By the markings on it and the serial number. Go to proofhouse.com or call Colt Mfg. Co.
Good pistol
If your Colt is the 1911 military pistol, it was made in 1915.
1911, and remodled in 1927
If you mean the standard Caliber of a 1911 model colt pistol,then this was chambered in the caliber .45ACP.
'ACP' means Automatic Colt Pistol. A 1911, for example, would chamber a .45 ACP cartridge.
1981
No
Here is a good page on how to field strip and clean the colt 1911 pistol. http://www.bobtuley.com/45/magazine1.htm
Colt Firearms ((named for its founder, Samuel Colt) was one of the firms that made the US Military Pistol, Cal .45 ACP, Model 1911. It was adopted by the US Government in the year 1911.
1911
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