British Army 'sanity options 2.0', 1935-43

[tomo pauk]

When you spoke of the 'recognised' need for "bigger guns and ability for both tank guns and AT guns to fire HE shells" it did seem that you were saying that tanks needed bigger guns, and that tank guns (big or small) needed to fire HE shells. If you say that tanks need bigger guns, and tank guns need to fire HE shells, then surely that is saying that tanks needed bigger guns (and with tanks that almost inevitably means high velocity) with HE.

I'm not sure what else you meant to say., unless it was that tanks needed big guns that could fire HE, but that these guns didn't need to be high velocity. In that case the British 3" CS weapon surely fits the bill.

The countries I was talking about have had the smaller guns also supplied with HE shells, as well as the 'proper' HE throwers, like what French had in the Char B, Soviets in BT-7A and T-38, and Germans in the Pz-IV.
The 3"CS fits the bill in theory - if it there was a doctrine for it firing the HE ammo, if there was a good number of tanks armed with CS guns, and if firing of the HE ammo was it's main role; however, neither was the case before 1940.

FWIW, the Sovier 45mm HE shell weighted 4.5 lbs.

Whatever the case, it seems that a need for bigger guns and tank guns with HE (of significant size) wasn't so apparent to the Russians, French and Germans that they did much more about it than the Brits did. None of them seemed to have provided their tanks with a larger proportion of big guns or a larger amount of guns with significant HE than the Brits did.

So if the need was so apparent to the Russians, Germans and French, why didn't they do more to give their own tanks bigger guns and effective HE shells? If the Brits were stupid to use a gun of around 40mm capacity and 60-100g of potential HE, then so was every other country.

Here you are mistaken. All of these countries have had tanks with decent HE shells in service, and were outfitting the smaller guns with HE shells, too. British did not, on both accounts. Other countries haven't left the potential for HE on the backburner for 7 years, but were buying both AP and HE shells for their tanks guns from day one, with French and Soviets introducing the guns with twice the HE load vs. the 2pdr.
Germans were also outfitting the 7.5cm guns with APHE shells for the Pz-IV.

More later.

 

[tomo pauk]

A few pages back, it was noted that the 6 pdr, compared to the 12 pdr, was lighter and easier to install in a tank. So if it w s said that reductions in weight and installation problems were positives for a 6 pdr over a 12 pdr, why are these same factors of reduced weight and installation problems not also positives for the 2 pdr over a 6 pdr?

Job of a tank gun is to destroy the enemy assets (tanks, infantry, artillery pieces, trucks, MG nests etc.) in the frontline and just behind it. A bigger gun is a better tool for this. Small gun is worse in this.

If weight and installation problems are not considerations, why stop at 6 pdrs? Wouldn't the Vickers 3-inch 20 CWT, aka the 3" 16 CWT A/T gun, be far superior with its muzzle velocity of 2,500 fps with the 12.5lb shell and range of 9,250 yards? Even the 13 pdr 9 CWT has better stats than the 6 pdr, which had a mere 1818 fps muzzle velocity even in the long version. So at what stage does one stop saying "just upgun it!!!!"????

Weight and installation problems are an issue if the gun is too big & powerful, especially if the turret design is dictated to feature the mantlet that protrudes inside of the turret ring (another consequence of preference to the too small tank guns in the 1930s), as it was the case in the British tank design*. The historical 6pdr 12cwt was easy to retrofit on the modest turrets of the existing British tanks, not the case with the big 3in 20cwt.

Switching from the low MV 6pdr of ww1 vintage to the low MV 3pdr is not upgunning it, it is downgunning it. Same with the adoption of the 2pdr.

*the thing that precluded installation of the 77mm HV on the Cromwell, as well as installation of the 17pdr on the Comet; that detail also kept the Churchill under-gunned; 'just upgunning it' was a problem for the mid-war British tanks

 

[Capt Thunderbolt]

FWIW, the Sovier 45mm HE shell weighted 4.5 lbs

The Soviets used long shell at lower velocity, giving around 1/3 to 1/2 more mass.

Other nations did not appear to follow.

 

[JasTysoe]

Job of a tank gun is to destroy the enemy assets (tanks, infantry, artillery pieces, trucks, MG nests etc.) in the frontline and just behind it. A bigger gun is a better tool for this. Small gun is worse in this.

But was that what many people thought in the time frame? Didn't people like Guderian and Fuller think that was a job for two different tanks, and didn't people like Liddell Hart say that a bigger gun was NOT a better tool? Yes, what they thought is not relevant in at ATL, but it IS relevant when it comes to discussing equipment choices that were made ITTL.

Weight and installation problems are an issue if the gun is too big & powerful, especially if the turret design is dictated to feature the mantlet that protrudes inside of the turret ring (another consequence of preference to the too small tank guns in the 1930s), as it was the case in the British tank design*. The historical 6pdr 12cwt was easy to retrofit on the modest turrets of the existing British tanks, not the case with the big 3in 20cwt.

That's also a truism, but earlier you said that going down from the 6 pdr to the 3 pdr was a mistake. That meant that the Vickers Medium would have had to fit a 7'4" 820-850lb QF 6 pdr Hotchkiss into a vehicle which didn't seem to have much spare space after fitting in the 6'2" 217lb 3 pdr. If they could fit a 850-lb gun into a 1920s vehicle, why not an 1100lb 3"er into a 1930s one? The point is that I'm just trying to find the line about where up-gunning becomes impractical, and whether that is consistent.

By the way, I'm not sure if "easy" was the term to use for fitting the 6 pdr into the Valentine etc.

Switching from the low MV 6pdr of ww1 vintage to the low MV 3pdr is not upgunning it, it is downgunning it. Same with the adoption of the 2pdr.

But the old 6 pdr had far inferior muzzle velocity to the 3 pdr, so it wasn't going to be able to kill tanks as the job description required. Although the 2pdr was smaller, as you said earlier "stipulating the caliber categories is that it is worth as much as stipulating the cubic displacement of the ww2 aero engines - apart from a column in the data sheet, it matters next to nothing to the men using it".

Since Gun A has inferior penetration and actual calibre is irrelevant, why is shifting to Gun B a downgrade?

*the thing that precluded installation of the 77mm HV on the Cromwell, as well as installation of the 17pdr on the Comet; that detail also kept the Churchill under-gunned; 'just upgunning it' was a problem for the mid-war British tanks

Sure, upgunning in WW2 was in reality very complicated because of certain design factors, but the question related to when one can stop saying in a AH thread "just make it bigger" or "just make it faster" or "just make it better" before it gets ASB-ish.

 

[tomo pauk]

But was that what many people thought in the time frame? Didn't people like Guderian and Fuller think that was a job for two different tanks, and didn't people like Liddell Hart say that a bigger gun was NOT a better tool? Yes, what they thought is not relevant in at ATL, but it IS relevant when it comes to discussing equipment choices that were made ITTL.

Bigger gun was a better tool, and it was known to be a better tool for decades before Fuller, Guderian or Hart wrote their 1st sentence about warfare.
I'd put far greater emphasis on what was done/achieved, than what someone thought. What was achieved in the continental armies was the existence of tanks capable for AP work and for HE work, usually in a single tank.
BTW, your words, my bold emphasis:

War experience showed that wouldn't work, and the fact that Hobart and Liddell Hart went off on such flights of fancy indicates that those who didn't follow their hype weren't all conservative - Liddell Hart and Hobart were simply wrong in many ways so it's understandable that they encountered opposition.

That's also a truism, but earlier you said that going down from the 6 pdr to the 3 pdr was a mistake. That meant that the Vickers Medium would have had to fit a 7'4" 820-850lb QF 6 pdr Hotchkiss into a vehicle which didn't seem to have much spare space after fitting in the 6'2" 217lb 3 pdr. If they could fit a 850-lb gun into a 1920s vehicle, why not an 1100lb 3"er into a 1930s one? The point is that I'm just trying to find the line about where up-gunning becomes impractical, and whether that is consistent.

By the way, I'm not sure if "easy" was the term to use for fitting the 6 pdr into the Valentine etc.

The 6pdr was actually installed into the Valentine, no such luck for the 12lb 20 cwt. 6 pdr was also installed on the later Crusaders.
Yes, going from 6pdr to 3 pdr was a mistake.
If the 6 pdr is carried over (hopefully the longer barreled type, not the short type), designers of the tank turret will be making a turret for it, not for the small 3 pdr.
Thing with the 12lb 20cwt gun was that, as-is, it was too big for the tanks' turrets of the 1930s, and it's recoil momentum will be much greater than that of the 6pdr. British managed to install the ordnance of the 20cwt in the semi-fixed mount on Churchill, their biggest tank in then-current production.

But the old 6 pdr had far inferior muzzle velocity to the 3 pdr, so it wasn't going to be able to kill tanks as the job description required. Although the 2pdr was smaller, as you said earlier "stipulating the caliber categories is that it is worth as much as stipulating the cubic displacement of the ww2 aero engines - apart from a column in the data sheet, it matters next to nothing to the men using it".

Since Gun A has inferior penetration and actual calibre is irrelevant, why is shifting to Gun B a downgrade?

HE performance is surely a downgrade, since the shell is now only one half of the weight than what the 6pdr was making. A thing made even worse with preference of the British Army that the 3pdr fires only the AP shot.
Yes, the old 6pdr was with the low MV. British Army can use the 6pdr Hotchkiss (MV was 1765 fps), as it was the case with the 1st MK.V tanks from ww1, and much improve the AP performance, even topping what the 40 cal 3pdr interwar gun was good for.

Sure, upgunning in WW2 was in reality very complicated because of certain design factors, but the question related to when one can stop saying in a AH thread "just make it bigger" or "just make it faster" or "just make it better" before it gets ASB-ish.

You can see that I'm trying to be rather conservative with my suggestions. Most of the guns I suggest to be used in the 1930s are ww1 left-overs.

 

[JasTysoe]

The countries I was talking about have had the smaller guns also supplied with HE shells, as well as the 'proper' HE throwers, like what French had in the Char B, Soviets in BT-7A and T-38, and Germans in the Pz-IV.
The 3"CS fits the bill in theory - if it there was a doctrine for it firing the HE ammo, if there was a good number of tanks armed with CS guns, and if firing of the HE ammo was it's main role; however, neither was the case before 1940.

FWIW, the Sovier 45mm HE shell weighted 4.5 lbs.



Here you are mistaken. All of these countries have had tanks with decent HE shells in service, and were outfitting the smaller guns with HE shells, too. British did not, on both accounts. Other countries haven't left the potential for HE on the backburner for 7 years, but were buying both AP and HE shells for their tanks guns from day one, with French and Soviets introducing the guns with twice the HE load vs. the 2pdr.
Germans were also outfitting the 7.5cm guns with APHE shells for the Pz-IV.

More later.

As noted earlier, those smaller guns normally carried very small amounts of HE and so the vast majority of Russian, French and German tanks don't appear to have had "decent" HE shells.

There were 155 BT7As produced, out of a total pre-war tank arm of 23,000. The T-38 had a 7.62mm machine gun, which wasn't a "proper" HE thrower. There were short barrelled howitzers in the 550 or so T-35 and T-28s. So that's about one in 30 tanks with a "proper" HE thrower.

The Germans had about 300 Pz IVs at the start of the war out of some 3000 tanks, so about one in 10 with a "proper" HE thrower. I think I gave the details of the French guns earlier and their proportion of tanks with decent HE capacity was probably closer to that of the Russians.

The British First Armoured Div went to France with about 10% of its tanks with a howitzer, and I think that was about the norm. The CS tanks eere meant to carry HE shells even though they were in short supply.

I'm not mistaken about the fact that other nations had HE for their small (C37-47mm) guns - I referred to that earlier. The point was that none of them had much HE and therefore were not very effective in that role.

The point is that in reality the Brits do not appear to have been as far behind as often claimed.

 

[yulzari1]

One should note that the pre war CS tank guns were almost entirely short barrel howitzers or similar. Fine if you can get up close and fine for smoke which can cope with less accuracy but lobbing effectively indirect fire HE shells from an uncertain position to another uncertain position using estimated ranges is not going to reliably hit a single entrenched post nor another tank. Especially if that tank is moving several times its own length during the flight of the lobbed shell. It was not until the tank guns went up to 75mm in direct fire velocities that enemy targets could be reliably hit using a fast flat trajectory.

What the pre war CS guns were for was closing upon a defended infantry position and throwing a 75mm HE round in from really close in. If they met an enemy tank at similar very close ranges they could make them very upset but better to leave it to the smaller calibre high speed hole punchers to hit them from a distance. This was exactly what the Australians and New Zealanders wanted done in the jungles with the 3.7” CS guns of the MatildaII and Valentine so it suited them but not a scenario applicable to Europe or North Africa..

What fast 75mm HE guns that were on the stocks pre war were naval and AA guns which had no need to worry about weight, size nor recoil length as they were not being fired from a glorified telephone box already filled with people. Once the decision was made to have 75mm tank guns dual use became workable. It was the baseline size for effective dual use. The French long ago did many studies on the minimum effective weight of HE and determined that a 75mm shell was the smallest up to the job. Hence the famous French 75 which thus kept down the weight of the gun and the logistics of it’s resupply.


Good luck pre war telling the Treasury that, yes we have assorted 3” guns indeed many sorts, but we want yet another one and no, it is likely too big and heavy to become the towed AT gun so we need that separately. From an AT point of view the 75mm dual purpose gun, at the time, was a solution to a problem that did not exist, nor was likely to for some time.

However, with hindsight, an early 6 Pounder could give the infantry a sound AT towed gun that was workable to dig in without major work and could be (no I would not want to be one of those doing it) manhandled and the same gun design, but with the chamber and bore of the QF 75mm, making a sound dual purpose tank gun. Pre war was the ideal time to be ordering the machinery to make the long barrel version.

 

[Aber]

Job of a tank gun is to destroy the enemy assets (tanks, infantry, artillery pieces, trucks, MG nests etc.) in the frontline and just behind it.

Can we break this down a little?

• Tanks; Agree - but needs a hole puncher
• Infantry; Disagree - infantry in the open are attacked better with a machine gun than single shot HE. Dug in infantry will be near invisible.
• Artillery pieces; Partially disagree - Single shot HE may be better in certain circumstances re field artillery, but anti-tank guns will be near invisible at combat ranges if properly sited.
• Trucks; Agree
• MG nests; Partially disagree - machine gun may be better than HE as can more easily walk onto a target which is near invisible at combat ranges

In particular British doctrine is focussed on infantry with artillery support; direct fire HE adds little to this, especially on a battlefield where defenders are hard to identify at combat ranges.

Where British doctrine breaks down is for deep penetration by armoured forces just consisting of tanks with no HE options.

 

[Cryhavoc101]

On the subject of 2 pounder - lack of HE effectiveness I have 3 things to add

Firstly the first role of a tank in 1940 was to destroy other tanks unless it was a specialised vehicle such as the CS tank etc and then even the Pz IV which was initially an infantry support tanks with a short 75mm had solid shot

Secondly British industry was flat out, producing 2 pounder 'solid' AP ammunition until 1942 when it gained the capacity for HE ammunition production - just as it was getting replaced with the 6 pounder in the tank estate

Thirdly - no one else was really running better than 2 pounder in their tank estates into 1942

• The Germans had 37mm
• The Russians had 45mm
• The Americans had 37mm
• The French had 37mm and 47mm (on the Somua S35)

 

[tomo pauk]

Firstly the first role of a tank in 1940 was to destroy other tanks unless it was a specialised vehicle such as the CS tank etc and then even the Pz IV which was initially an infantry support tanks with a short 75mm had solid shot

(my emphasis) - As declared by whom?
British tanks like Matilda I and Matilda II were literary called 'infantry tanks'. How was the Matlida I supposed to kill tanks is anyone's guess.
Pz-IV was firing both the HE and the solid shot.

Secondly British industry was flat out, producing 2 pounder 'solid' AP ammunition until 1942 when it gained the capacity for HE ammunition production - just as it was getting replaced with the 6 pounder in the tank estate

Unfortunately, that the 2pdr fired only the AP (APHE?) shot by late 1942 was a bug, not a feature.
Were there any experiments to retrofit the HE shells from the ww1 pom-pom 2pdrs, or the 40mm Bofors on the 2pdr AT & tank guns by 1940/41?

Thirdly - no one else was really running better than 2 pounder in their tank estates into 1942

• The Germans had 37mm
• The Russians had 45mm
• The Americans had 37mm
• The French had 37mm and 47mm (on the Somua S35)

Neither Soviets, nor Americans, nor Germans have gotten that memo. Not even the French.
They also never gotten the memo that smaller guns are not to be supplied with HE ammo.

 

[Capt Thunderbolt]

To all,

Regardless of what weapon you choose, the ammunition has to fit within the bounds of the turret and hull.

57mm from WW1 tanks is a lot shorter than any WW2 shot.

47mm 3 PDR is a lot closer to 2pdr

 

[Cryhavoc101]

(my emphasis) - As declared by whom?
British tanks like Matilda I and Matilda II were literary called 'infantry tanks'. How was the Matlida I supposed to kill tanks is anyone's guess.
Pz-IV was firing both the HE and the solid shot.



Unfortunately, that the 2pdr fired only the AP (APHE?) shot by late 1942 was a bug, not a feature.
Were there any experiments to retrofit the HE shells from the ww1 pom-pom 2pdrs, or the 40mm Bofors on the 2pdr AT & tank guns by 1940/41?


Neither Soviets, nor Americans, nor Germans have gotten that memo. Not even the French.
They also never gotten the memo that smaller guns are not to be supplied with HE ammo.

Infantry Tank is simply a tank that is designed to keep up with Infantry not attack infantry per se - and so had heavy armour and slow speed.

So with the exception of the 140 odd obsolete when built Matilda I (which was only liked by the Treasury and where arguably tankettes and not tanks) of which 77 went to France and remained there all other Infantry tanks had the 2 pounder or the 6 pounder or (later Valentines and Churchills) the 75mm.

There was also the MK VI light tanks which were but again pre war penny pinching and by 1939 the Army did not want light tanks anymore - it was again a tank liked only by the Treasury and the army went to war with what it had and it was pretty much used as a cavalry tank.

And we have the Legacy Italian L33s (which made up 9 of the Italian Army's 11 Tank battalions during Compass) and German Pz I and II - all equipped with Machine guns and autocannon

So I concede the point but lets agree that those tanks were pretty much all considered obsolete by 1940 and not really gun tanks and represented after 1940 a very small % of the various armies tank estates.

Again (with the exception of the legacy Light tanks and tankettes) what were the majority of 'proper' front line tanks armed with during the battle of France?

The Cruisers and Matilda II - 2 pounder
The French mediums? - 37mm and 47mm
The Germans Pz III and Czech tanks 37mm
The Italian MII/39 - 37mm

All of those tanks were pretty much armed with what was primarily an anti tank gun regardless if it had HE shells or not with all of the HE shells having little better than a hand grenade worth of HE content (63 grams) with perhaps mid war Russian 45mm HE shells having perhaps twice that.

As for Mygyvering up HE shells for the 2 pounder - I am not aware of any!

Given the Trade union nature of the Desert Army into 1942 I doubt it?

Bofors was pretty much brand new and suspect any ammo produced was going to those RA units equipped with it.

The Pom Pom again was Navy so I don't expect there was much opportunity to get hold of any that ammo for experiments in the field

I know the forces fighting in the Pacific campaign did knock some up but that was more likely a supply issue as 2 Pounder HE was in production then

Again my under standing of the lack of 2 pounder HE was production limitations - there was one company making it and due to panzer fever after the fall of France it was flat out producing AP only into 1942.

There is some confusing data on pre battle of France 'APHE' but the best description I have heard of that was a Solid shot with a very small 'burster' explosive content designed to set fire to any tank hit - a bit like a Naval AP shell. But the shell/fuse was deemed unreliable, more difficult to produce than pure solid shot and so was binned off and production limited to solid AP.

However one source I saw suggested that this was also based on after battle reports from France where the APHE performed poorly but post Beda Fomm (6th Feb 41) it was found that M13 Tanks hit by APHE from 2 RTR Crusiers almost always resulted in the entire crew being killed when APHE ammunition was used and tests after the battle confirmed this

Taken from WO.169/952 A.F.V. G.H.Q. MEF War Diary 1941

The question has arisen as to what, if any proportion of 2-pdr ammunition is to be A.P. HE.
Resulting from inspection of Italian M.13 Tanks after the BEDA FOMM action, and the remarkable number of Tanks found with the whole crew dead after a single hit by a 2-pdr. shell, a trial was held by 2 R.Tanks. At this trial the 2-pdr. H.E. Shell entered the M.13 Tank through the front plate and splinters were found in all sandbags which had been placed to represent the crew in position. The range was 900 yards.
It is realised that the German armour plate is of better quality than the Italian. But it is felt that if the H.E. Shell would penetrate the German tanks at say – 600 yards or less, it would be worth having a proportion of H.E. Shell to be used at the Tank commander’s discretion, to administer a “Coup de Grace” at short range.
The War Office have stopped production of 2-pdr. H.E. at home as a result of poor reports of its penetration power in FRANCE. We do not know, however, at what range it was used.
We would like to have your opinion as to whether in the light of an experience in the M.E. representations should be made to the War Office for renewed production.

Brigadier, General Staff
for D.C.G.S.
AFV.
HJ/MF
Copy to: – HQ., 7 Armd. Div.

So my understanding is that it was not a real HE round and it was not until later in 42 and 43 that we start to see any production of a True HE shell - and that would make sense as British production had really hit its stride by 42 and Britain was no longer in 'invasion panic mode' and while the 6 pounder was taking over there was still a large estate of 2 pounder armed tanks and armoured cars.

The Americans as I understand it were not making 37mm HE (or Cannister) until Feb 42 (April 42) with both rounds first used in anger at Alligator Creek by the USMC and possibly by the British during teh Desert battles of 1942 - I had a great web source for US ammunition production in WW2 but sadly the site no longer works last time I tried.

I know by mid war the Russian 45mm HE shell used a much larger shell that extended into the case with a 3rd of the propellent compared to the AP round but I am not sure if that existed early war?

However this was clearly the way to go

I understand that even late war the initial 17 pounder HE shells were considered not as effective as 75mm HE due to them having thicker shell walls and lesser explosive and being fired at the same velocity as the AP rounds in order to keep the sights simpler resulted in the shells burying into the ground more before exploding.

Anyway not sure what ammunition the Germans used early war in their 37s or the French?

And if they did have a proper HE round it is very likely to have a rather pathetic HE content - but perhaps better than nothing?

 

[Father Maryland]

How about a jury rig fix for the 2 Pounder. Namely taking older tanks and switching out the 2 pounder AT gun turret with a casemate assault gun type mounting a howitzer or something. So mix up the 2 pounder AT gun tanks with a cheap way of reusing older models that allows for a lot of common logistical support.

 

[CaptainCalvert]

How about a jury rig fix for the 2 Pounder. Namely taking older tanks and switching out the 2 pounder AT gun turret with a casemate assault gun type mounting a howitzer or something. So mix up the 2 pounder AT gun tanks with a cheap way of reusing older models that allows for a lot of common logistical support.

Up to Vals and Matildas (and possibly Crusaders) you could swap out the 2pounder for a 3" CS gun. That has the advantage of using the same tank and turret, with few other changes (onviously the ammo racks). That should be faster and more versatile than building a specialist assault gun since it's basically the same vehicle with a few replacement 3" guns. The Val and Matilda are already well armoured enough.

 

[tomo pauk]

Infantry Tank is simply a tank that is designed to keep up with Infantry not attack infantry per se - and so had heavy armour and slow speed.
So with the exception of the 140 odd obsolete when built Matilda I (which was only liked by the Treasury and where arguably tankettes and not tanks) of which 77 went to France and remained there all other Infantry tanks had the 2 pounder or the 6 pounder or (later Valentines and Churchills) the 75mm.
There was also the MK VI light tanks which were but again pre war penny pinching and by 1939 the Army did not want light tanks anymore - it was again a tank liked only by the Treasury and the army went to war with what it had and it was pretty much used as a cavalry tank.

Yes, 'infantry tank' was sorta description of the role (~ tank that supports infantry), not a description of the intended target. Supporting infantry meant attacking/silencing light field fortifications, attacking enemy infantry when possible, taking out the light guns the enemy is bound to have, as well as stopping enemy tanks; the list is certainly lacking several items. Unfortunately, as you've said, too many British tanks were MG-only, and these with cannons were not sporting HE ammo to make themselves viable when attacking no-tank types of targets.

So I concede the point but lets agree that those tanks were pretty much all considered obsolete by 1940 and not really gun tanks and represented after 1940 a very small % of the various armies tank estates.
Again (with the exception of the legacy Light tanks and tankettes) what were the majority of 'proper' front line tanks armed with during the battle of France?
The Cruisers and Matilda II - 2 pounder
The French mediums? - 37mm and 47mm
The Germans Pz III and Czech tanks 37mm
The Italian MII/39 - 37mm

In the post above, you were specifying the "until 1942" time frame. That includes 1941, when Germans were fielding 5cm guns on their Pz-IIIs, and production of Pz-IV was much increased (still much better HE thrower than a hole puncher). Soviets introduced the 76mm gun on the T-34 and KV-1, and Americans introduced 75mm gun on the M3 medium tank.

French 37mm guns were hopeless in destroying proper tanks (the cheap and not cheerful R35 was incapable of destroying another R35); guns were outfitted with HE ammo all the way. The 47mm were much better, especially in the AP ability.
I'm not sure why you've skipped the 75mm howitzer on the Char B? Hopeless against tanks ( bar a very lucky shot and a light opponent), main role being HE thrower.
I also don't know why the Pz-IV is not on your list.
All of the guns listed there were outfitted with HE shells, apart from British tanks.

Bofors was pretty much brand new and suspect any ammo produced was going to those RA units equipped with it.
The Pom Pom again was Navy so I don't expect there was much opportunity to get hold of any that ammo for experiments in the field
I know the forces fighting in the Pacific campaign did knock some up but that was more likely a supply issue as 2 Pounder HE was in production then
Again my under standing of the lack of 2 pounder HE was production limitations - there was one company making it and due to panzer fever after the fall of France it was flat out producing AP only into 1942.

RN was switching over from the low-velocity pom-pom to the high-velocity version, the HV version featuring a lighter shell and more propellant for the greater MV. Making the existing LV pom-pom shells surplus to the requirement?
I don't think that same factory was making HE shells for the 2 pounder (which one?) and AP shorts. If the case was that there was no alternative factory to make HE shells (or even the AP shots) for the 2pdr AT and tank gun by 1939, someone (or more of them) were deserving to grease gallows.

Taken from WO.169/952 A.F.V. G.H.Q. MEF War Diary 1941

Thank you for the transcript.

Anyway not sure what ammunition the Germans used early war in their 37s or the French?
And if they did have a proper HE round it is very likely to have a rather pathetic HE content - but perhaps better than nothing?

Both used mix of HE and AP; neither were that wonderful (especially the French 37mm AP), but indeed they at least had the HE shells
French, Czech/German or Austrian/Italian 47mm HE shell should be offering double the HE contents when compared with what the 37mm HE shells used.

 

[JasTysoe]

Bigger gun was a better tool, and it was known to be a better tool for decades before Fuller, Guderian or Hart wrote their 1st sentence about warfare.

We all know that in fact a bigger gun wasn't NOT a better tool per se. As we all know, a gun's effectiveness is a complex matter including rate of fire, accuracy, velocity, shell quality, barrel life and many other factors, and to try to pretend that it's simplistic as "bigger is better" doesn't do anyone any favours.

The low-velocity 3 pdr on the Vickers Medium wasn't a better tool than the 2 pdr. The Vickers "pom pom" had the same calibre as a Bofors 40mm but it wasn't its equal as a tool. A 12 guage shotgun isn't a better tool in many ways than a .303. The British 6" howitzer was not a better tool than the 5.5 inch that replaced it.

I'd put far greater emphasis on what was done/achieved, than what someone thought. What was achieved in the continental armies was the existence of tanks capable for AP work and for HE work, usually in a single tank.

That's not the point, but let's look at "what was done". "What was done" was;

* up until the T34 arrived (ie years after the British created their pre-war tanks and tank guns) the Russians equipped some 14500 of their tanks with 37 or 45mm guns (not 45-57mm) and with only moderate AP and very small amounts of HE filler. As far as I can find out, they also had about 6300 or more only armed with mgs at the start of WW2, a mere 150 BT7As and a tiny number of modified T26s, and 2500 heavies. So about 30% of their tanks just had mgs. The only medium tanks with "proper" HE and AP capacity you mention were the BT7As and T 26s which comprised about 1.1% of the Russian tank fleet - hardly evidence that they saw a great need for a medium tank with "proper" HE.

EDIT TO GIVE MORE DETAILS. The 76 mm KT tank gun model 1927/32 used in the T-28, T-35, the rare BT-7A and the equally rare T-26 "artillery tank" had a MV of only 387 m/s, so it wasn't a gun "capable of HE and AP" in any realistic sense. David Porter in "Soviet Tank Units 1939-45" states that the BT-7A's 76mm was "far more effective against AT guns or field defences than the 45mm (1.8 inch) guns of the standard BT tanks". So here we see that even when you give a 45mm gun HE, it's not very effective.


* the French had about 3000 tanks by the time France was invaded. Most of the light tanks had the 37mm SA/18, which had fairly poor A/T capacity and a tiny 30g of HE filler. The 37mm SA 38 had just 60g filler - ie the same as a hand grenade or the 2 pdr HE shell, and therefore in the words of David Fletcher "hardly worth considering". Other light tanks had the old 37s etc which had very poor AP capacity. So out of 2000 French tanks around when the 2 pdr was created, it seem that were none that were capable of effective AP and HE work.

Later, there were some 400 S35s and 400 Char B1s with the 47mm, which had good A/T capacity and 142g of filler, but that gun was created after the 2 pdr was so it's no evidence that the need for a larger gun should have been obvious when the 2pdr was created.

* EDITED TO GIVE MORE DETAILS. At the start of the war the German tank divisions were said to have 973 Pz 1; 1127 Pz II; 87 Pz III; and 198 Pz IV, plus 177 Czech tanks (which seem to have hd very light HE rounds even by the standards of 37mms) . So 82% of German tanks were armed with automatic weapons only; fewer than 10% had a decent-sized HE round, and a tiny 3% had a high-velocity gun that could also throw a (very small) amount of HE. It looks like the Germans were idiots too.

So "what was done" in other armies was actually not that different to what the British at the time they created the 2pdr. No nation fitted their tanks with 45-57mm weapons with good HE and AP capacity, as you think they should have done,. This was not because just about everyone involved in armour development in the relevant period was a moron - it was done because the future is a lot harder to predict than history is to read, and actually building things is a lot harder than criticising people for not building them.

In an ideal world, the Brits would have had better HE, but that would have involved sacrificing some other aspect of their tanks in order to gain an amount of HE that was "hardly worth considering". To assume that the trade-off they made was obviously wrong at the time is not correct on the evidence. In fact, I notice that you haven't provided any actual evidence to back up your premise that the small/medium HV guns of the period were effective when using HE. They may well have been very useful, but so far you have given no proof of that.

BTW, your words, my bold emphasis:

War experience showed that wouldn't work, and the fact that Hobart and Liddell Hart went off on such flights of fancy indicates that those who didn't follow their hype weren't all conservative - Liddell Hart and Hobart were simply wrong in many ways so it's understandable that they encountered opposition.

The point was that the fact that visionaries like Hobart and Liddell Hart, and everyone else, were so very wrong indicates that it is far, far harder to be correct about foreseeing the future than you appear to think. It's easy to look back and use hindsight - anyone can do that. Actually making accurate predictions about such things is incomparably harder than you appear to believe.

Oh, and many of those who made the decisions IOTL were, unlike you, actually working off real experience. For example, the decision to build a 2 pdr with fast traverse and tanks that fired smoke looks very sensible when actual experience not long before had shown that "field guns were, at that time, badly handicapped as to the number of tanks they could deal with by not having the wider traverse embodied in the latest type of mounting. In addition, the use of smoke enabled the attacking tanks to arrive almost on top of their objectives before being observed." The same author (Captain G. L. Kaye, M.C., R.F.A) that the 18 pdr Mk IV could achieve all-round fire on "the Vickers platform" which made it "superior at short ranges, when lateral movement of the target becomes greatly accentuated" although the Mk V was superior in general. Experience had shown that in tank warfare "The tank will appear anywhere and at any moment. Hence, an all-round field of fire and lightning handling are essential for the gun after a rapid move to the threatened spot." (my emphasis)

So the decisions to get a Vickers-built carriage that allowed 360 traverse for an A/T gun (when suitable) and to use smoke were not born out of extravagence or an ignorance of the downsides - it was born from the experience of people who actually done this stuff, and their appreciation of the fast-moving nature of armoured warfare. The same author, by the way, advocated for 18 pdrs to be mounted on tracks and given armour so they could become tank destroyers - that was a pretty good prediction for 1924. Yes, in the end the face of warfare and the capabilities and sizes weapons changed so that the intelligent decisions to use smoke and full traverse were no longer as important as other factors - but the fact that we know that does not justify sneering at those who did not have the luxury of hindsight.

By the way, US tests found that the 6 pdr's split trail, which you advocated, lead to the gun bouncing during recoil, causing difficulties with gun laying. Again, the experience of people who actually used this stuff runs contrary to your implications that those who were there at the time got it wrong and you get it right.

The 6pdr was actually installed into the Valentine, no such luck for the 12lb 20 cwt. 6 pdr was also installed on the later Crusaders.
Yes, going from 6pdr to 3 pdr was a mistake.
If the 6 pdr is carried over (hopefully the longer barreled type, not the short type), designers of the tank turret will be making a turret for it, not for the small 3 pdr.

So without getting ASBs to throw large bundles of pound bills into the Treasury, where does the money to make the bigger turret and the tank that can handle the bigger gun and turret come from? The British were short of money in the '20s and early to mid '30s. One cannot criticise them for not spending money they did not have.

Thing with the 12lb 20cwt gun was that, as-is, it was too big for the tanks' turrets of the 1930s, and it's recoil momentum will be much greater than that of the 6pdr. British managed to install the ordnance of the 20cwt in the semi-fixed mount on Churchill, their biggest tank in then-current production.

Yes, but you just changed the size of tank turrets to fit the 6 pdr, as quoted above. So once the ABSs have arrived and the money and resources have been found to mount a long 6 pdr (which is what you wanted) why not make it a 12 pdr? In fact why not make a Centurion?

 

[Capt Thunderbolt]

RN was switching over from the low-velocity pom-pom to the high-velocity version, the HV version featuring a lighter shell and more propellant for the greater MV. Making the existing LV pom-pom shells surplus to the requirement

The later 2-pdr Mark VIII guns and mountings used the same HE projectiles (now known as the "LV Type") but to the best of my knowledge they were not equipped with fuze setters. Existing LV rounds still in stock were used up during the war. New production of LV Type and later HV Type projectiles used standard impact fuzes such as the Fuze No 243 Mark IIN shown in the Additional Pictures section on the 2-pdr. Mark VIII datapage

Britain 2-pdr [4 cm/39 (1.575")] QF Mark II, Mark II* and Mark II*C - NavWeaps

www.navweaps.com

 

[Capt Thunderbolt]

In the post above, you were specifying the "until 1942" time frame. That includes 1941, when Germans were fielding 5cm guns on their Pz-IIIs, and production of Pz-IV was much increased (still much better HE thrower than a hole puncher).

Origins
The Panzer IV was the brainchild of the German general and innovative armoured warfare theorist Heinz Guderian.[7] In concept, it was intended to be a support tank for use against enemy anti-tank guns and fortifications.[8] Ideally, each tank battalion in a panzer division was to have three medium companies of Panzer IIIs and one heavy company of Panzer IVs.[9] On 11 January 1934, the German army wrote the specifications for a "medium tractor", and issued them to a number of defense companies. To support the Panzer III, which would be armed with a 37-millimetre (1.46 in) anti-tank gun, the new vehicle would have a short-barreled, howitzer-like 75-millimetre (2.95 in) as its main gun, and was allotted a weight limit of 24 tonnes (26.46 short tons). Development was carried out under the name Begleitwagen ("accompanying vehicle"),[10] or BW, to disguise its actual purpose, given that Germany was still theoretically bound by the Treaty of Versailles ban on tanks.[11]