Sherman vs the Panzer IV

[Colin Williams]

There has been quite a debate in this thread about whether it is impressive or not that the M4 Sherman was produced by the US, given that the US was the world's greatest industrial power and yet had neglected medium and heavy tank development. IMHO the M4 was an impressive accomplishment when one considers how the other major powers managed to develop their equivalent tanks.

 

For the Germans, the ability to upgun the PzIV was to some degree a matter of luck. The PzIII was intended to be the MBT with the PzIV simply providing HE support with the 75mmL24. If the PZIV turret had been unable to take the 75mmL48 (or L43 for that matter), history would be judging the Germans harshly for the inadequacies of the PzIII with the 50mmL60 and the long period of time between the upgunning of the PzIII and the appearance of a new tank armed with the 75mmL48 or larger gun.

 

By contrast, the Soviet development of the T34 was a culmination of the many years devoted to improving the BT series. As with the PzIII and PzIV, one could argue that that Soviets barely avoided producing an incremental improvement on the BT7 with the T34, but I see it more as the logical step forward in a steady evolution of Soviet tank design. The T34 showed what one could accomplish with long-term tank R&D.

 

The British suffered the fate the Americans narrowly avoided, perhaps to some degree excusable because they were operating under the stress of wartime, but they were trapped with small-turreted cruiser tanks that could not be upgunned to anything like a 75mm until the Cromwell appeared on the battlefield in 1944. Even then its upgunning to a high velocity gun equivalent to the American 76mm or the German 75mmL48 required a redesign into the Comet, which didn't see action until 1945.

 

From this perspective, for the Americans to design and build the Sherman in 1941 was quite an accomplishment. The existing medium tank, the M2, was entirely derivative of the light tanks that culminated in the Stuart and as unable to carry heavier armament as the British cruisers. Yet the lesson that the Americans took away from the German conquest of France in 1940 was that the German PzIV, with its 75mm gun, was the most dangerous German tank. The obvious solution was to match the PzIV with an American tank mounting a 75mm, one that could be produced in mass quantities, but, as noted above, the M2 wasn't up for job beyond its suspension and powerplant. So, adapt the cast hull of the Somua S35, design a turret to take a modified French 75mm gun, put both on top of the vertical volute suspension of the M2, and you have the medium tank to beat the PzIV. It was a leap in a new direction and pretty impressive considering that the limited work in America on medium and heavy tanks in the 1930s.

[Guest aevans]

So, adapt the cast hull of the Somua S35, design a turret to take a modified French 75mm gun, put both on top of the vertical volute suspension of the M2, and you have the medium tank to beat the PzIV. It was a leap in a new direction and pretty impressive considering that the limited work in America on medium and heavy tanks in the 1930s.

 

I think you're missing an entire step here.

[Colin Williams]

I think you're missing an entire step here.

 

The M3?

[CaptLuke]

The M3?

 

There's that. The Sherman has no significantly better gun than the M3 till 1944.

 

For the Germans, the ability to upgun the PzIV was to some degree a matter of luck. The PzIII was intended to be the MBT with the PzIV simply providing HE support with the 75mmL24. If the PZIV turret had been unable to take the 75mmL48 (or L43 for that matter), history would be judging the Germans harshly for the inadequacies of the PzIII with the 50mmL60 and the long period of time between the upgunning of the PzIII and the appearance of a new tank armed with the 75mmL48 or larger gun.

 

How is being able to upgun the PzIV more 'luck' than any other up-gun? Were the British simply lucky that the 17lbr fit in a Sherman or is that another reason to praise the Sherman's design?

 

Also I think the Germans would have made do if it hadn't fit. The PzIII specials were adequate in the west for quite awhile. They also could have:

1. 
    
   
2. Shifted production to 75/48 and 75/70 Assault gun variants of the PzIV and used these to stiffen PzIII units
   
3. Armed the PzIV with a gun smaller than the 75mm L48 but bigger than the 50mm. The Skoda 66mm Pak comes to mind though I'm not sure what its development dates were.
   
4. Put one of the designs that were already in development when they met the T34 into production as a stop gap. I think I could argue that it was the PzIV's ability to take the 75mm L48 that enabled the Germans to scrap their existing work and go straight to the Panther rather than rushing a more powerful, but outmoded, design into production in '42
   

Edited July 31, 2010 by CaptLuke

[Guest aevans]

The M3?

 

Bingo. It was very much an interim, expedient design, but it contributed significant design and automotive features to the M4.

[Gammenon]

There's that. The Sherman has no significantly better gun than the M3 till 1944.

 

 

 

How is being able to upgun the PzIV more 'luck' than any other up-gun? Were the British simply lucky that the 17lbr fit in a Sherman or is that another reason to praise the Sherman's design?

 

Also I think the Germans would have made do if it hadn't fit. The PzIII specials were adequate in the west for quite awhile. They also could have:

1. 
    
   
2. Shifted production to 75/48 and 75/70 Assault gun variants of the PzIV and used these to stiffen PzIII units
   
3. Armed the PzIV with a gun smaller than the 75mm L48 but bigger than the 50mm. The Skoda 66mm Pak comes to mind though I'm not sure what its development dates were.
   
4. Put one of the designs that were already in development when they met the T34 into production as a stop gap. I think I could argue that it was the PzIV's ability to take the 75mm L48 that enabled the Germans to scrap their existing work and go straight to the Panther rather than rushing a more powerful, but outmoded, design into production in '42
   

 

Would it be possible to install that gun in Panzer III?

[Hittite Under The Bridge]

Doctrine, doctrine, doctrine.

[Kentucky-roughrider]

Doctrine, doctrine, doctrine.

 

While that is very important; your equipment must also match your doctrine. If you doctrine call for fast moving and hard hitting tanks; a slow moving tank like the Matilda 2 will not cut it without a major change to that doctrine.

[CaptLuke]

Would it be possible to install that gun in Panzer III?

 

Honestly don't know. The way the Germans went from 50/60 to 75/24 in the PzIII seems to indicate the turret was maxed out at that level but it could just be that the Germans were thinking a whole new weapon/caliber wasn't worth the effort when it still would have been outmoded for tank to tank use and inferior to the 75/24 for HE.

[Guest aevans]

While that is very important; your equipment must also match your doctrine. If you doctrine call for fast moving and hard hitting tanks; a slow moving tank like the Matilda 2 will not cut it without a major change to that doctrine.

 

Ummm...the Matilda was made to be an infantry tank, which fit the British doctrine just fine. The problem was that the doctrine was not particularly appropriate. Likewise, the US made tanks and tank destroyers to fit its doctrine. But the doctrine had problems. Arguabley the Germans and the Soviets were the only major powers to build tanks to fit a realistic doctrine, and even those doctrines missed some points that had to be learned through experience.

[Kentucky-roughrider]

Ummm...the Matilda was made to be an infantry tank, which fit the British doctrine just fine. The problem was that the doctrine was not particularly appropriate. Likewise, the US made tanks and tank destroyers to fit its doctrine. But the doctrine had problems. Arguabley the Germans and the Soviets were the only major powers to build tanks to fit a realistic doctrine, and even those doctrines missed some points that had to be learned through experience.

 

I understand that, I meant if you tried to use a tank like the Matida in a role that required a fast moving tank like a Panzer Mark III, you would have problems or worse if you tried to use a lighter less well armored tank like a cruiser tank assualt role there would be problems for the crew.

[Mobius]

From reading it didn't seem the German Army tried very hard to salvage their damaged PZIV. One crew went through 4 vehicles in a year. Gun damaged by shell - blow up tank and walk back to base. Turret rotation damaged by glancing hit - blow up tank and walk back to base. Tank gun hits barn door - return tank to shops - tank is used for parts. Tank hits mine -track damaged - blow up tank. If your are in a war of attrition why the *heck* aren't they trying to keep every last tank in the game?

[mnm]

Because sometimes wars are not all made of advances and if you don't hold the battlefield for yourself you can't recover material at leisure, sometimes you recovery means are not enough or simply do not exist any longer...

[binder001]

The Germans did recognize the importance of recovery of damaged armor from the battlefield, they were just often too short on the resources to allow it to be done. Further, as mentioned above, they were fighting on the defense, and if they lost or pulled back, the tank wrecks stayed in Allied hands. The US Army booklet "German Tank Maintenance in WW2" makes the point that the Germans tended to build complete new tanks versus providing lots of spare parts for the existing tanks. A new Pz IV might arrive at a German tank unit and be cannibalized for parts to keep several others going. The US is often citicized for the large logistics "tail", but a US tank unit would be much more likely to be provided with spare parts and have access to field shops and theater depots for repair as well as having more new tanks brought up. THe US tradition of auto repair at that time emphasized home repair with spare parts and this carried into the Army/Marines. The US also had more resources available to provide a greater number of tank recovery vehicles. When the battlefield couldn't be held or recovery was impractical then the wrecks would be destroyed. There is/was an interesting photo sequence of US combat engineers placing charges in a wrecked Pz IV and M10 to demolish the carcasses.

[cbo]

Also I think the Germans would have made do if it hadn't fit. The PzIII specials were adequate in the west for quite awhile. They also could have:

1. 
    
   
2. Shifted production to 75/48 and 75/70 Assault gun variants of the PzIV and used these to stiffen PzIII units
   
3. Armed the PzIV with a gun smaller than the 75mm L48 but bigger than the 50mm. The Skoda 66mm Pak comes to mind though I'm not sure what its development dates were.
   
4. Put one of the designs that were already in development when they met the T34 into production as a stop gap. I think I could argue that it was the PzIV's ability to take the 75mm L48 that enabled the Germans to scrap their existing work and go straight to the Panther rather than rushing a more powerful, but outmoded, design into production in '42
   

 

As for the Germans being "lucky" that that 7,5cm L/43 fit, I think that is a reasonable statement. The gun was shoehorned in, placed far forward in the turret to maintain room for the commander and sacrificing any hope of increasing the front turret armour beyond 50mm.

 

But of course, they had other options.

 

One was to mount the 5cm L/60 gun in the Panzer IV, an idea tried out in the spring of 1941. That idea was dead by October. A guess would be that the realities of the post June 1941 Eastern Front experience had something to do with it.

 

Another proposal was a modified version of a 7,5cm L/40 gun proposed for the StuG III. Shortened to L/33 resulting in a muzzle velocity of 580 m/s, it could penetrate 59mm of armour at 400 meters. With subcaliber ammunition fired at 875 m/s it could manage 86mm at 400 meters. With a proposed taper-bore barrel (7,5cm -> 5,5cm) it could reach 700 m/s and penetrate 68mm at 400 meters.

 

Not much better than the 5cm L/60 and a far cry from the ~95mm of the 7,5cm L/43 (~110 with subcaliber ammo).

[Homerr]

From reading it didn't seem the German Army tried very hard to salvage their damaged PZIV. One crew went through 4 vehicles in a year. Gun damaged by shell - blow up tank and walk back to base. Turret rotation damaged by glancing hit - blow up tank and walk back to base. Tank gun hits barn door - return tank to shops - tank is used for parts. Tank hits mine -track damaged - blow up tank. If your are in a war of attrition why the *heck* aren't they trying to keep every last tank in the game?

 

But was this crew issued brand new panzers, or ones that were refurbed after being recovered?

[Guest aevans]

I understand that, I meant if you tried to use a tank like the Matida in a role that required a fast moving tank like a Panzer Mark III, you would have problems or worse if you tried to use a lighter less well armored tank like a cruiser tank assualt role there would be problems for the crew.

 

But the point is that armies don't do that. They tend to develop and acquire AFVs that more or less fit their perceived doctrinal requirements. That's because technical requirements are (and ought to be) derived from doctrinal rules. Mistakes have been made in this regard, but not nearly as often as many seem to think. So the thing to get right is doctrine, and then make sure your technical requirements are true to that doctrine.

[Colin Williams]

Bingo. It was very much an interim, expedient design, but it contributed significant design and automotive features to the M4.

 

I'm not sure about that but will check. It seems to me that M3 and M4 development tracks were more in parallel than in series.

[Arminius]

While that is very important; your equipment must also match your doctrine. If you doctrine call for fast moving and hard hitting tanks; a slow moving tank like the Matilda 2 will not cut it without a major change to that doctrine.

 

+ 1.

 

and also, if you have the Doctrine AND the arms for it right, it won´t do, if you got not enough FUEL.

 

Please don´t be so oversimplifying!!

 

It´s NOT that easy, there´s not ONE reason for desaster, the Germans were NO fools!

 

Hermann

[Colin Williams]

A visual guide to French influence on the development of US medium tanks -

 

US M2 Medium Tank

 

 

US T5E2

 

French Char B1bis

 

US M3 Medium Tank

 

French Somua S35

 

US M4A1 Medium Tank

[Guest aevans]

One could also point to the front drive sprockets and roadwheels mounted in pairs as evidence of German influence. Aditionally, the first mark of the Churchill tank had a 3 inch howitzer mounted in the hull.

 

As for the French influence on the Sherman hull, according to the AFV Database, cast and welded hulls were being manufactured at the same time in different factories. ISTR it had to do with the capabilities of the particular plant and its subcontractors, not what some designer thought about hull construction.

[Colin Williams]

One could also point to the front drive sprockets and roadwheels mounted in pairs as evidence of German influence. Aditionally, the first mark of the Churchill tank had a 3 inch howitzer mounted in the hull.

 

As for the French influence on the Sherman hull, according to the AFV Database, cast and welded hulls were being manufactured at the same time in different factories. ISTR it had to do with the capabilities of the particular plant and its subcontractors, not what some designer thought about hull construction.

 

I would also be inclined to downplay the connection except for the fact that in 1940 French representatives were in the US arranging for production of the S35 and supposedly sharing plans and information on casting technology.

[shep854]

Did the French design their tanks around radial aircraft engines?

[Guest aevans]

I would also be inclined to downplay the connection except for the fact that in 1940 French representatives were in the US arranging for production of the S35 and supposedly sharing plans and information on casting technology.

 

Who were they sharing it with, and was that company involved in the production of M4s with cast upper hulls? See, you're trying to stretch an isolated commercial venture into a major influence on US AFV technology. Did it have an influence on Sherman's with cast upper hulls? Maybe, maybe not, but there is no such thing as smoking guns in history.

[Guest aevans]

The Sovs and Christie running gear?

 

And torsion bars on almost everything else? And the Christie suspension on British Cruisers? Christie suspension technology was purchased as a finished product, just like engines or guns would be. It didn't influence design beyond making room to install it.

 

Edited to add:

 

If you look closely at the M4 HVSS suspension, there's some affinity with the fundamental feature of Christie's suspension (the conversion of vertical motion to horizontal using a bell crank). So is that a definite design influence, form following function, or a little bit of both?

Edited August 4, 2010 by aevans