Alternative German tanks & AFVs

[tomo pauk]

Germans were worried about their vehicles' anti-tank abilities a few years before ww2 started. That prompted them to go towards the 70cal weapon of 3.7cm caliber (used the different ammo vs. the known pak or kwk), as well as the 7.5cm L40.8 (specific request was that the gun can beat the French heavies, thus that power of the gun is in the ballpark of the 7.5cm n.A. 16 gun). Neither of these guns entered the 'normal' service.
The 3.7cm was good for 900 m/s with the 710g shell/shot, while the 7.5cm was good for 650-685 m/s with the 6.8g projectile, that was penetrating 61mm at 30 deg at 700m.

Side elevation of the halftrack with that 7.5cm gun: picture.

 

[tomo pauk]

Looking at the factory output of the *real* tanks, production of the Pz-IV was really low when compared with the Pz/StuG-III. Eg. in May of 1941, only 29 of the -IVs was manufactured, while the Pz-III was manufactured in 143 copies. Even the StuG-III was being made in a better tempo, with 48 copies in May 1941.
The 3:1 production ratio of the Pz-III vs. Pz-IV was sustained during even through 1942; same was the thing about the on-hand numbers. Production of StuG-III was in the ballpark with the Pz-IV production, from 1940 to 1942.

My point - slap the darned 7.5cm on the Pz-III ASAP, and, instead of the Pz-IV as we know it, make a genuine & early effort towards a 30 ton tank.

 

[Shortround6]

The 3:1 production ratio of the Pz-III vs. Pz-IV was sustained during even through 1942; same was the thing about the on-hand numbers. Production of StuG-III was in the ballpark with the Pz-IV production, from 1940 to 1942.

That is because the numbers fitted the doctrine.
A panzer battalion was supposed to be made up of 4 companies. 3 companies of MK IIIs (the fighting tanks) and one company of MK IVs, the support company firing smoke and HE.
The StuGs, in the early versions, were assigned to artillery units supporting infantry divisions, not panzer divisions. In the Field actual practice may not have followed doctrine especially by the spring of 1942.

Now in France in 1940 proposed doctrine was a real mess in the Field because there were nowhere near the number of MK IIIs needed to fill out the tables of organization. Which led to the hundreds of MK 1 and MK II tanks being used to fill out the numbers in the medium tank companies. Also the numbers of Pz 35(t) and Pz 38(t)s used as ersatz PZ IIIs. in two divisions.
For the Germans the doctrine seemed to have worked in Poland and then in France. Given the massive shortage of Pz IIIs which would be somewhat solved with the end of 1940 and 1941 production (it wasn't) and the improved Pz IIIs ( heavier armor and the short 50mm gun). Problems started with Hitler calling for 20 panzer divisions instead of 10 which meant that the production schedule was woefully short.

A lot of books/internet articles do not help as the Pz IV is often described as an infantry support tank with it's short barreled gun. It was not designed or deployed to support infantry, it could wind up doing so but it was designed to help the 3 medium tank companies overcome obstacles (enemy positions/formations) they could not deal with on their own and do so while they waited for Artillery/air support to keep the attack momentum going. The Panzer divisions had infantry and the infantry and tanks were supposed to work together so the Pz IVs could wind up supporting infantry but this was somewhat different than the British and French idea/s of infantry tanks.

The original Pz III was more of an infantry support tank.

37mm gun to deal with MG nests and light fortifications and three machine guns and a truck load of ammo. (121-131 rounds of cannon ammo and 4500 rounds of MG ammo).
Hey, they built a turret that would hold a 50mm gun so they filled it up with an extra machine gun and lot of ammo

We have the time between original specifications and combat results (2-4 years). The short 75 didn't penetrate any more armor than the 37mm gun did so the Pz IVs were not intended to be the anti-tank element of the Pz division. By 1940 in France they had different ammo available than in 1938 so things changed a little bit (1940 shaped charges sucked). The Pz IIIs were intended to be the anti-tank element. The short 50 restored the intended balance (not enough) and the short 75s could stay as the smoke/HE throwers. Their own AP ammo (shot/shell and HEAT) was more for self defense. And that worked, at least somewhat in NA. The Soviets had not read the script for the play/movie and T-34 and KV tanks switched everything around.

Germans should have slapped a 50mm gun in the Pz III to begin with and gone for the long gun just as soon as possible. The short 75mm in the Pz III was not the answer.
The PZ IV as a support tank, in the German plan, made some sense. It held more ammo, it would use the same bridges, transporters, etc. it was supposed to be a support tank not a break through tank.
Henschel had worked on a prototype breakthrough tank in 1937-41.

The VK 3001 (H) (or VK30.01) that weight 32 tons and had 50mm armor front and rear and 30mm sides.
Guns planned (and there is a lot of what if in many accounts) were the short 7.5cm or an adapted 10.5cm howitzer or maybe the long 5cm cannon.
they built 4 hulls, 2 were modified to make the famous SP 12.8cm gun, the plan was canceled to make the heavier 40 ton VK 3601.
At some point the goal had shifted from HE/smoke support to a dedicated anti armor vehicle mounting a 7.5cm taper bore gun that could penetrate 100mm of armor at 1500m and be protected from the same gun which meant 100mm of armor on the front and the end of a 40 ton tank and the upscaling to the Tiger I. Shortage of tungsten meant the end of the 7.5cm tabor bore gun and the switch to the 8.8cm/L56.
This is a "what if" and we don't have to follow the historical path, but the historical path was driven by doctrine, at least at times. We also had to consider some of these prototypes to show us what was technically possible. The VK 3001 for some reason used a 300hp 11 liter 6 cylinder engine and had a top speed of 25kph (?). Lack of torque?
11-12 liter engines are not going to work in 30 ton tanks unless you use a lot of gears. Yes you can build new engines. Germans had hole in their engine selection, not much except experimentals between 12 liters and 21 liters.

Germans jumped through hoops to follow their doctrine at times and at other times jumped through hoops to try to get their quick and easy adaptations to work. The Pz II based SP guns had a lot trouble with the change in weight from 9-9.5 tons to around 11 tons.

 

[tomo pauk]

Now in France in 1940 proposed doctrine was a real mess in the Field because there were nowhere near the number of MK IIIs needed to fill out the tables of organization. Which led to the hundreds of MK 1 and MK II tanks being used to fill out the numbers in the medium tank companies. Also the numbers of Pz 35(t) and Pz 38(t)s used as ersatz PZ IIIs. in two divisions.

There were about thousand of Pz-I and Pz-II manufactured before 1940, each. Up-gunning several hundred of Pz-IIs with 37mm guns would've been a prudent move IMO. Granted, not as good as the proper Pz-III, or even the Pz-38(t), but they will be able to harm the majority of the French and British tanks without the need to close to the stone-throw distances.
Lifts a lot of the burden from the Pz-III units, too.

The short 75 didn't penetrate any more armor than the 37mm gun did so the Pz IVs were not intended to be the anti-tank element of the Pz division.

In theory, maybe.
In practice, the short 75mm gun was judged to be a better anti-tank weapon in 1940.
Germans don't need to limit themselves to the 37mm on Pz-III as early as 1939, nor to limit themselves to the short 75mm on the Pz-IV (if it still gets built) and StuG-III also as early as 1939.

This is a "what if" and we don't have to follow the historical path, but the historical path was driven by doctrine, at least at times. We also had to consider some of these prototypes to show us what was technically possible. The VK 3001 for some reason used a 300hp 11 liter 6 cylinder engine and had a top speed of 25kph (?). Lack of torque?
11-12 liter engines are not going to work in 30 ton tanks unless you use a lot of gears. Yes you can build new engines. Germans had hole in their engine selection, not much except experimentals between 12 liters and 21 liters.

300 HP was too feeble power for a 30 ton tank, unless it is a specifically designed 'infantry' tank, like what the British were making. A V8 engine of the same lineage would've been better (~400 HP), and the V12 (500 HP, but less stressed) would've been even better.
Firepower - an 88mm gun/howitzer should've come in handy Realistically, start out with a good 75mm gun (a full category above the short 75mm type) and work upwards towards the realistic limits of the chassis.

That 300 HP I6 engine would've been good for the Pz-III in the Merkava-like set-up, so it can free a lot of space for the combat compartment, so the more substantial guns can be housed in the Ferdinand-like layout.

 

[ThomasP]

re the Merkava-like set-up

I present the Vickers Medium Mk II (NA), fitted with asbestos applique on the exterior for heat insulation.

3pdr (47mm) gun (3.7" Tank Mortar in CS tanks) with power traverse AND elevation (if so desired), 3-man turret with radio, engine up front with final drive, fuel and oil tanks, in the rear, engine quick-change package, entry door in the rear, with compartment between the door and the turret that could hold 4 men (if they are really good friends) or ammunition/supplies, and sloped armour on the front.

The engine QC package.

 

[Shortround6]

There were about thousand of Pz-I and Pz-II manufactured before 1940, each. Up-gunning several hundred of Pz-IIs with 37mm guns would've been a prudent move IMO. Granted, not as good as the proper Pz-III, or even the Pz-38(t), but they will be able to harm the majority of the French and British tanks without the need to close to the stone-throw distances.
Lifts a lot of the burden from the Pz-III units, too.

How much work was needed to "upgrade" the Pz II to 37mm gun? New mantlet? New periscope/sight? or new turret with two men in the turret.

I don't believe the Pz II quite gets the credit it should for it's set up. Or to put it another way, some tanks are not marked down enough for their crappy turret/crew set ups.
The Pz II had a one man turret or perhaps the so called 1 1 /2 man turret (radio operator in hull acts as loader/assistant loader to the commander/gunner in the turret. )
The Pz II used the 20mm gun with a 10 round magazine, single shot or short burst(?) at any rate the commander could fire 10 rounds or 3-5 short bursts before he needed a new magazine. Now I don't know if the radio operator actually changed the magazines or just handed a new magazine to the commander.
Compared to the French 2 man light tanks with their 37mm guns the rates of fire are very different. Commander fires one shot, then tries to reach for ammunition in the racks (which may be within easy reach, if the turret is not rotated too far out of line) and slams the round into breech and fires round number 2, repeat. French 3/4 man tanks are little unclear, radio radio operator actually slams round into breech or takes round out of rack and slaps it into the commanders out stretched hand? A help but the idea that the French tanks can actually get anywhere their listed 15rpm rate of fire is ludicrous.
A bit long winded but what is the set up for a 37mm gun in the Pz II? Single man in the turret with the radio operator slapping rounds into his out stretched hand? Bigger turret so that the loader can actually get head/shoulder/arm into turret to slap rounds into the breech? What is the rate of fire and more importantly, what is the rate of engagement?
The Pz II did not get the vision cupola until late 1940. Trying to spot a 2nd target after finishing the 1st one was difficult (so was seeing that you platoon mates may have decided to back up leaving you on your own) The 20mm cannon could take one task off the table. In 1940 it also simplified the choice of the the gunner/commander. Fire 20mm at hard targets and the MG at everything else. Didn't have to decide between 20mm AP and HE, doctrine says they didn't get HE.
How much 37mm ammo can you fit in a Pz II tank?
A 37mm gun has more firepower, as long as the ammo holds out. Is it faster to get repeat shots with or to swing onto a new target? If you you need a new turret how much does it weigh? What else aren't you getting while the shops/factories build new turrets?

In theory, maybe.
In practice, the short 75mm gun was judged to be a better anti-tank weapon in 1940.

At what ranges and using what for ammo?
How much HEAT did they have? The HEAT works (if it hits) at any range, the problem is getting the hits at long range.

Germans don't need to limit themselves to the 37mm on Pz-III as early as 1939, nor to limit themselves to the short 75mm on the Pz-IV (if it still gets built) and StuG-III also as early as 1939.

Full agreement on changing to the 50mm gun on the Pz III in 1939 if possible. Changing the 75mm on the Pz Iv and Stug may be counter productive for 1940.

300 HP was too feeble power for a 30 ton tank, unless it is a specifically designed 'infantry' tank, like what the British were making. A V8 engine of the same lineage would've been better (~400 HP), and the V12 (500 HP, but less stressed) would've been even better.

The radial engine in the M2-M3-M4 series was a 16 liter engine. The difference in torque was lot different than the difference in nominal HP. The Liberty was a 27 liter engine, one reason the British could get away with 4 speed transmissions (although that may have been a mistake in hind sight).

 

[tomo pauk]

A bit long winded but what is the set up for a 37mm gun in the Pz II? Single man in the turret with the radio operator slapping rounds into his out stretched hand? Bigger turret so that the loader can actually get head/shoulder/arm into turret to slap rounds into the breech? What is the rate of fire and more importantly, what is the rate of engagement?

Preferably a 2-men turret, like the one used on the Czech tanks once the Germans gotten their hands on these.

How much 37mm ammo can you fit in a Pz II tank?
A 37mm gun has more firepower, as long as the ammo holds out. Is it faster to get repeat shots with or to swing onto a new target? If you you need a new turret how much does it weigh? What else aren't you getting while the shops/factories build new turrets?

The 'no free lunch' rule still applies.
Against the soft targets, what the 37mm gun does with one shell, the 20mm will need to fire perhaps 3, maybe more, or maybe one will suffice. Against the hard targets, the 20mm might be completely useless.
You don't get the turrets for 20mm guns. Amount of the 37mm guns is in huge surplus anyways. Yes, the 37mm ammo count will be smaller than that of 20mm.

At what ranges and using what for ammo?
How much HEAT did they have? The HEAT works (if it hits) at any range, the problem is getting the hits at long range.

On the normal combat distances in the 1940 campaign, and with next to no HEAT ammo.
The AP shell of the short 75mm was rated for the greater penetration than any 37mm ammo, bar the APCR type.

 

[Shortround6]

I am coming to the conclusion that the Germans hung onto the Pz II to long, to be used for much of anything.
The M3 Stuart tank used a 11 liter engine. Replaced by twin 5.7 liter engines.
The M3 Half track used a 6.3 liter engine.
The Pz II used a 6.2 liter engine.

You have the political problem of canceling contracts with German companies and increasing production with Czech companies but a faster change over to the 38(t) chassis might have paid dividends.

 

[Shortround6]

Preferably a 2-men turret, like the one used on the Czech tanks once the Germans gotten their hands on these.

Waste of resources.

Against the soft targets, what the 37mm gun does with one shell, the 20mm will need to fire perhaps 3, maybe more, or maybe one will suffice. Against the hard targets, the 20mm might be completely useless

Germans didn't issue 20mm HE to the tanks. Soft targets were machine gun only.
French had 500-600 light tanks/armored cars in service, not counting over 1000 old Renault FTs.
Also had 2800-3000 unarmed but armored supply vehicles/tractors in service.
Pz IIs that had been up armored can sit and duke it out with all the two man light tanks with short 37mm guns. Neither one can hurt each other. Got to watch out for the long barreled ones though

You don't get the turrets for 20mm guns. Amount of the 37mm guns is in huge surplus anyways. Yes, the 37mm ammo count will be smaller than that of 20mm.

Reduce orders for the Pz II, assign them to recon, build more Pz 38(t) and Pz IIIs.
Germans yanked at least 18 rounds of 37mm ammo from the Pz 38 to fit in the extra crewman, and that was in a larger tank, Not a lot larger but at least some.
38(t) might have carried 72-74 rounds of 37mm compared to the 121-131 of the Pz III. 38 (t) gun was also a bit more powerful.

Basically the Pz II was a lost cause. Anything more that minor upgrades was delaying work they should have doing on other things.

 

[tomo pauk]

Waste of resources.

Not for 1939-40.

Germans didn't issue 20mm HE to the tanks.

Are we positive about that?

Reduce orders for the Pz II, assign them to recon, build more Pz 38(t) and Pz IIIs.

Good idea.

 

[Shortround6]

Are we positive about that?

That is what this book seems to say.

It doesn't say it exactly but gives different recommendations for use of guns for different targets.
The instructions lump all cannon ammo together. No difference for AP ammo vs HE ammo for different types of targets, like AT guns with shields. Use cannon to shoot through the shields, use mg when firing in the flank of the gun past the shield.
Tankers may have gotten some HE ammo from AA units?
They had 180 rounds of 20mm ammo in the Pz II.
The HE ammo may have been issued later for Armored cars or for tracked recon vehicles.

The early 20mm gun fires slow (280rpm/ 4 1/2 rps) and you have to change magazines after 10 rounds, not the 20 rounds of the AA gun.
Everybody quotes the 120 rounds per minute effective rate of fire for the AA gun. Needing to the change the magazines 11 times (starting with loaded gun) vs changing magazines 5 times for the AA gun makes no difference to the practical rate of fire apparently
Pz II had 2250 rounds of MG ammo in the early models. Pz I held about the same(?) but the two MGs were feed by 25 round magazines. Ps II used the 75 round drum MG 34 for a much more effective weapon on soft targets.

If a commander wants to change 20mm ammo he has to take the current magazine out and put the new type of ammo in?

 

[tomo pauk]

Excerpt from the book about the Pz-II from Jenz, wrt. the experiences of 1940:



Use of HE ammo was also noted during the Norwegian campaign.

If a commander wants to change 20mm ammo he has to take the current magazine out and put the new type of ammo in?

Not a problem, especially with teh small magazines. Although, loading alternatively the magazines with AP and HE ammo would not be unheard of.

 

[Admiral Beez]

Panther was indeed 10 tons overweight for what it was offering, and it was too big, making for a rewarding target.

Swap out the Panther's torsion bars for the Panzer IV's leaf spring double-bogie suspension and we can get the height down by at least a foot.

 

[Shortround6]

Excerpt from the book about the Pz-II from Jenz, wrt. the experiences of 1940:

Use of HE ammo was also noted during the Norwegian campaign.

Not a problem, especially with teh small magazines. Although, loading alternatively the magazines with AP and HE ammo would not be unheard of.

Thank you for the correction/s.
Interesting comment about the MG 34. It was not trouble free and it used 3 different feed set ups, which may have had individual problems.
One does wonder about the lack of use of the Czech 37 in other German vehicles, on paper it has several good points. The British were in no hurry to change it.
Free guns and ammo From the US as NATO aid tipped the balance.

 

[tomo pauk]

One does wonder about the lack of use of the Czech 37 in other German vehicles, on paper it has several good points. The British were in no hurry to change it.

Being very heavy is/was probably a good side for a tank-mounted MG, it will be not so easy to over-heat, and parts are probably over-sized, that can help with reliability. Ironically, seems like the Besa was more used as a tripod-mounted MG by the Germans.

I stand by my comment that Germans were often ignorant (arrogant?) about how to extract the best mileage from the captured assets.

BTW - seeing that Germans were satisfied how the 20mm did against some targets, perhaps the Pz-I should've been with the similar weapon? Even the Polish TKS tankette was outfitted with an autocannon in some token numbers, and Pz-I was much bigger and heavier. The Pz-I was retrofitted with the Breda 20mm back in the SCW.

 

[z42]

If the engine+transmission is in the rear, and the turret+gun barrel is in the front, there is still a lot of weight in the extreme front. You still have the possible case of muzzle digging in the terrain on an uneven ground.
A shorter engine might've helped in both cases, though. Or, be very advanced, and rotate the engine by 90 deg if the all-rear layout of the powerpack is chosen, as it was the case with the T-44, so the whole combat compartment can be shifted back by 60-90 cm?
T-34-76 vs. the T-44-85:

Yes, but in retrospect it might be possible to do better than the T-34 even with a rear transmission and a longitudinally mounted engine. Have more angle on the upper front hull plate, put the driver in a more inclined position and look out through a periscope, and you could get a longer but lower hull? Like on the Centurion (pic of a much newer version, but the basic layout is the same as the Mk I that just missed WWII):

 

[z42]

When can the Germans start tapping into Czech tank production, and how quickly can that be scaled up? If possible to do better here than in the OTL, maybe switch to Pz38-derived designs for anything where a light chassis is sufficient, shut down domestic light tank production (Pz I and II), and convert the domestic tank production to heavier ones?

• A Pz38 derived 10.5cm SP howitzer instead of the Wespe?
• Can we get the Hetzer into production sooner?
• And Pz38/Hetzer derived SPAA (there was the single 20mm variant, but maybe the slightly bigger Hetzer chassis can take a single 37mm, with an open turret with some minimal splinter protection, later the Kugelblitz style enclosed turret with twin 30mm?) , recovery vehicles, bridge layers, ammo carriers etc.?

 

[tomo pauk]

Yes, but in retrospect it might be possible to do better than the T-34 even with a rear transmission and a longitudinally mounted engine. Have more angle on the upper front hull plate, put the driver in a more inclined position and look out through a periscope, and you could get a longer but lower hull? Like on the Centurion (pic of a much newer version, but the basic layout is the same as the Mk I that just missed WWII):

It was certainly possible to do better than the T-34. Eg. the transversal transmission might save perhaps half a meter? Add to the your suggestions, for even greater effect. Having a shorter, more compact engine (like the German V12s, or Kestrel, or Merlin/Meteor, or a V8) also can help a lot.
On a big & long tank, the %-age of the tank taken out by the engine is smaller than on the bigger tank, so the longitudinal engine placement can be less of an issue. Eg. on the Matilda II, engine+transmission took 43% of the hull length, while at Valentine it was 49%, Valentine being shorter to begin with.

When can the Germans start tapping into Czech tank production, and how quickly can that be scaled up? If possible to do better here than in the OTL, maybe switch to Pz38-derived designs for anything where a light chassis is sufficient, shut down domestic light tank production (Pz I and II), and convert the domestic tank production to heavier ones?

• A Pz38 derived 10.5cm SP howitzer instead of the Wespe?

The earlier they start doing it, the better their tanks/AFVs became. They can start as early as Spring of 1939.
The Pz-38 turned into the 10.5cm SP howitzer would've been a much less compromised and less stressed vehicle than the original Wespe, possibly with the bigger ammo loadout.

Can we get the Hetzer into production sooner?

If it dawns on the Germans very early, then yes.

And Pz38/Hetzer derived SPAA (there was the single 20mm variant, but maybe the slightly bigger Hetzer chassis can take a single 37mm, with an open turret with some minimal splinter protection, later the Kugelblitz style enclosed turret with twin 30mm?) , recovery vehicles, bridge layers, ammo carriers etc.?

Hetzer is the halfway house between the Pz-II and the full-blown tank like the Pz-III or IV. So it makes a lot more sense to turn it into a weapon carrier of any sort, than to 'steal' from the tank/StuG production, while it will be much better as a platform than the Pz-II,

 

[Elan Vital]

Yes, but in retrospect it might be possible to do better than the T-34 even with a rear transmission and a longitudinally mounted engine. Have more angle on the upper front hull plate, put the driver in a more inclined position and look out through a periscope, and you could get a longer but lower hull? Like on the Centurion (pic of a much newer version, but the basic layout is the same as the Mk I that just missed WWII):

Considering how common rear drive tanks were even after the adoption of thick frontal armor and/or heavy turrets and guns including in the postwar era (almost all NATO tanks), it seems at least that it was still fine from a mass distribution standpoint.

In fact, even if front vs rear drive ended up being a wash in terms of mass distribution, the remaining advantages of rear drive (including overall weight reduction even if it wasn't better distributed) were probably still worth it, especially for the big cats and front casemate Jagdpanzers and StuGs.

I see no particular technical obstacle for providing Pz 38-derived Wespes earlier, and indeed accross the board for all front-engine/rear casemate Pz II and Pz 38 derivatives. It's more a matter of having the people and ressources to do it earlier. I'd argue that a Wespe-like vehicle might have been a better platform for the 15cm SiG than the Sturmpanzer II, by the way (basically would have been a Pz II-based Grille). It also seems that all these front engine variants were more convenient than the previous rear-engine Marders and SPG/SPHs.

Hetzer used some Pz 38(t) n.A parts so the historical version could not have existed any sooner than 1942/early 43, but certainly much earlier than OTL which was only down to the specific issues with StuG 3 production being bombed. In principle, "Hetzer"-like vehicles based on the basic Pz 38(t), Pz II (and Jagdpanzer IV analogues on Pz III and IV chassis) could also have existed sooner, albeit in more lightly armored or armed forms to account for the weaker engines and suspensions of these vehicles earlier in the war.

 

[z42]

Swap out the Panther's torsion bars for the Panzer IV's leaf spring double-bogie suspension and we can get the height down by at least a foot.

I don't think the torsion bars would require a full foot. Just eyeballing your picture, maybe 10-15cm?

As for alternative suspensions, what about hydropneumatic? I'm not aware of any applications to tanks in the WWII time-frame, but AFAIU oleo struts were used in aircraft so at least the principle was well understood.