Colt . 45 The Colt 1911 Caliber . 45 is a pistol created by john Browning to the U . S Army , this pistol is currently used by many armies in the world , including United States , which is currently being replaced by the Berretta M9 , but his great specifications shows that this pistol will be used by many years in various armies . Description . The history of the Colt Gov ' t / M1911 Pistol began in early 1900s , when famous designer John M . Browning began to develop semi - automatic pistols for Colt company . In the 1906 - 1907 U . S . Army announced trials to replace its service revolvers with new , semi - automatic pistol . Army required the new pistol to have the caliber of . 45 inch , so Browning designed its own cartridge that fired 230 grains ( 15 . 64 gramms ) bullet , and then , designed a new pistol . In 1911 , after extensive testings , the new pistol and its cartridge , designed by Browning and manufactured by Colt , were adopted for U . S . military service as M1911 . Prior to and during World War I , more than one million of these guns were manufactured , mostly by Colt and Springfield Armoury , as well as by Remington - UMC , Burroughs , Savage and some other companies . The rights to manufacture Colt / Browning design were also sold to some foreign countries , such as Norway or Argentine . In 1926 , original design was improved , following the recommendations of the US Army Ordnanve Dept . These changes incorporate the following items ( see picture above ) : 1 . Wider front sight 2 . Longer hammer spur 3 . Shorter trigger 4 . Curved spring housing 5 . Simplified grip panels checkering 6 . Index finger reliefs behind the trigger 7 . Longer grip - safety spur The improved design was adopted by US Military as M1911A1 pistol , and served with distinction until the mid - 1980s , when it was officially replaced in service with M9 pistol ( US - made Beretta 92FS ) . The commercial Colts of this design are known as Government models . In 1929 , Colt introduced the Government pistol in its new chambering , the . 38 Super Automatic , a hotter version of the earlier . 38 Automatic cartridge . New pistol had bigger magazine capacity ( 9 rounds ) and sold well on the police market . The . 38 Super versions are still manufactured and used mostly as competition guns due to extreme accuracy . During the 1970 - 1983 , Colt manufactured Mk . IV series 70 Government model pistols , which closely resembled original M1911A1s , but with accurized barrel bushings . Since 1983 , Colt manufactured Mk . IV Series 80 Government model pistols , that featured added firing pin safety . Latest Colt product , M1991A1 , also featured Series 80 slide with firing pin safety . Colt also developed some more compact versions of its full - size commercial guns . So called " Commander " versions ( available as Combat Commanders , Lightweight Commanders with alloy frames etc . ) have shortened barrels and slides ( barrel length 108 mm , or 4 . 25 inch ) , with the standart size frame and grip , and standart magazine capacity of 7 rounds in . 45 ACP . These guns were also available in . 38 Super and 9mm Parabellum chamberings . In the year 1972 , US Army adopted the M15 General Officers Model Pistol , developed by Rock Island Arsenal , wery similar to Combat Commander , as a selfdefence weapon for high level army officers . These guns had a brass plate insert in the left grip panel , where tha name of the owner should be engraved . Even more compact version , the Colt Defender , had also the shorter grip that limits magazine capacity to 6 rounds of . 45ACP . The barrel of Defender is of 76 mm length ( 3 inch ) . Commercial Colt Officers ' pistols were also very similar to Defenders . Along with Colt , countless numbers of companie in the USA and other countries manufactured more or less exact copies of the M1911 . Some millions of guns were manufactured in the USA during the WW2 by numerous companies under US Government contracts , and probably even more were manufactured for commercial sales . Most common M1911 clones are manufactured by : Springfield armoury , Les Baer , Kimber , Wilson , STI , Para Ordnance and many , many others . Also , many M1911 - partterned pistols are still custom built for service duty , sport shooting and self - defence . Technically , the M1911 is a recoil operated , locked breech semi - auto pistol . It has single action trigger with frame mounted safety that locks the hammer and the slide . Hammer could be locked either in cocked or in lowered position , allowing the gun to be carried in " cocked and locked " state , with safety on , hammer cocked and round chambered . Additional automated safety incorporated into rear of the grip and locks the action when gun not held in the hand properly . Barrel and slide are interlocked via massive lugs on the upper part of the barrel , just ahead of the chamber . After the shot is fired , the barrel and the slide go back for the short distance , then rear part of the barrel is lovered by tilting link , and barrel unlocks the slide . The slide goes all the way back , extracting and ejecting spent case and chambering the new round on the way back . When magazine is empty , the magazine follower activates slide stop that locks the slide in the open ( rear ) position . The gun is fed from the single stack , seven round magazine . The magazine release button is located on the left side of the frame , just behind the triggerguard . Modern Gov ' t / 1911 clones may differ , more or less , from this description : i . e . , those guns may have widebody frames that can accept dual stack , high capacity magazines ; frames could be made from steel , alluminium alloys or polymer ; some could have Double Action or even Double Action Only triggers , ambidextrous satety switches and slide stops etc . The Colt Gov ' t / M1911 is probably the most popular pistol in the world . It is known for its reliability , serviceability , simplicity . Custom made M1911s capable of outstanding accuracy , and many of M1911 - patterned guns are still in service with different military and law enforcement agencies in the USA .