Hi John:
The best source I have for this is Hogg's book, "British and American Artillery of WWII". I find my copy tonight and read up on it for you.
Best I remember there was no difference between the ammo used by tankers and anti-tankers (Aunty Tankers was a lovely old gal but she drank alot!
)
There was likely a small difference in propellant charge for different weight projectiles to keep the EFCs and recoil wear about the same. Anyway, I speculate... better to read and get it right!
Cheers! Mike
By the way, are there captions to go with those photos? I'm building up a display to go with our gun and would like to add those photos.
