I have what may be an ignorant question (If so forgive me). Why did Glock choose 45 calibre for its new cartridge? I understand that the 45GAP is sort of like a short 45acp but they do use different brass, don't they? Not just trimmed acp brass. They do use the same bullets though, so I guess that is a reason. It seems from another thread, that you can use 45acp dies to reload 45 GAP, so I guess that another reason. Why not go to a larger calibre, to avoid the obvious comparisons between the two rounds? I saw an ad in a gun rag for some kind of cartridge called the 50GI in a 1911 style pistol. The web site claims a 300gr. bullet at 700-900fps, depending on the load. The case is 45acp length, but it could have be shortened just like the 45. Just think of the bragging rights of owning a 50 calibre Glock. The full size pistol would still hold 10 rounds (probably 11 or 12). It certainly would bring a whole new dimension to the 9 vs 45 argument. I bet they would have sold like hotcakes.