I suppose the two different guns already existed, and that is why these two "tanks" used different cannon.? It seems funny they had two guns of such close caliber... or does it.? I am not a military expert, and WWII is just a casual hobby for me. But i have always wondered why the 76mm gun was not used in The Sherman Tank..... would it fit.? Would it have made sense, when a "better" gun was needed, to simply improve the 75mm gun of The Sherman. Could the case have been lengthened, for more velocity, and the projectile Changed/Improved to take on the Armor Piercing job.? Thank You
Ok, a quick couple of things to note. The M10 is not a tank. It was a gun motor carriage and was used by the US Army as a Tank Destroyer. The 76mm gun was actually designated a 3" gun and was huge, having its origins in an anti-aircraft gun. The breach was large and wouldn't really fit in anything other than an open turret. The 75mm gun was something different entirely and was actually a very good gun for WW2. The later 76mm M1 gun used on the E6 Shermans was the same caliber as the 3" but was staggeringly half the weight and was significantly smaller. They both used the same projectile.
And I would note, regarding "when a better gun was needed" - if you're thinking of after D-Day - that the Americans had already created the 76mm gun and built Shermans with it at that point.
