ORIGINAL: Mad Russian
Something to consider with the earlier war tanks. A grenade is 40mm. When at tank with a 50mm gun fires an HE shell that's just a bit better than a single hand grenade.
The quantity of explosives in a given shell is not solely determined by its diameter is it? The length of the shell is an equally important factor in its total capacity, so an elongated HE round with a similar diameter to a hand grenade will generally be far more powerful, surely...
WitE2 tester, WitW, WitP, CMMO, CM2, GTOS, GTMF, WP & WPP, TOAW4, BA2