Interwar 3 pounder tank gun?

I would like to learn more about the 3 pounder tank gun used in, amongst others, the Vickers Medium tanks in the 30's. Specs, performance etc.

 

There were two different versions of the gun, with different barrel lengths (L/32 and L/40). Both used the same 47x351R ammo, which was slightly shorter than the 47x376R round used in the naval Hotchkiss guns in British service. APHE projectile weight was 3.25 lbs and muzzle velocity (L/40) was 1,840 fps, giving penetration of 25mm/1,000 yards/30 degrees. The formal designation was "OQF (Ordnance Quick-Firing) 3-pr 2 cwt Gun Mk II".

Tony Williams: Military gun and ammunition website and discussion forum

 

Thanks!

What sort of ammo did it fire besides the APHE? Did it have a decent HE round?

 

I'm not sure. It certainly would have been possible, as the 47mm 3-pr was a common calibre, but I don't know that the tanks carried any.

Tony Williams: Military gun and ammunition website and discussion forum

 

I checked my book "Tanks of the World 1915-1945" and found C.S.
variants of both marks of the Vickers Medium Tank. The 3-pdr was replaced by a 15-pdr mortar in the Mk I C.S. and a 3.7-in howitzer in the Mk II C.S., which perhaps suggests that the 3-pdr was not considered sufficient enough for close support?