Your perfect engine might be a bit under powered for an up armored, up gunned, stretched chassis tank.

BTW, still waiting for picture of MK IV turret with 105mms gun, co-ax mg, closed top and commanders cupola.


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## tomo pauk (Nov 17, 2014)

Although the development of the Flak artillery was the domain of the Luftwaffe, we might discuss it here. Any suggestions for the development of the light and heavy Flak? How realistic is the proximity fuse, and/or guided missile for, say, early 1940s Germany? Unguided rockets? I've already suggested an earlier introduction of 30mm.


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## Shortround6 (Nov 17, 2014)

I think you can pretty much forget anything electronic. Germans were working at a pretty fast pace there to begin with and the problem wasn't the idea but the hardware.
It also took the allies a number of years after the war to turn some of the German prototypes into weapons suitable for service.
You might look to the British for their success, or lack of it, with AA rockets in the early part of the war. You also hit the problem with rockets that each rocket is cheap but you need a lot of them and they use a lot more propellant per round than the expensive gun. Figuring where the crossover point is, is the trick.
Early introduction of the 30mms might be best bet.


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## wiking85 (Nov 17, 2014)

Shortround6 said:


> I think you can pretty much forget anything electronic. Germans were working at a pretty fast pace there to begin with and the problem wasn't the idea but the hardware.
> It also took the allies a number of years after the war to turn some of the German prototypes into weapons suitable for service.
> You might look to the British for their success, or lack of it, with AA rockets in the early part of the war. You also hit the problem with rockets that each rocket is cheap but you need a lot of them and they use a lot more propellant per round than the expensive gun. Figuring where the crossover point is, is the trick.
> Early introduction of the 30mms might be best bet.


German Research in World War II by Leslie E. Simon, Major General, Ordnance Department, U.S. Army, Retired, former Director, the Ballistic Research Laboratories. Merriam Press Military Digital Library L99
This 1947 survey indicates that like other fields the German electronics industry was under utilized in terms of research.


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## tomo pauk (Nov 18, 2014)

Shortround6 said:


> ...
> You might look to the British for their success, or lack of it, with AA rockets in the early part of the war. You also hit the problem with rockets that each rocket is cheap but you need a lot of them and they use a lot more propellant per round than the expensive gun. Figuring where the crossover point is, is the trick.



The shortcoming of the AAA, at least as what I see as such, is that, 1st, the AA gun need to have luck the enemy bombers stumble on it's firing envelope (height, range, basically a 'squashed' hemisphere) - meaning that some of the AAA will do firing one day, while the others will not fire maybe 10 days. 
2nd, once the enemy bombers are within the envelope, the AA gun will be able to fire only so many rounds before the bombers are away. 
My idea (actually not mine, but anyway) is to employ a multiple launcher, say 30-40 rockets per launcher, so a battery can expand 180-320 rockets (depending on how much launchers of how big a size the battery has) in maybe 10-15 seconds, so the short time the bombers are close can be used well.
The missile might be somewhere between 7-8 cm of diameter, 700-800 m/s high speed within a few seconds. Something like a R4M's big sister. A translation from the German Wikipedia:



> The rocket motor consisted of a chamber 375 mm in length, 45 mm internal diameter and welded to the combustion chamber of a nozzle with 13 mm clamping. It contained 875 g of a double base propellant as a powder to the base in the form of powder Diglykoldinitrat rods. After 0.8 s burn time ( about 200 m flight path ) reached the R4 / M its maximum speed of 550 m / s [ 1 ] (about 2000 km / h) .



For a warhead of, say, twice the weight to be launched 50% faster we might need some 3 kg of propellant? Vs. 2,7-2,9 for the Flak 18/36. The lower grade steel can also be used for the rocket, unlike what was needed for the AAA ammo.
I'm not sure when the Diglykoldinitrat beacame available, though.


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## Shortround6 (Nov 18, 2014)

Tomo, please see:

Z Battery - Wikipedia, the free encyclopedia

and 

https://archive.org/stream/tractors...of-Weapons-of-World-War-II#page/n173/mode/2up

Main contribution of the British AA rockets was that they provided the engines/motors for the air to ground rockets.


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## tomo pauk (Nov 18, 2014)

It does seem like the solid propellant needed to be more developed, for such missiles to work at greater distances altitudes.

The wire-guided missile might work with those? The speed of 350-500 m/s was within the capabilities of even the low-tech rocket fuel (but still fast enough for hitting the aircraft), the guidance system should be much more simple cheaper than the radio or radar guidance; no feasible jamming. The shortcoming would be the range, possibly under 4 km because of wires? It would also need a proximity fuse. Also only useful for daylight combat. Maybe to supplement/replace the 3,7cm guns?


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## wiking85 (Nov 18, 2014)

Tomo I assume you mean this weapon system:
https://en.wikipedia.org/wiki/Taifun_(rocket)

Plus all the different German SAM projects:
https://en.wikipedia.org/wiki/Category:Surface-to-air_missiles_of_Germany

Perhaps the project isn't cancelled in 1940 and renewed then in 1942. Keep it in development continuously and it should be ready by 1943-44.


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## Shortround6 (Nov 18, 2014)

It took a few years to get wire guidance to work after the war.
It took a lot longer for it to really become effective in the hands of average troops and not company demonstrators/and salesmen ( or demonstration troop units).
It took a LOT of practice to hit even tank targets on a consistent basis.
The first generation guidance systems required the operator to "fly" the missile to the target. If the missile was headed to the right and the operator input left the missile turned left on a new heading and continued in that direction until the operator input another correction to turn it back to the original heading to the target.
2nd generation systems required the operator to steer the missile back to the line of sight and then let go of the control and the system would "automatically" turn the missile to the original heading or parallel course without the operator.flying a bunch of (hopefully) smaller zigzag.
3rd generation simply required the operator to keep the target in the sight, electronics took care of the rest.
They are all wire guided, but only the first has chance of working in WW II and the actual hit rate is a lot less than many people think.


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## tomo pauk (Nov 18, 2014)

The Ruhrstahl X-4 worked prior ww2 ended, air-to-air missile. The anti tank sibling, the 'Rotkapchen', also worked, though I'm right now more interested in the anti-aircraft application of a missile with wire guidance. It would me the M-CLOS guidance, of course.


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## Shortround6 (Nov 18, 2014)

The systems "worked" but accuracy in the field varied from a high of about 25% with skilled operators to a low of 2% with unskilled operators under suppressive fire.
This for anti-tank work and some of the missiles had an automatic height finder and the operator only controlled left and right or height correction is minimal.
For use against aircraft throw in the vertical element.
They may "work", is the cost per aircraft destroyed (cost/benefit) worth it compared to conventional weapons at that point in time.
Prototypes and patents for printed circuit boards date back to 1903 but the first real production was by the U.S. in 1943 for proximity fuses. The U.S. released the circuit board for commercial use in 1948 but it didn't become common in consumer electronics until the late 50's.
You don't need printed circuit boards to make prototypes or even production missiles but they make them much cheaper and easier to make.
Just one of the things between an idea or prototype weapon and a mass produced one.


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## tomo pauk (Nov 18, 2014)

The 'dumb', wire guided missiles don't need much of electronics to start with. The cost of both AA guns and their ammo also need to be factored in, so we can compare. 
The operator of the AA missile does not need in the same time to fly an airplane.

The AA MGs on the tanks and AFV - bad, or good, or give them MG 131s?


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## Shortround6 (Nov 19, 2014)

The wire guided AA missile might very well have done a good job compared to conventional AA guns, however it is not quite as easy or quick to develop as some people think nor is it an "automatic" kill. Perhaps even a 5% hit rate would have been an improvement costwise over conventional guns/ammunition. 
However even " don't need much of electronics to start with" has to be taken in context. MK I tanks and stugs weren't equipped with radio transmitters. Many tanks that had transmitters were limited to 2-4KM range when using voice, further if using code (one reason for a radio operator) so "electronics" themselves weren't much to start with compared to what they were even in the 1950s. What you can build in the lab/workshop (dozen a week/month?) vs what you can build at the rate of several hundred per month (or a thousand a month) are often several years apart. 

The MG 131 as an AA gun has a bunch of plus and minuses. 
The American .50 cal had a similar rate of fire to the American .30 cal but a much better "long range" performance, meaning less lead was needed. (and BTW the rounds fired for the .50 in the AA role per plane brought down were astronomically high). 
The MG 131 has a much higher rate of fire but a much poorer down range performance (more lead needed) but the German 7.9mm MGs also had a _much_ higher rate of fire than the American .30 cal. 1 1/2 to 2 times higher making them better AA guns to begin with. Rate of fire for the MG 131 and the MG 34 were pretty close. 
To "kill" attacking aircraft with either 7.9mm/.30 or 12.7-13mm/.50 cal AA guns pretty much requires the "golden BB". One _lucky/critical_ hit out of thousands of rounds fired. 
_However_, *successful* AA defense doesn't mean planes killed, it meant planes driven off to bomb something else or forced to bomb/shoot from further away so that the aircraft's weapons are much less effective. A very hard thing to measure or "post" on a scoreboard but very real none the less. 
Are 13mm tracers going to be that much more effective than 7.9mm tracers going by the cockpit? Are 13mm holes (a few holes) appearing in the wings going to that much more frighting than 7.9mm holes? 
The Early German tanks weren't carrying a lot of MG ammo to begin with. A MK IV carried about 1/2 the rifle caliber ammo of a Sherman and _then_ the Sherman added 300-600 round of .50 cal. 

The MG 131 might have had a place as an AA weapon but sticking them on large numbers of AFVs like the Americans did probably wasn't the best use.

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## Shortround6 (Nov 20, 2014)

To expand on the Previous post a bit. The German MG 131 was pretty good at what it was designed for. To be a higher powered replacement for the MG 17 aircraft gun. It had to fit into most spaces the the MG 17 did and not change the weight that much. 
In this it was a success. However it also meant that the MG 131 used the _least_ powerful 12.7-13.2mm round used in WW II. It's muzzle energy was about 9600 joules compared to the British, Italian, Japanese 12.7mm/0.5in 10,600 joules, The American .50 cal 17,800 joules, the Russian 12.7 x 108 rounds 19,200 joules. 
For anti-aircraft work the combination of light bullet and low velocity (compared to the American and Russian guns) really limit it's effective range even if better than the 7.9mm.

I would also note that from the 1950s through to today, many European countries (including the British) continue to use 7.62mgs for AA guns on tanks even though at times (the 1950s ? ) they could have all the .50 cal guns they wanted under NATO programs. 
Different doctrine?


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## tomo pauk (Nov 20, 2014)

Two of the late-war German AFVs that I kinda like. 
1st, the Ardelt Waffenträger, the tracked vehicle conceived to carry either 10,5cm howitzer, 15 cm howitzer, or the 8,8 cm Pak. The vehicle itself was using the components of the Pz 38(t) tank as much as possible, the Germans planned to switch to the Pz 38(d) as a base vehicle. The 'd' stands for 'deutsch' - German. In this 'iteration', a similar vehicle would carry the 8,8 cm L/56 AFV gun, along with the howitzers. The captured Polish AA gun, 7,5cm L/50 'Star' would also be very useful, if 'only' for AT work.
The ammo trailer, or ammo vehicle for howitzers is a must.







Another AFV is the quadruple 30mm that used the Wirbelwind as the base, the 'Zerstorer'. Problem with that is that several things are lacking, to allow for a reasonable early introduction - the 1st versions would involve the MK 101 cannon (lower RoF, both cyclic and practical; production not sufficient for many multiple mounts to be issued), while the tank chassis of 20-30 tons would be regarded as too a precious to be used for Flak duties. So the best bet would be a twin 30mm on something like the Wespe or similar chassis, like the Pz 38(t) or the Ardelt. The Pz 38 mounted a single 20mm Flak, too much of an AFV for too little Flak IMO.


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## Shortround6 (Nov 21, 2014)

I am not a big fan of big guns on little chassis. They are often not as "cheap" as they first appear and also sometimes have some severe limitations in combat. as an example we have the Italian Semoventi da 90/53 

















Model




The Ammo carrier





If you are in the middle of a war and are in a real bind in getting/moving AT guns it may be one thing. To _plan_ on using such weapons several years _before_ you go to war is another thing entirely. 

Adding a second tracked chassis and a trailer in order to carry crew and reasonable amount of ammo is rather an admission that that the basic vehicle isn't quite up to the job. Not such a big deal with 149-155mm corp level guns but for AT work?


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## tomo pauk (Nov 21, 2014)

I'm not trying to sell such the weapon as the replacement for a proper tank. Rather, they would be a replacement for a towed heavy ATG. The vehicle can tow it's own trailer, maybe along with another 1-2 crew members.


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## Shortround6 (Nov 21, 2014)

towing it's own trailer calls for a more powerful engine (BTW the prototype in your picture used the same 220HP diesel engine used the later 8 wheeled armored cars). Large 88-90mm AT guns are not needed in 1939-42. 

If you are planning weapons in 1936-38 for use in 1943-45 you would be better off planning on how to get to South American with large amounts of gold  

If you are planning in 1936-38 for weapons to be used in 1939-42 that is something else but has to use engines/weapons/technology that will be available in _production_ form in 1939-42. 

The Heer didn't really _need_ better AA guns in 1939-42 although they would have been _nice_. The Luftwaffe managed to keep the enemy aircraft of the Heer's back for the most part. From late 1942 on things got worse and worse. 
For the attack on France in 1940, more AA guns or more ???? French and British tactical air didn't manage much more than show they could die bravely. 

The 30mm MK 101 was feed at first from 6 or 10 round box magazines, later 30 round drums. Not so bad in the open but a pain in a confined turret. Practical rate of fire isn't going to be much better than the 3.7cm Flak 37. The 3.7cm was supposed to cycle at 160rpm and you could drop extra 6round "clips" onto the feed way (some of the guns apparently had longer feed ways than others) as the gun used the first one (much like dropping extra 4 round "clips" into the top of a "Bofors" gun, rather than have to remove the existing magazine (box or drum) before you could fit the new one. A single loader wasn't going to keep up with the gun in continuous fire but you might get 12 to 18 rounds in one long burst. 
Germans had a fair number of 20mm and 37mm guns mounted on trucks and half tracks so until the ground got really bad the full tracked chassis wasn't really needed.


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## parsifal (Nov 21, 2014)

This kinda discussion rapidly gets out of hand as people confer superhuman powers of perfect hindsight to rectify obvious errors of the historical situation. The German Army with a long barrelled 75mm gun is about as likely as me getting a date with claudia schiffer. Okay im male and shes female, and we are both heterosexual. From that point on, the prospect gets ridiculous, and i see the ra ra boys are at it again when it comes to the German army.

The second thing is resources. Redesigning the army does not mean give it more resources. bigger and meaner equipment is usually more expensive, and money is one thing the Germans dont have in 1936.

So what would be my priority. Number 1, scrap all the fripperies like halftracks and heavy tanks. You can build 4 or 5 2 x 4 trucks for every halftrack, and its numbers that count. Number 2, implement the rationalization plan for MT from 1936 instead of 1939. Its the obvious thing to do and could have been done in 1936. 3 standardize on one calibre of field artillery to simply logistics.

Integrate the Panzer Divs by making them less top heavy with armour and forming proper combat teams CCA and CCB to maximise flexibility but avoid the US mistake of destroying esprit in the units 

Revisit tank production. Something was radically wrong in Germany....when they only produce about the same number of tanks as the British. Perhaps start to look at a shadow factory system, or subcontracts for components. Look at the basic types and make sure they are as simple as can be made, doing away with ALL the fripperies that bedevilled the German efforts at tank production for most of the war.


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## tomo pauk (Nov 21, 2014)

Shortround6 said:


> towing it's own trailer calls for a more powerful engine (BTW the prototype in your picture used the same 220HP diesel engine used the later 8 wheeled armored cars). Large 88-90mm AT guns are not needed in 1939-42.
> 
> If you are planning weapons in 1936-38 for use in 1943-45 you would be better off planning on how to get to South American with large amounts of gold
> 
> If you are planning in 1936-38 for weapons to be used in 1939-42 that is something else but has to use engines/weapons/technology that will be available in _production_ form in 1939-42.



I've proposed the 'non-Flak' 8,8 cm gun to be produced/introduced somewhat earlier than it was the case historically, ie. introduction some time in second half of 1941, instead of late 1942. The 'driver' for that might be the knowledge of the French heavy tanks in service.
The Germans sporadically used the 8,8 in the AT role already during the SCW, and they fielded the it on a half-track, admittedly intended/conceived as a weapon to hit fortifications, in 1940.
The 8,8cm L/56 AFV gun was lighter than the 8,8cm Pak, even when we discount the weight of the carriage. The engine can start from it's historical level, upgraded when possible. The chassis - Pz 38(t) with engine in the middle, as with the Ardelt W-t.
The 88 mm guns were certainly useful to battle the French heavies, Matilda II, T-34 and KV tanks, that occurred many times before 1941 ended.



> The Heer didn't really _need_ better AA guns in 1939-42 although they would have been _nice_. The Luftwaffe managed to keep the enemy aircraft of the Heer's back for the most part. From late 1942 on things got worse and worse.
> For the attack on France in 1940, more AA guns or more ???? French and British tactical air didn't manage much more than show they could die bravely.



Less AA guns? Frees a lots of manpower, the manufacturing capability can produce more artillery?



> The 30mm MK 101 was feed at first from 6 or 10 round box magazines, later 30 round drums. Not so bad in the open but a pain in a confined turret. Practical rate of fire isn't going to be much better than the 3.7cm Flak 37. The 3.7cm was supposed to cycle at 160rpm and you could drop extra 6round "clips" onto the feed way (some of the guns apparently had longer feed ways than others) as the gun used the first one (much like dropping extra 4 round "clips" into the top of a "Bofors" gun, rather than have to remove the existing magazine (box or drum) before you could fit the new one. A single loader wasn't going to keep up with the gun in continuous fire but you might get 12 to 18 rounds in one long burst.



I was trying to picture the 30mm more as a replacement for 20mm, rather than for 37mm. It does not compare bad vs. the 37mm, though.



> Germans had a fair number of 20mm and 37mm guns mounted on trucks and half tracks so until the ground got really bad the full tracked chassis wasn't really needed.



We know that the Pz-IV was a base for like 5 different AA self propelled guns (despite the urgent need for as many tanks as possible), plus the half-arsed FlakPz 38(t) with a single 20mm. There were also proposals for the Panter-based AAA, 2 barreled 37mm and 50mm.
The need for the AA to be close to the tanks all the time was certainly felt.


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## Shortround6 (Nov 21, 2014)

There are darn few heavy tanks before 1942. 

maybe 6 of these or a few more including prototypes? 






4X2 trucks work for crap unless you have really good roads. Not a guarantee in Western Europe let alone eastern Europe (and that is before you hit the Russian border.) 
So you need 4X4s or 6X6s. 4x6 often don't make it. And to really last they have to be over-built. The American 2 1/2 ton truck was rated at 2 1/2 tons payload _cross country or "off highway"._ On Highway it was rated at a 10,000lb payload. It was also rated to pull a 7,500lb trailer/load on highway and 4,500lbs off highway. 
An International Harvester K7 (commercial) 1941 2 1/2 ton 4X2 was rated at 5,000lbs on high way and 7,000lb off highway. A big difference was the IH had a 5 speed gear box while the standard military 2 1/2 tonner had not only the 5 speed but a 2 speed transfer case. Net weight for the 6X6 was about 2,000lbs heavier (over 10,000lbs)
A post war Ford 1 1/2 ton 4X2 with a 100hp V-8 weighed net 5885lbs and was rated for 3,000lbs off highway and 6,615lbs on high way. Is it a 3 ton truck in some other armies? or a commercial 3 ton truck? 

You need a certain amount of half-tracks as gun tractors or a certain amount of full tracked gun tractors. You probably don't _need_ the variety of different models of 1/2 tracks the Germans had though. 
But then a lot of European countries tried to make up in "fripperies" what the Americans did with big engines.The standard American 1/2 tracks using engines of the size and power that the Germans used in their 5 and 8 ton 1/2 tracks. 

Getting some sort of rational production plan going sooner would have helped a lot.


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## Shortround6 (Nov 21, 2014)

tomo pauk said:


> I've proposed the 'non-Flak' 8,8 cm gun to be produced/introduced somewhat earlier than it was the case historically, ie. introduction some time in second half of 1941, instead of late 1942. The 'driver' for that might be the knowledge of the French heavy tanks in service.
> The Germans sporadically used the 8,8 in the AT role already during the SCW, and they fielded the it on a half-track, admittedly intended/conceived as a weapon to hit fortifications, in 1940.
> The 8,8cm L/56 AFV gun was lighter than the 8,8cm Pak, even when we discount the weight of the carriage. *The engine can start from it's historical level, upgraded when possible.* The chassis - Pz 38(t) with engine in the middle, as with the Ardelt W-t.
> The 88 mm guns were certainly useful to battle the French heavies, Matilda II, T-34 and KV tanks, that occurred many times before 1941 ended.



This is one of my objections to some of these "what Ifs". Before the invasion of Poland the 38(t) engine was rated at 125hp. It was uprated to 140hp in Nov 1942 for the Marders and other SP guns, none of the normal 37mm armed tanks got the 140hp engine (unless during refit/repair). It was upgraded to 160hp in the Hetzer in the spring of 1944. The 88mm/56 may be a lot lighter than the 8,8cm Pak but using the historical engine you have only 57% of the power. Going to the 140hp engine gets you to 64% of the power. 
Germans could have done themselves a lot of good (and the world a lot of harm) by shifting to the 50mm/60 a lot sooner. Some sort of long 75mm gun would have been a big help too without going to the trouble of lugging 88mm guns around. 



> Less AA guns? Frees a lots of manpower, the manufacturing capability can produce more artillery?



Not really less. The the need to change numbers/ mounts/ chassis by much doesn't really move to near the top of the list until late 1942 or early 1943. And you don't create a "branch" of the Heer overnight. You want a good AA defense in 1934/44 you need a number of men who learned their "trade" in 1940-41-42 before things get really bad. Siting, coverage patterns, camouflage, communications and other stuff aside form just loading and firing the guns. 



> I was trying to picture the 30mm more as a replacement for 20mm, rather than for 37mm. It does not compare bad vs. the 37mm, though.



It may be a replacement for the 20mm but not so much in the early years. The MK 103 was lighter and belt fed. The MK 101 weighed about 3 times what a Flak 38 did (for a bare gun) and had about 1/2 the practical rate of fire unless you had the 30 round drums. The 30mm guns you worked on used a much more powerful cartridge (about 200m/s more MV with a similar weight projectile) , only weighed about 20kg more than the MK 101 (bare gun) and had a cycle rate about twice as fast per barrel compared to the MK 101. 



> We know that the Pz-IV was a base for like 5 different AA self propelled guns (despite the urgent need for as many tanks as possible), plus the half-arsed FlakPz 38(t) with a single 20mm. There were also proposals for the Panter-based AAA, 2 barreled 37mm and 50mm.
> The need for the AA to be close to the tanks all the time was certainly felt.



And all this "stuff" came into being in 1943-44 (first FlakPz 38(t) is built in Nov 1943) so the need *was* felt, just not so much in the early years.


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## tomo pauk (Nov 21, 2014)

The Germans tried the Schell (Schnell?) program, that called for standardization in military trucks, but eventually that was abandoned. Your last sentences, of a very good post, is on the money.



> There are darn few heavy tanks before 1942.



French built 400+ of Char B tanks before collapse, the order was in excess of 1100 examples. Not a stunning number when compared with ww2 mass produced tanks, but quite an amount of steel for 1940.


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## tomo pauk (Nov 21, 2014)

Shortround6 said:


> This is one of my objections to some of these "what Ifs". Before the invasion of Poland the 38(t) engine was rated at 125hp. It was uprated to 140hp in Nov 1942 for the Marders and other SP guns, none of the normal 37mm armed tanks got the 140hp engine (unless during refit/repair). It was upgraded to 160hp in the Hetzer in the spring of 1944. The 88mm/56 may be a lot lighter than the 8,8cm Pak but using the historical engine you have only 57% of the power. Going to the 140hp engine gets you to 64% of the power.
> Germans could have done themselves a lot of good (and the world a lot of harm) by shifting to the 50mm/60 a lot sooner. Some sort of long 75mm gun would have been a big help too without going to the trouble of lugging 88mm guns around.



Thanks for the engines overview. We will need to start with the 125 HP engine, switching on more powerful ones as they became available.



> Not really less. The the need to change numbers/ mounts/ chassis by much doesn't really move to near the top of the list until late 1942 or early 1943. And you don't create a "branch" of the Heer overnight. You want a good AA defense in 1934/44 you need a number of men who learned their "trade" in 1940-41-42 before things get really bad. Siting, coverage patterns, camouflage, communications and other stuff aside form just loading and firing the guns.



On May 1st 1938, there is 2300 x 20mm, 670 x 37mm and 2000 x 88mm in Wermacht hands. By Sept 1939, it is 6700 of the 20 and 37mm (mostly 20mm, single mounts) and 2628 of 88mm (mostly) and 105mm, increased to 9817 and 3095 in June 1940 - that's 14000 Flak. The German Flak gunners sure have had on what to learn their trade, and then some  (got to extract the Westerman's tables somewhere...)



> It may be a replacement for the 20mm but not so much in the early years. The MK 103 was lighter and belt fed. The MK 101 weighed about 3 times what a Flak 38 did (for a bare gun) and had about 1/2 the practical rate of fire unless you had the 30 round drums. The 30mm guns you worked on used a much more powerful cartridge (about 200m/s more MV with a similar weight projectile) , only weighed about 20kg more than the MK 101 (bare gun) and had a cycle rate about twice as fast per barrel compared to the MK 101.



The MK 101 was lighter than the MK 103: 139 kg vs. 145 kg - bare gun; 180 kg is for the MK 101 with a full 30-rd drum.
The HE shell was 440g vs. 120g for the 2cm; there was also the M-shell of 330g available, while it seems that HE shell was not used on the MK 103? Granted, the drum is necessary, until we receive the MK 103. Quirk might be that we need about same manpower for the single 2cm as we need for the single 3cm, that has maybe 3 times the practical 'throw weight' at a maybe 50% greater distance and altitude.



> And all this "stuff" came into being in 1943-44 (first FlakPz 38(t) is built in Nov 1943) so the need *was* felt, just not so much in the early years.



I'll admit that the Germans were on the forefront when it comes down to self propelled AAA. Until the LW was bested, or at least equaled in the air, there was no much need for the AAA for the 'tactical' ground forces.


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## Shortround6 (Nov 21, 2014)

tomo pauk said:


> Thanks for the engines overview. We will need to start with the 125 HP engine, switching on more powerful ones as they became available.



That sounds good but the low powered engines may not give you the speed/mobility you want. Spending time and money on chassis that will only become acceptable performers several years down the road (without spending even more money on development) doesn't sound like a good use of resources. 





> On May 1st 1938, there is 2300 x 20mm, 670 x 37mm and 2000 x 88mm in Wermacht hands. By Sept 1939, it is 6700 of the 20 and 37mm (mostly 20mm, single mounts) and 2628 of 88mm (mostly) and 105mm, increased to 9817 and 3095 in June 1940 - that's 14000 Flak. The German Flak gunners sure have had on what to learn their trade, and then some  (got to extract the Westerman's tables somewhere...)



Thank you, The Heer seems to have had enough guns, at least for the first 3 years of the war. 



> The MK 101 was lighter than the MK 103: 139 kg vs. 145 kg - bare gun; 180 kg is for the MK 101 with a full 30-rd drum.
> The HE shell was 440g vs. 120g for the 2cm; there was also the M-shell of 330g available, while it seems that HE shell was not used on the MK 103? Granted, the drum is necessary, until we receive the MK 103. Quirk might be that we need about same manpower for the single 2cm as we need for the single 3cm, that has maybe 3 times the practical 'throw weight' at a maybe 50% greater distance and altitude.



It appears you are correct on the weights of the guns but using "throw" weight gets a bit deceptive. A British 3in 20cwt AA gun has the same "throw" weight as the MK 101 using 440 grams shells if the 3in fires 15-16 rounds a minute. Problem is _hitting_ the target (unless you can scare them away with tracer). The low rate of fire with the MK 101 means that a 300mph aircraft can move almost 33 meters between each shot fired. The 2cm Flak 38 cuts that to about 19 meters traveled. 
Once you can get the high cycle rate MK 103s the 30mm gun has just about all the advantages. But using the MK 101 is a bit iffy. 

German Army never used a twin 20mm mount during the war, Perhaps a opportunity there? 



> I'll admit that the Germans were on the forefront when it comes down to self propelled AAA. Until the LW was bested, or at least equaled in the air, there was no much need for the AAA for the 'tactical' ground forces.



There was a need, it's just that it seems to have been pretty well filled by existing equipment/scale of issue.


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## tomo pauk (Nov 21, 2014)

Shortround6 said:


> That sounds good but the low powered engines may not give you the speed/mobility you want. Spending time and money on chassis that will only become acceptable performers several years down the road (without spending even more money on development) doesn't sound like a good use of resources.



The Pz 38(t) will become quickly obsolete, even more so within the limits of this thread. The body (powerplant, suspension etc) is a decent one, so using it for a bigger gun might be good use. The max speed on 9,5 ton was 42 km/h with 125 PS The 'Waffentrager' withe the L/71 gun was supposed to weight 11,2 (per German Wikipedia) while using 100 PS engine??
The L/56 version should weight 10-10,5t?



> It appears you are correct on the weights of the guns but using "throw" weight gets a bit deceptive. A British 3in 20cwt AA gun has the same "throw" weight as the MK 101 using 440 grams shells if the 3in fires 15-16 rounds a minute. Problem is _hitting_ the target (unless you can scare them away with tracer). The low rate of fire with the MK 101 means that a 300mph aircraft can move almost 33 meters between each shot fired. The 2cm Flak 38 cuts that to about 19 meters traveled.
> Once you can get the high cycle rate MK 103s the 30mm gun has just about all the advantages. But using the MK 101 is a bit iffy.



We can recall that all 2cm Flak guns weren't of the Flak 38 variety, but the Flak 30 was in majority in the early ww2. RoF was 280 rpm vs. 230-260 rpm for the MK 101.

The targeted aircraft were almost always 'followed' when within sights, ideally the angular velocity of the barrel matching (when looking from gunner's standpoint) the angular velocity of the target. It was a thing where, say, one of 20 bursts hits an aircraft (not all the shells from a burst, of course). Not when one or two shells from each burst hits. The high rate of fire was not a cure for an ill-trained gunner, but it can help. 
Barrage fire (we all fire in a portion of the sky where the aircraft will roughly appear) was sometimes used, but the ammo consumption vs. aircraft hit was out of proportions.



> German Army never used a twin 20mm mount during the war, Perhaps a opportunity there?



Indeed. Introduction of 60-rd drum would also boost the weapon's efficiency.


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## parsifal (Nov 22, 2014)

Shortround6 said:


> > There are darn few heavy tanks before 1942.
> >
> > maybe 6 of these or a few more including prototypes?
> 
> ...


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## tomo pauk (Nov 23, 2014)

Again about the AAA, this time the heavy guns. In retrospect, was it better bet to rely on a 'hit to kill', or to employ the time fuses?


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## Shortround6 (Nov 27, 2014)

tomo pauk said:


> Again about the AAA, this time the heavy guns. In retrospect, was it better bet to rely on a 'hit to kill', or to employ the time fuses?



Hard to say without doing a very detailed mathematical analysis of the situation. Near the end of the war the the 'hit to kill' method was shown to be better but in the early years the bombers flew lower. The problems with the time fuses were the errors in setting the fuse correctly to begin with and then the error in the fuse itself. A fuse might be accurate to 2% or less of the time it was set for (expected flight time) and the shorter flight times to the lower altitudes meant the error was the same percentage of a much shorter flight time. The shells slowing down considerable with altitude. 
I have no idea were the cross-over point is/was. 
The time fuse (in theory) increase the lateral lethal distance but because of the fuse problems introduced an error along the line of flight (usually bursting too early, a late burst might result in the shell hitting the target plane). The longer the time of flight the greater this "axial" error became. 
Of course not having to set fuses might speed up the rate of fire a bit.

We are back to are you planning for 1939-41 in 1936/37 or are you planning for 1943-45?


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## tomo pauk (Nov 27, 2014)

For pre-1943 time. Was thinkering about an AA gun that is similar to the Panther's gun, obviously on a AA carriage and with neccesarry extras. 
Or, the bread butter 88 L-56, firing the HE shell 'core' wrapped in a carriage to make up to 88mm, looking sorta APCR. So instead of the 9 kg HE, firing the 5-6 kg 'HE-SV' round. The barrel wear should be increased with greater MV, though.
The Gerlich system (tappered bore) does offer a 1200 m/s speed, but barrel life was only 1000 rds for the 7,5cm pak 41, vs. 6000 rds for the 7,5cm pak 40, for example.


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## Shortround6 (Nov 27, 2014)

parsifal said:


> Shortround6 said:
> 
> 
> > I forgot your concept of a heavy tank is quite unique, In my vernacular, as well as everybody else in 1936, a mkIV is a heavy tank. thats certainly how the Heer described them. Dropping everything for MKIV option means basically that the Heer fights Poland and France with no more than 250 tanks....in other words it loses the war before it starts. Sure, move to develop the mKIV after June 1940, but thats raises the issue of "who knew they were going to win with such style"
> ...


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## Shortround6 (Nov 27, 2014)

tomo pauk said:


> For pre-1943 time. Was thinkering about an AA gun that is similar to the Panther's gun, obviously on a AA carriage and with neccesarry extras.
> Or, the bread butter 88 L-56, firing the HE shell 'core' wrapped in a carriage to make up to 88mm, looking sorta APCR. So instead of the 9 kg HE, firing the 5-6 kg 'HE-SV' round. The barrel wear should be increased with greater MV, though.
> The Gerlich system (tappered bore) does offer a 1200 m/s speed, but barrel life was only 1000 rds for the 7,5cm pak 41, vs. 6000 rds for the 7,5cm pak 40, for example.



They used 85-90mm AA guns because the bigger shells had a bigger lethal radius than the 75mm shells. The bigger shells also retained their velocity better than the 75mm if they start at the same velocity for a shorter flight time. using a higher velocity 75mm _might_ work but I don't know where the cross over point is. 
BTW some sources claim only 150 shots for the 7.5cm pak 41. Barrel was made in several sections so the the one that wore the fastest could be replaced without changing the whole barrel.


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## tomo pauk (Nov 28, 2014)

Shortround6 said:


> They used 85-90mm AA guns because the bigger shells had a bigger lethal radius than the 75mm shells.



Indeed. Though, not an issue if direct hit is desired.



> The bigger shells also retained their velocity better than the 75mm if they start at the same velocity for a shorter flight time. using a higher velocity 75mm _might_ work but I don't know where the cross over point is.



It is the 'heavier shells retained their velocity better', the 85-90mm shells being roughly 50% heavier than 75-76,2mm shells. The section density was greater for the 85-90mm shells, that being a more precise statement.
The 8,8cm 'full weight' shell was at circa 9-10 kg, fired at 800-830 m/s. The 'reduced weight' shot, like the APCR for example, weighted 7,3 kg, fired at 930 m/s. It would be interesting if we'd know the velocities for different projectiles at 2 or 3 km, though.
The Panther's gun was firing the 7,2 kg shot at 925 ms, should retain the velocity better than the APCR shot of the 8,8cm, due to less drag. The 4,75 kg APCR from the Panther was fired at 1120 m/s. Again, I don't know the velocities at 2-3 km to compare.



> BTW some sources claim only 150 shots for the 7.5cm pak 41. Barrel was made in several sections so the the one that wore the fastest could be replaced without changing the whole barrel.



I have only this (open it separately):


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