The U.S. procured around 2.7 million M1911 and M1911A1 pistols in military contracts during its service life. The M1911 was replaced by the 9mm Beretta M9 pistol as the standard U.S. sidearm in October 1986, but due to its popularity among users, it has not been completely phased out. Modernized derivative variants of the M1911 are still in use by some units of the U.S. Army Special Forces, the U.S. Navy and U.S. Marine Corps.
Designed by John Browning, the M1911 is the best-known of his designs to use the short recoil principle in its basic design. The pistol was widely copied, and this operating system rose to become the preeminent type of the 20th century and of nearly all modern centerfire pistols. It is popular with civilian shooters in competitive events such as USPSA, IDPA, International Practical Shooting Confederation, and Bullseye shooting. Compact variants are popular civilian concealed carry weapons in the U.S. because of the design's relatively slim width and stopping power of the .45 ACP cartridge. 
These are the complete set of revised 1928 military Drawings.
 from (https://en.wikipedia.org/wiki/M1911_pistol)