I'm temped to say do that in the 30's using the 3.7" mountain Howitzer and issue a battery to each infantry battalion for direct infantry fire support,
Rearm the British Infantry for WWII
- Thread starter Peg Leg Pom
- Start date
While not a terrible idea on the surface and in some ways a good Idea I wouldn't do it. The biggest advantage of the 2 pounder for me is it's small size and light weight so its good for the far east until the end of the war. Mating the 2pounder to take the Bofors barrel will give it a bit more performance but not enough to increase its useful life in the west whilst making it less useful in the east.
You can start 6 pdr at any time. The main problem is it take 6 times the effort, time and materials.
Any bigger weapon will be a trade off btw size and numbers.
In the real world 6 pdr was rapidly superseded by boring it out to 75mm. Is there any advantage in adopting 6pdr or go straight to 3” gun?
The 6pdr was rapidly superseded as a tank gun due to the post Dunkirk panic putting Britain 1/2 a generation behind the trend in tank development. Get it into production before the all of France and that is avoided.
marathag
Banned
The 25mm was really portable, the 2 pdr AT carriage was huge and complex. The 25mm Hotchkiss was 700 pounds lighter than the 2 pdr.
Cheaper, too. Quantity has a quality of its own, after all.
As PLP mentioned the 6 pounder was delayed by Dunkirk meaning its service life was effectively halved as a tank gun. Add to that you have a lot of lend lease tanks with US 75mm guns and plenty of that Ammo going to the British so standardising on it makes sense. Even then it was less effective at knocking out tanks and was only used as a tank gun.
The main benefit of going for a 6 pounder is that it is also a very good AT gun. As an AT gun the 6 pounder was used right until the end of the war, that's a capability you don't want to loose. A 3" gun will do the job as well yes but will be a lot larger, heavier and more cumbersome. That being said in another thread someone mentioned the Vickers 75mm AA gun as a good tank gun and I kind of agree.
Get working on the 6 pounder and get it in a tank fast. If that tank can take the 75 then do it, if not make a bigger tank.
Not if it cant do the Job. By 41 German tanks are armoured past its capability. Yes it has some usefulness in 1940, especially against panzer 1's and 2's where it is leathal. Thing is why are you making decisions for 1940, France is going to fall despite what the British are doing. I'm more concerned about planning for post Dunkirk so things that where delayed should be started pre fall of France etc.
marathag
Banned
But they would be buying the 25mm in 1935, when tanks were mostly made of thick tinfoil.
Each regiment well equipped with 25mm pulled or in portee mount on a Carrier beats a 2 pdr AT that few troops even saw
OTL yes, buying the 25mm as a stop gap made sense due to shortages of 2 pounders. Getting sufficient made pre war would be a useful change. I don't see the point in spending money on a weapon for use in 1940 only when that money can be better spent on getting equipment ready for the whole war. Worst case scenario beg, borrow and steal 25mm's of the French.
Having more projectiles bouncing off armour they can't penetrate isn't really much use though, no matter how light the gun might be.
If we can get them something better then yes. As it is it could be useful for anti-material work but that hadn't been envisaged yet. Beyond that convert it to a GRB 39 type weapon with heat and HE grenades and it's good for a while.
The Birch gun had the ability to raise its QF 18-pounder gun almost 90 degrees to give it a secondary anti-aircraft ability, seems like a decent starting point. During the war the British did build some self-propelled anti-aircraft guns (SPAAG) based on the Light Tank Mk VI with the AA Mk I mounting four Besa 15 mm machine guns and the Crusader with the AA Mk I which mounted a Bofors 40 mm gun and AA Mk II/Mk III which mounted two or three Oerlikon 20 mm guns, the Canadians built the Skink which was a Grizzly tank with the turret mounting four Polsten 20 mm guns, so it's not impossible to do something like that if they have the impetus.
Sounds rather like the towed triple Polsten anti-aircraft mounting which can be seen photographed on the page.
IIRC the chap who designed the 6-pounder was declined when he first suggested it – somewhat understandable as the 2-pounder was more than adequate against anything being fielded at the time, when they looked at it some time later a shortage of draughtsmen blocked its development, and then following the evacuation from Dunkirk they didn't want to swap over production from the 2-pounder as it was a gap in production. If you want it sooner then you either need to find some way to get it development started when first proposed, have more draughtsmen on staff so there isn't a shortage, or have more anti-tank guns successfully evacuated from the continent.
The Boys is good enough to kill light armour and give an infantry company something that will hurt vehicles attacking them. If anything heavier than an armoured car or light tank appears they can retire onto battalion where the 2pdrs can (hopefully) cover them.
The 25mm is ok but if it can't kill a tank and you don't have anything better then your battalion is dead the first time a tank appears in front of them. The 2pdr might well be heavier but it's a hell of a lot easier to transport for the British Army (since it can be towed by any light vehicle with the appropriate tow hitch that you happen to have lying around the MT) and it'll kill anything the British Army is likely to face through to 1941 (and in an ideal world you'll be replacing it by mid 1940 with a 6pdr that can be relied on to kill pretty much anything short of a big cat up to the end of the war).
marathag
Banned
25 mm anti-tank gun model 1934, Canon 25 mm S.A. Mle 1934.
Its story begins before the end of WWI, when the well known Hotchkiss company began designing a new tank gun. Since the war ended, the project was mothballed, but suddenly came up again in the early 1930s, when the French army was looking for a new anti-tank gun. By putting the failed anti-tank gun on a wheeled mount with deployable trails and a small shield, the company ended up with a small and cheap anti-tank gun, and a decent one at that. The prototype, produced in 1933, successfully passed trials. The gun was accepted into service as the Canon 25 mm S.A. Mle 1934, or 25 mm semi-automatic gun, model 1934. Hotchkiss received their first order for 200 units in 1934.
Design specifications
Compared to its field artillery "sisters", the 25 mm anti-tank gun looked like a toy due to its small size and mass. Its designers took a number of steps to make the gun easier to hide on the battlefield. The top of the gun shield was wavy (straight lines are easier to see) and the barrel was equipped with a flash suppressor. The gun was semiautomatic: the breech remained open after a shot was fired and extracted the shell, but closing the breech had to be done manually.
The Hotchkiss gun was anti-tank, and only that. Its ammunition consisted of two kinds of armour piercing shells: one with a tracer, and one without. A tracer shell (its tip was painted green) made it easier for the gunner to correct his fire, but in some cases, like when fighting from an ambush, it risked revealing the position of the gun. In that case, a tracerless shell could be used (black tip).
The ammunition design was similar to an enlarged anti-tank rifle round: it has no explosive filler and consisted only of steel shot. The mass of the shot was 317 g (320 g for the tracer variant), and the length was 109 mm. The gunpowder in a large 145 mm long casing gave it a muzzle velocity of 920 m/s. According to French data, the cannon could penetrate 40 mm of armour at 30 degrees from 400 meters. The report on Soviet trials of the captured weapon is less optimistic: at the same angle, it gave the gun 36 mm of penetration at 100 meters, 32 at 300, 29 at 500, and 22 at 1000.
The small caliber and semiautomatic breech gave the gun a high rate of fire. French manuals describe it as 20 RPM, but other sources say 15 RPM against moving targets or 25 RPM against stationary ones. A well trained crew could fire 35 times per minute. Of course, in that case, no fire correction was possible.
The gun was equipped with a telescopic 4x sight with a FOV of 11 degrees. The distance markings on the sight went up to 3500 m. A backup iron sight, consisting of a bead and a rear sight, was installed on top of the telescopic sight. It could be adjusted to four positions: 400, 600, 800, and 1000 meters.
Aside from the wavy top, the gun shield had another feature: a large portion of the surface was protected by two additional shields. The mount had deployable trails and two wheels with pneumatic tires. Thanks to the gun's low mass (475 kg), it could easily be moved around the battlefield by its crew of 6. Special straps came with the gun for that purpose. The gun was to be moved by prime movers over long distances, but practice showed that the design was too delicate. The top speed had to be limited to 15 kph off-road and 30 kph on a highway. An attempt to solve this problem resulted in a stop-gap solution: a special trailer with sprung wheels that would carry the gun. This technique, often used with obsolete guns, seemed absurd when applied to a new gun specifically designed to be transported by motor transport. Nevertheless, this method was widespread. Another way to improve mobility was carrying the gun in the truck bed.
The gun's light weight allowed the crew to move it on their own.
Vauvillier F. Le Canon de 25 mm antichar modele 1934 Hotchkiss
A new version of the gun appeared in 1937, Canon 25 mm S.A.-L Mle 1937 (L for leger, light), designed by Puteaux. This gun weighed only 310 kg. Visually, it could be distinguished by a different shape of the shield and flash suppressor. The breech and trigger mechanism were also modified to increase the rate of fire.
In total, 4225 units of Canon 25 mm S.A. Mle 1934 and 1285 Canon 25 mm S.A.-L Mle 1937 were built before May 1st, 1940. The more powerful Canon 37 mm S.A. Mle 1937 was supposed to replace the 25 mm anti-tank guns, but its production was ramping up slowly. Another attempt was made to modernize the gun in 1939. The result, named Canon 25 mm S.A. Mle 1934 modifie 1939 (25 mm semi-automatic gun model 1934 modification 1939), received a more robust mount, which removed the speed limit for towing. The army ordered 1200 of these guns, and supplies were scheduled to start in June of 1940. It's not known whether or not the first batch of guns was ever delivered to the customer.
www.tankarchives.ca
Its story begins before the end of WWI, when the well known Hotchkiss company began designing a new tank gun. Since the war ended, the project was mothballed, but suddenly came up again in the early 1930s, when the French army was looking for a new anti-tank gun. By putting the failed anti-tank gun on a wheeled mount with deployable trails and a small shield, the company ended up with a small and cheap anti-tank gun, and a decent one at that. The prototype, produced in 1933, successfully passed trials. The gun was accepted into service as the Canon 25 mm S.A. Mle 1934, or 25 mm semi-automatic gun, model 1934. Hotchkiss received their first order for 200 units in 1934.
Design specifications
Compared to its field artillery "sisters", the 25 mm anti-tank gun looked like a toy due to its small size and mass. Its designers took a number of steps to make the gun easier to hide on the battlefield. The top of the gun shield was wavy (straight lines are easier to see) and the barrel was equipped with a flash suppressor. The gun was semiautomatic: the breech remained open after a shot was fired and extracted the shell, but closing the breech had to be done manually.
The Hotchkiss gun was anti-tank, and only that. Its ammunition consisted of two kinds of armour piercing shells: one with a tracer, and one without. A tracer shell (its tip was painted green) made it easier for the gunner to correct his fire, but in some cases, like when fighting from an ambush, it risked revealing the position of the gun. In that case, a tracerless shell could be used (black tip).
The ammunition design was similar to an enlarged anti-tank rifle round: it has no explosive filler and consisted only of steel shot. The mass of the shot was 317 g (320 g for the tracer variant), and the length was 109 mm. The gunpowder in a large 145 mm long casing gave it a muzzle velocity of 920 m/s. According to French data, the cannon could penetrate 40 mm of armour at 30 degrees from 400 meters. The report on Soviet trials of the captured weapon is less optimistic: at the same angle, it gave the gun 36 mm of penetration at 100 meters, 32 at 300, 29 at 500, and 22 at 1000.
The small caliber and semiautomatic breech gave the gun a high rate of fire. French manuals describe it as 20 RPM, but other sources say 15 RPM against moving targets or 25 RPM against stationary ones. A well trained crew could fire 35 times per minute. Of course, in that case, no fire correction was possible.
The gun was equipped with a telescopic 4x sight with a FOV of 11 degrees. The distance markings on the sight went up to 3500 m. A backup iron sight, consisting of a bead and a rear sight, was installed on top of the telescopic sight. It could be adjusted to four positions: 400, 600, 800, and 1000 meters.
Aside from the wavy top, the gun shield had another feature: a large portion of the surface was protected by two additional shields. The mount had deployable trails and two wheels with pneumatic tires. Thanks to the gun's low mass (475 kg), it could easily be moved around the battlefield by its crew of 6. Special straps came with the gun for that purpose. The gun was to be moved by prime movers over long distances, but practice showed that the design was too delicate. The top speed had to be limited to 15 kph off-road and 30 kph on a highway. An attempt to solve this problem resulted in a stop-gap solution: a special trailer with sprung wheels that would carry the gun. This technique, often used with obsolete guns, seemed absurd when applied to a new gun specifically designed to be transported by motor transport. Nevertheless, this method was widespread. Another way to improve mobility was carrying the gun in the truck bed.
The gun's light weight allowed the crew to move it on their own.
Vauvillier F. Le Canon de 25 mm antichar modele 1934 Hotchkiss
A new version of the gun appeared in 1937, Canon 25 mm S.A.-L Mle 1937 (L for leger, light), designed by Puteaux. This gun weighed only 310 kg. Visually, it could be distinguished by a different shape of the shield and flash suppressor. The breech and trigger mechanism were also modified to increase the rate of fire.
In total, 4225 units of Canon 25 mm S.A. Mle 1934 and 1285 Canon 25 mm S.A.-L Mle 1937 were built before May 1st, 1940. The more powerful Canon 37 mm S.A. Mle 1937 was supposed to replace the 25 mm anti-tank guns, but its production was ramping up slowly. Another attempt was made to modernize the gun in 1939. The result, named Canon 25 mm S.A. Mle 1934 modifie 1939 (25 mm semi-automatic gun model 1934 modification 1939), received a more robust mount, which removed the speed limit for towing. The army ordered 1200 of these guns, and supplies were scheduled to start in June of 1940. It's not known whether or not the first batch of guns was ever delivered to the customer.
Canon 25 mm S.A. Mle 1934: A "Baby" Gun for a Grown Up War
A blog about World War II era archive documents, primarily dealing with armoured warfare.
So basically it was pretty good in 1940, Most German tanks at 300m and the Panzer 1's and 2's are toast. From 1941 though when panzer armour gets into the 50mm range you're in real trouble with it.
Compare that to the 2 pounder
| Distance | 100 Yards | 500 Yards | 1000 Yards | 1500 Yards |
| AP | 49 | 37 | 27 | 17 |
| APHV | 62 | 57 | 38 | 28 |
| APCBC | 75 | 65 | 57 | 49 |
Even with Base ammo it stands a chance in 41 and post 42 is ok against all but the latest marks of Panzer 3' and 4's front armour but still penetrating side and rear armour.
marathag
Banned
2 pdr had problems with Shot shattering on hitting German Face Hardened armor, that on paper, should have been easy penetrations.
This lasted through much of 1941, when capped AP finally showed in decent amounts
Also, much Soviet Armor was far harder than rolled homogenous German plates or US cast or rolled homogenous,
Sov 495 BN vs Ger 257-310 or US cast 200-230/rolled 280/320
That extra hardness would resist non capped projectiles better, but at the risk of spalling for non penetrating hits.
German tanks were rolled homogenous, except on the front hull and turrets of the Mk III and Mk IV, that were face hardened of 30 to 50mm thickness, till it was discontinued in 1944, Before that, FH was 600BN Face and 320 behind