Tank & AFV armament alternatives, 1935-45

[Elan Vital]

I would agree, the point is they were making too many different types. With the Matilda II, Valentine, and Churchill all offering the same gun, roughly the same speed and around the same armor at the same time. Only real difference was the amount ammo carried and the extra machine gun in the Churchill and that increase in "fighting power" was not great (more in the minds of the designers/committee) They got around to increasing the gun and armor of the Churchill..........eventually.
Using the infantry tanks as ersatz cruisers is really admitting they had screwed up the cruiser tank implementation in spectacular fashion. We can argue about the doctrine, specification but the supplied tanks didn't have the reliability to perform the mission. Sending the Cruisers into the enemy rear areas to force him to retreat doesn't work well when most of your tanks are going to breakdown before they shoot up very much rear area "stuff" (supply dumps, head quarters, heavy artillery and so on). Not much enemy AT gun or counter attack by enemy tanks needed. British Cruiser tanks were not capable of staying running in large numbers over 200-300 miles of movement.

P.M. Knight answers some of this in his books on early Cruisers. The powers that be expected the battle tempo to be sufficiently slow to use the tanks for some time, then send them back for overhaul/major maintenance. So specific durability/reliability figures were not required. Admittedly, my understanding is that a lot of WW2 belligerants thought the same as well at the time.

My understanding is that it is only in 1942-43 that the British set a specific value, 3000 mile life for Cruisers and 2000 mile life for Churchills before overhaul, without failure/replacement of a major assembly. Cromwell was the first Cruiser to meet this, A30 and Comet met it as well, late Churchills met it, Black Prince was still in development but it was apparent it would have met the requirement. Late Covenanter was close, late Crusader sorta was getting there, but initially it had a pretty mediocre life of 1000-1500 miles with many systemic issues.

As for 2 pdr, I also agree that having the normal full suite of full caliber ammo almost from the start would have helped a lot. The French for example started experimental work/trials on AP ammo for their casemate guns and the 47mm tank gun in 1932 IIRC, starting with uncapped AP shot (still better against thick plate than the atrocious 2pdr APHE which had an excessively large cavity), and entering service with APBC with hardened tip (APC for tank guns). Admittedly, old APHE or uncapped ammo was actually quite common among low caliber gun users (Czechoslovakia, Sweden, Germany...)

 

[Shortround6]

I have purchased P.M. Knight's book on the Crusader and I am working my way through it. I may get a few more of his books but I can't afford the complete collection.
I do recommend this book based on what I have read so far. There is a lot of 'stuff' behind the scenes that winds up causing trouble later. Like 'just cut 6 1/2 inches' from the height of the Liberty engine. Not that the Liberty was trouble free in the early cruiser tanks, but it got worse in the Crusader which is kind of the opposite of what you would expect after you already had around 700 in service. It was supposed to have been the 'safe' choice.

To cut the British some slack the Fighting in NA was very different than what most people contemplated for combat in Europe in the 1930s. The Soviets and Americans may not have had actual mileage requirements but the size of their countries made them more mindful of distance than some other countries.
For the French it is difficult to find a 600 mile difference from the northern border to the border with Spain. You can do it but you really have to use the corners
For the British and going cross country it it about 700 miles from John O' Groats to Land's end so the idea of doing such journeys without maintenance is not surprising. Also the extensive rail networks didn't require it. For the US it is over 800 miles from Boston to Charleston and over 1600 miles from the top of the coast of Maine to Miami Florida. Yes the US had rail roads but they were expecting their motorized army to go further distances just to get to battle sites than the Europeans.
And likewise the tanks/vehicles they needed for 'colonial duties' were different than those needed for European conflicts.

Combine the distances traveled with the wear and tear caused by the Desert environment and things were worse for everybody, including the Germans and Italians.

But the British were expecting Cruiser tanks to go 25-35mph on roads, they were expecting them to operate "behind the lines" quite possible beyond even heavy artillery support and with a lot of zigging and zagging, not drive 10 miles behind the enemy front lines, drive around for an hour and then drive 10 miles back. You are going to loose some tanks due to break downs. For every tank that makes it to 1000 miles, in order to have a 500 mile average, you had to have tank that broke at 1 mile

 

[tomo pauk]

Soviets were actually experimenting with the gun that was equivalent of the M1936 (a.k.a. F-22) 'multi-purpose' gun, at least on the KV-1:



It was just a plain-vanilla KV-1 otherwise.
This ZiS-5 (F-22) version was supposed to do fire the 6.5kg projectile at 780 m/s (that is probably the very hot load ammo version), with penetration ability of 75mm at 1000m, 90 deg hit; ammo compatibility with the M1902/30, M1936 (F-22) and M1939 (USV) guns is noted:



This kind of a tank gun would've been very handy to have in 1942 and 43.

German modification of the captured KV-1, featuring a tank gun as was used on the Pz-IVG for example.

 

[bf109xxl]

Soviets were actually experimenting with the gun that was equivalent of the M1936 (a.k.a. F-22) 'multi-purpose' gun, at least on the KV-1:

View attachment 810470

It was just a plain-vanilla KV-1 otherwise.
This ZiS-5 (F-22) version was supposed to do fire the 6.5kg projectile at 780 m/s (that is probably the very hot load ammo version), with penetration ability of 75mm at 1000m, 90 deg hit; ammo compatibility with the M1902/30, M1936 (F-22) and M1939 (USV) guns is noted:

BR-350B for F-34/ZIS-5 was able to penetrate up to 78 mm at 1000m. The difference between 50clb and 41clb versions of the ZIS-5 was less significant than the projectile design, the use of the F-34 barrel made the ZIS-5 much cheaper. The Soviets tested the F-27 with the ballistics of the AA 3-K (813 m/s), however it was not well suited for the use in the KV turret. The Soviets did not need any 76mm guns with a higher ballistics. They need 85-mm. The limiting factor was the turret ring diameter - the Soviets needed American/British machines for mass production of armor plates with a 1600mm turret ring cutout.

View attachment 810471

This kind of a tank gun would've been very handy to have in 1942 and 43.

The mass-produced F-34/ZIS-5 with the BR-350B projectile fully corresponded these parameters .

 

[tomo pauk]

What the Soviets reckoned during the war, wrt. their tank/AFV guns vs. German tanks. Note that armor of the selected parts of the German tanks is 'normalized', ie. the vertical equivalent of the slanted (where applicable) armor is specified to level the playing field. tanks listed start with Pz-I (T-I) and end with Tiger B, a.ka. Tiger II (T-VI-B). Note two Pz-IV graphs, for 'normal' and for up-armored.



Several conclusions can be drawn from the graph, IMO.
Soviets were in disadvantage due to not up-gunning their tanks in early 1943, if not already in 1942 (when we account for the German self-propelled vehicles - tanks and other AFVs - with the long-barrel gun ability to destroy Soviet tanks well beyond 1km mark).
The 85mm gun would've helped a lot there.
For the peace of mid, the 100 and 122 mm self-propelled cannons should've also been in service by 1943.

 

[MikeMeech]

No problemo



Unfortunately, we are unlikely to ever know the answers to all these whys.
Both French and British tanks are worthy of their equivalent of the 'Secret horsepower race' book, where a dedicated researcher will invest his time, effort and money to sift through the files of the War Ministries and Army commands in order to unearth the real stuff. Some of the whys for the British tanks were covered in the book 'The great tank scandal' by David Fletcher, but it ought to be much more to read, and with good footnotes.

Hi
For a recent single volume study, of what has been discussed on this thread, I would recommend 'The Second World War Tank Crisis; The Fall and Rise of British Armour 1919-1945' by Dick Taylor, Pen & Sword 2021. It covers the majority of the problems that arose and why.

Mike

 

[Shortround6]

I am working my (haphazardly) through some books on early British armor. So far no real explanation on the lack of HE round for the 2pdr and 6pdr. Just trying to find when it was adopted is tough.
What the troops thought seems to be at odds with the high command. Troops wanted HE. In late 1942 the British crews in Crusaders with 2in smoke bomb throwers were getting 2in HE bombs from the infantry with their stronger propelling chargers (a lot of the smoke ammo issued to tanks had light propelling charge (12 grains?) and had a max range of 120 yds. OK for screening your own tank but being able to lob smoke shells 300-500yds to screen the gun itself might have been more useful. Tankers also used the HE bombs with the standard charge (47grains?) and fired them flat at close range. The infantry mortar had a solid back end. The tank bomb thrower was a breech loader. It went through several marks and some may have been stronger than others.
As mentioned earlier, the troops wanted 7.9mm AP and incendiary ammo. They were willing to take captured German ammo and use it their guns. They wanted more effective ammo of all types. They weren't getting it.
British tank commanders didn't have a lot of good choices. Sit back and get shot, retreat and get shot until you were out of range, Charge like manics and get shot until you got close enough for the MG to be effective and drive over the AT gun.
Not coming up with new/better AP rounds for two years after the BoF (6pdr AT guns were issued before the better 2pdr AP shot) just seem to get glossed over.

 

[yulzari]

I am working my (haphazardly) through some books on early British armor. So far no real explanation on the lack of HE round for the 2pdr and 6pdr. Just trying to find when it was adopted is tough.
What the troops thought seems to be at odds with the high command. Troops wanted HE. In late 1942 the British crews in Crusaders with 2in smoke bomb throwers were getting 2in HE bombs from the infantry with their stronger propelling chargers (a lot of the smoke ammo issued to tanks had light propelling charge (12 grains?) and had a max range of 120 yds. OK for screening your own tank but being able to lob smoke shells 300-500yds to screen the gun itself might have been more useful. Tankers also used the HE bombs with the standard charge (47grains?) and fired them flat at close range. The infantry mortar had a solid back end. The tank bomb thrower was a breech loader. It went through several marks and some may have been stronger than others.
As mentioned earlier, the troops wanted 7.9mm AP and incendiary ammo. They were willing to take captured German ammo and use it their guns. They wanted more effective ammo of all types. They weren't getting it.
British tank commanders didn't have a lot of good choices. Sit back and get shot, retreat and get shot until you were out of range, Charge like manics and get shot until you got close enough for the MG to be effective and drive over the AT gun.
Not coming up with new/better AP rounds for two years after the BoF (6pdr AT guns were issued before the better 2pdr AP shot) just seem to get glossed over.

The Soviets with their Valentines made much use of the 2" breech loading mortar in lieu of HE gun fire. Using their own HE mortar rounds. My old ex Red Army acquaintance said he kept lots of them to hand together with Soviet smoke mortar rounds to screen forward movements. He relied upon the small size and quietness of his Valentines and the longer range Soviet mortar smoke rounds enabled him to take leaps into dead ground to flank Axis tanks and AT guns.He used a lot of German ammunition for his BESA as it was more readily available than the Soviet resupplies to him.

 

[bf109xxl]

What the Soviets reckoned during the war, wrt. their tank/AFV guns vs. German tanks. Note that armor of the selected parts of the German tanks is 'normalized', ie. the vertical equivalent of the slanted (where applicable) armor is specified to level the playing field. tanks listed start with Pz-I (T-I) and end with Tiger B, a.ka. Tiger II (T-VI-B). Note two Pz-IV graphs, for 'normal' and for up-armored.

The Soviets faced the normalization effect already in 1941 - it was discovered that the T-34 was penetrated by a 50mm German AP shell, although given the slope of the armor this should not have been the case. I have definitely written about this on the forum, probably more than once. For German tanks, the normalization effect was of less importance, as the angles of inclination of their armor were small - with the exception of the Panther, but its armor did not impress the Soviets.

View attachment 811154

Several conclusions can be drawn from the graph, IMO.

And why are you so shy about citing the source of the information?

Unfortunately, the analysis of the reasons for making a particular decision is either absent or insufficient in this book. And in the case of the Soviets, the limited industrial capabilities were (almost always) the decisive factor. Most of the alternatives proposed here are completely unacceptable for the Soviets because of the excessively high technology requirements. It is pointless to propose deliberately unrealistic alternatives. And a deeper knowledge is needed to judge the reality of the realization of one or another alternative.

Soviets were in disadvantage due to not up-gunning their tanks in early 1943, if not already in 1942 (when we account for the German self-propelled vehicles - tanks and other AFVs - with the long-barrel gun ability to destroy Soviet tanks well beyond 1km mark).
The 85mm gun would've helped a lot there.

The main parameter that limited the use of any projectiles with high armor penetration was the round length. Since the turret ring diameter was limited - the Soviets didn't have a suitable machine for mass production of the turret rack with diameter exceeding 1500 mm until late 1943 (rather 1944), thus no any 76-mm gun with more powerful ammunition or any 85mm gun requiring a 1600mm turret rack could be mounted in the mass-produced T-34 until 1944. The Soviets were not able to provide the necessary production capacity of 1600mm turret racks earlier. No alternative should ignore this problem - the round length should not have exceeded a certain value either. Therefore, NO variants with either reinforced 76-mm or 85-mm guns for the T-34 earlier. Only self-propelled artillery units with a casemate-type design allowed longer rounds - and that's the reason why the SU-100 appeared.

For the peace of mid, the 100 and 122 mm self-propelled cannons should've also been in service by 1943.

If the Soviets could initially provide sufficient AP shell quality, the 85mm would have sufficed to destroy German tanks, however they wanted not only AP capability, but also powerful HE shells. Unfortunately even here they had to compensate the lack of quality with quantity - millimeters of the gun caliber. 122mm guns were necessary primarily to destroy fortifications providing low rate of fire due to a separate shell and powder charge.

The main problem for some of the participants in this discussion is that they have a firm belief that the usefulness of the tank as a weapon system is determined primarily by its ability to destroy enemy tanks. But the Soviets in World War II had different evaluation criteria due to different tactics of tank use. The Soviets had enough tanks and artillery, they lacked the experience to use these weapons wisely (e.g., using self-propelled artillery as tanks), whereas the Germans lacked the adequate AT artillery and used their tanks in the course of the war more and more often in the role of self-propelled AT units.

PS. The Soviets considered the Hetzer on the 38(t) chassis to be the most dangerous, this conclusion was drawn both in battlefield and testing reports. At the same time, the effectiveness of anti-tank self-propelled artillery units based on the Pz IV with a 75mm long-barreled gun was rated much lower. Reports noted that the excessive power of the powder charge (comparable to that of the Soviet 100mm cannons!) required thicker projectile sidewalls, precluding the feasibility of an effective high-explosive projectile, as well as the use of existing rounds.

 

[Elan Vital]

Since the turret ring diameter was limited - the Soviets didn't have a suitable machine for mass production of the turret rack with diameter exceeding 1500 mm until late 1943 (rather 1944), thus no any 76-mm gun with more powerful ammunition or any 85mm gun requiring a 1600mm turret rack could be mounted in the mass-produced T-34 until 1944. The Soviets were not able to provide the necessary production capacity of 1600mm turret racks earlier.

Yet both the T-28, KV and IS series employed a 1600mm turret ring or larger, factory #83 was said to have sufficient tooling for producing such a turret ring for T-34M. That the T-28 got this ring from the get go already shows that the T-34 could have been designed with a 1600mm turret ring from day one. Was this tooling lost in Barbarossa? Per Yuri Pasholok's article on the early T-43 in 1942, it was repeatedly asked to use a 1600 mm turret ring for the 3-man turret but Morozov's argument against it was the weight penalty, not production factors. It would seem strange to insist on this larger turret ring if it was impossible to produce in adequate numbers anyway.

 

[tomo pauk]

He relied upon the small size and quietness of his Valentines and the longer range Soviet mortar smoke rounds enabled him to take leaps into dead ground to flank Axis tanks and AT guns.

Hmm. Valentine armed with the Soviet 57mm gun = the best tank buster the Soviets never had?

 

[bf109xxl]

Yet both the T-28, KV and IS series employed a 1600mm turret ring or larger, factory #83 was said to have sufficient tooling for producing such a turret ring for T-34M. That the T-28 got this ring from the get go already shows that the T-34 could have been designed with a 1600mm turret ring from day one. Was this tooling lost in Barbarossa? Per Yuri Pasholok's article on the early T-43 in 1942, it was repeatedly asked to use a 1600 mm turret ring for the 3-man turret but Morozov's argument against it was the weight penalty, not production factors. It would seem strange to insist on this larger turret ring if it was impossible to produce in adequate numbers anyway.

1. Factory No.183 in Kharkov even had a machine for a turret rack with a diameter of 1750 mm, but Pasholok does not mention whether this machine could provide production in the required quantity - not 1940 and not even the beginning of 1941, but 1942! Taking into account the Soviet tradition of overestimating own capabilities, I think not.
2. The tooling could indeed have been lost during the evacuation of the plant.
3. I did not say that the Soviets could not produce tanks with a 1600mm turret ring at all, I said that they could not mass produce just the T-34 with such a turret until 1944. It is enough to compare the production volumes of these tanks. The Soviets received the machines for mass production of T-34s with 1600mm turret ring as part of the Lend-Lease program.
4.Apparently, Morozov realistically assessed the capabilities of the plant and tried his best to defend the small diameter of the turret ring, as he was afraid that too much tooling modification would be required, and this would inevitably reduce the rate of production - the chances of mass production were sharply reduced.

 

[bf109xxl]

Hmm. Valentine armed with the Soviet 57mm gun = the best tank buster the Soviets never had?

The Valentine didn't need a 57mm high ballistic gun - its major enemy was anti-tank artillery. And the low noise and low profile of light tanks and self-propelled artillery units (including the T-70 and SU-76) were noted by many veterans, who attached great importance to them. The T-34 could be heard from a long distance - it was a very noisy tank, but the noise of the Valentine and T-70 engines was comparable to the noise of a truck engine.
All the Soviets needed was an HE shell for the Valentine's gun!