The M1911 is a 45. APC semi-autimatic pistol. The M1911 was Created in 1909 by Colt as a semi-auto pistol, then named M1909, for the US Army. The pistol didn't enter service in the US Army until 1911 thus gave it the name Model 1911 Pistol. The M1911's magazines hold 7, 45.APC rounds. It was pulled from service and replaced in 1990 by the M9 Pistol.
It has seen limited service in the US Army in the Modern Battlefield as it is by some standards obsolete.