It was the most used pistol in the United States Military from 1911-1985, when it was replaced by the 9mm caliber Beretta M9, a military version of the Beretta 92. The M1911 was replaced because military leaders liked that the Beretta pistol could hold more bullets. Another reason was because other NATO countries pressured the US to follow a rule that all NATO weapons must use the same ammunition. Even after the Beretta M9 officially replaced the M1911, many US soldiers still use the M1911 in combat. The M1911 is a common pistol design for police and special forces because it is reliable in function, easy to modify by a gunsmith, and effective. 