"British tank main guns" Topic

In 1939 Britain had the 2 pdr, which for all the complaints that have circled around it had outstanding if not the best anti armor performance of any tank gun in service at the time. The British had an interesting progression in tank main battery weapons. They went from a fairly high velocity 6 pdr to a cut down version of the same gun (the barrel length of the original tended to put the gun muzzle in the mud far too often on the Western Front). They they went to a fairly hot 3 pdr which remained the primary tank weapon for almost twenty years. This was replaced by the 2 pdr. The 2 pdr had little use except firing against tanks so some of the machines with 3 inch and 3.7 inch howitzers that fired smoke and some HE.

Now my question is why didn't they go back to the long barreled 6 pdr instead of developing the 2 pdr and the various CS howitzers when they decided to get rid of the 3 pdr? It already had an effective family of ammunition. It could have been updated, lightened and given a more powerful charge but the weapon was sound and certainly better than almost any weapon that was seen on the battlefield up until the Soviet 76mm guns went into service on the T-34 and the KV-1.

A Matlida II designed with this weapon from the start would have been a far better machine.

Does anyone have the penetration figures for the long barreled Hotchkiss 6 pdr, the British tank mounted 3 pdr weapons? I have good data for the 2 pdr of course.

Terry

Between the wars, British tank design was left in the hands of private industry, Vickers being preeminent. The trend was for cheaper,lighter vehicles with more mobility, that meant designs such as the Vickers 6 ton series,.
These were much faster than the WW1 designs, but with weak powerplants that meant thin armour and small turrets. The British fixation with small turret rings was to handicap their designs until '44/45.
International tank design trends were similar, the French 37 mm low velocity gun was the norm for gun armed tanks, although the Soviets developed the 45 mm from the German Pak 37in the late Thirties and installed it in their T26 -itself a development of the Vickers 6 ton. The 2 pdr was potent in its role as an anti tank weapon but British doctrine was for armour to exploit the breakthrough not to engage and destroy enemy tanks. Hence the development of howitzer armed vehicles for infantry support, the idea of a dual purpose gun seems to have escaped the designers entirely- not lost on the retired WW1 designers and their TOG1 design. The classic failing of the 2 pdr was the lack of an H E round, designed but never produced -another failure of British govt/industry.

Edit -an excellent read 'Rude Mechanicals -the development of British tank design', a tale of bean counters,nay-sayers and prophets!

For performance of the 3pdr. take a look at tables for the Italian 47mm. gun. Virtually a copy.

Another good book is The Great Tank Scandal by David Fletcher or Death by Design.