[[File:JOHN M. BROWNING.jpg|thumb|left|upright|M1911 designer [[John Browning]]]]
[[File:JOHN M. BROWNING.jpg|thumb|left|upright|M1911 designer [[John Browning]]]]
During the end of 1899 and into 1900, a test of self-loading pistols, including entries from [[Mauser]] ([[Mauser C96|C96 "Broomhandle"]]), Mannlicher ([[Mannlicher M1894]]), and Colt ([[Colt M1900]]), was conducted.<ref name="Taylor"/>
During the end of 1899 and into 1900, a test of self-loading pistols, including entries from [[Mauser]] ([[Mauser C96|C96 "Broomhandle"]]), Mannlicher ([[Mannlicher M1894]]), and Colt ([[Colt M1900]]), was conducted.
This led to a purchase of 1,000 [[Deutsche Waffen und Munitionsfabriken|DWM]] [[Luger pistol]]s, chambered in [[7.65mm Luger]]. During field trials, these ran into some problems, especially with [[stopping power]]. Other governments had made similar complaints. Consequently, DWM produced an enlarged version of the round, the [[9×19mm Parabellum]] with fifty weapons chambered for it tested by the [[United States Army|U.S. Army]] in 1903.{{sfn|Hogg|Walter|2004|p=98}}
This led to a purchase of 1,000 [[Deutsche Waffen und Munitionsfabriken|DWM]] [[Luger pistol]]s, chambered in [[7.65mm Luger]]. During field trials, these ran into some problems, especially with [[stopping power]]. Other governments had made similar complaints. Consequently, DWM produced an enlarged version of the round, the [[9×19mm Parabellum]] with fifty weapons chambered for it tested by the [[United States Army|U.S. Army]] in 1903.{{sfn|Hogg|Walter|2004|p=98}}
American units fighting [[Tausūg people|Tausūg]] guerrillas in the [[Moro Rebellion]] in Sulu during the [[Philippine–American War]] using the then-standard [[Colt M1892]] revolver, [[.38 Long Colt]], found it to be unsuitable for the rigors of [[jungle warfare]], particularly in terms of [[stopping power]], as the Moros had high battle morale and often used drugs to inhibit the sensation of pain. The U.S. Army briefly reverted to using the [[Colt Single Action Army|M1873 single-action revolver]] in [[.45 Colt]] caliber, which had been standard during the late 19th century; the heavier bullet was found to be more effective against charging tribesmen. The problems prompted the [[Chief of Ordnance]], General [[William Crozier (artillerist)|William Crozier]], to authorize further testing for a new service pistol.<ref name="Poyer" />
American units fighting [[Tausūg people|Tausūg]] guerrillas in the [[Moro Rebellion]] in Sulu during the [[Philippine–American War]] using the then-standard [[Colt M1892]] revolver, [[.38 Long Colt]], found it to be unsuitable for the rigors of [[jungle warfare]], particularly in terms of [[stopping power]], as the Moros had high battle morale and often used drugs to inhibit the sensation of pain. The U.S. Army briefly reverted to using the [[Colt Single Action Army|M1873 single-action revolver]] in [[.45 Colt]] caliber, which had been standard during the late 19th century; the heavier bullet was found to be more effective against charging tribesmen. The problems prompted the [[Chief of Ordnance]], General [[William Crozier (artillerist)|William Crozier]], to authorize further testing for a new service pistol.
Following the 1904 [[Thompson-LaGarde Tests|Thompson-LaGarde]] pistol round effectiveness tests, Colonel [[John T. Thompson]] stated that the new pistol "should not be of less than .45 caliber" and would preferably be semi-automatic in operation.<ref name="Poyer" /> This led to the 1906 trials of pistols from six firearms manufacturing companies (namely, [[Colt's Manufacturing Company|Colt]], [[Theodor Bergmann|Bergmann]], [[Deutsche Waffen und Munitionsfabriken]] (DWM), [[Savage Arms]], Knoble, [[Webley & Scott|Webley]], and White-Merrill).<ref name="Poyer" />
Following the 1904 [[Thompson-LaGarde Tests|Thompson-LaGarde]] pistol round effectiveness tests, Colonel [[John T. Thompson]] stated that the new pistol "should not be of less than .45 caliber" and would preferably be semi-automatic in operation. This led to the 1906 trials of pistols from six firearms manufacturing companies (namely, [[Colt's Manufacturing Company|Colt]], [[Theodor Bergmann|Bergmann]], [[Deutsche Waffen und Munitionsfabriken]] (DWM), [[Savage Arms]], Knoble, [[Webley & Scott|Webley]], and White-Merrill).
Of the six designs submitted, three were eliminated early on, leaving only the [[Savage Model 1907|Savage]], Colt, and [[Luger P08 pistol|DWM]] designs chambered in the new [[.45 ACP]] (Automatic Colt Pistol) cartridge.<ref name="Poyer"/> These three still had issues that needed correction, but only Colt and Savage resubmitted their designs. There is some debate over the reasons for DWM's withdrawal—some say they felt there was bias and that the DWM design was being used primarily as a "[[whipping boy]]" for the Savage and Colt pistols,<ref name="dmwwithdrawal">Hallock, Kenneth R. (1980), ''Hallock's .45 Auto Handbook''.</ref> though this does not fit well with the earlier 1900 purchase of the DWM design over the Colt and Steyr entries. In any case, a series of field tests from 1907 to 1911 were held to decide between the Savage and Colt designs.<ref name="Poyer"/> Both designs were improved between each round of testing, leading up to the final test before adoption.<ref name="Poyer"/>
Of the six designs submitted, three were eliminated early on, leaving only the [[Savage Model 1907|Savage]], Colt, and [[Luger P08 pistol|DWM]] designs chambered in the new [[.45 ACP]] (Automatic Colt Pistol) cartridge. These three still had issues that needed correction, but only Colt and Savage resubmitted their designs. There is some debate over the reasons for DWM's withdrawal—some say they felt there was bias and that the DWM design was being used primarily as a "[[whipping boy]]" for the Savage and Colt pistols,Hallock, Kenneth R. (1980), ''Hallock's .45 Auto Handbook''. though this does not fit well with the earlier 1900 purchase of the DWM design over the Colt and Steyr entries. In any case, a series of field tests from 1907 to 1911 were held to decide between the Savage and Colt designs. Both designs were improved between each round of testing, leading up to the final test before adoption.
Among the areas of success for the Colt was a test at the end of 1910 attended by its designer, John Browning. Six thousand rounds were fired from a single pistol over the course of two days. When the gun began to grow hot, it was simply immersed in water to cool it. The Colt gun passed with no reported malfunctions, while the Savage designs had 37.<ref name="Poyer"/>
Among the areas of success for the Colt was a test at the end of 1910 attended by its designer, John Browning. Six thousand rounds were fired from a single pistol over the course of two days. When the gun began to grow hot, it was simply immersed in water to cool it. The Colt gun passed with no reported malfunctions, while the Savage designs had 37.
===Service history===
===Service history===
Following its success in trials, the Colt pistol was formally adopted by the Army on March 29, 1911, when it was designated "Model of 1911", later changed in 1917 to "Model 1911", and then "M1911" in the mid-1920s. The [[Director of Civilian Marksmanship]] began manufacture of M1911 pistols for members of the [[National Rifle Association of America]] in August 1912. Approximately 100 pistols stamped "N.R.A." below the serial number were manufactured at Springfield Armory and by Colt. The M1911 was formally adopted by the [[United States Navy|U.S. Navy]] and [[United States Marine Corps|Marine Corps]] in 1913. The .45 ACP "Model of 1911 U.S. Army" was used by both U.S. Army Cavalry troops and infantry soldiers during the United States' [[Pancho Villa Expedition|Punitive Expedition]] into Mexico against Pancho Villa in 1916.<ref></ref>
Following its success in trials, the Colt pistol was formally adopted by the Army on March 29, 1911, when it was designated "Model of 1911", later changed in 1917 to "Model 1911", and then "M1911" in the mid-1920s. The [[Director of Civilian Marksmanship]] began manufacture of M1911 pistols for members of the [[National Rifle Association of America]] in August 1912. Approximately 100 pistols stamped "N.R.A." below the serial number were manufactured at Springfield Armory and by Colt. The M1911 was formally adopted by the [[United States Navy|U.S. Navy]] and [[United States Marine Corps|Marine Corps]] in 1913. The .45 ACP "Model of 1911 U.S. Army" was used by both U.S. Army Cavalry troops and infantry soldiers during the United States' [[Pancho Villa Expedition|Punitive Expedition]] into Mexico against Pancho Villa in 1916.
====World War I====
By the beginning of 1917, a total of 68,533 M1911 pistols had been delivered to U.S. armed forces by Colt's Patent Firearms Manufacturing Company and the U.S. government's [[Springfield Armory]]. However, the need to greatly expand U.S. military forces and the resultant surge in demand for the firearm in [[World War I]] saw the expansion of manufacture to other contractors besides Colt and Springfield Armory, including Remington-[[Union Metallic Cartridge Company|UMC]] and [[North American Arms]] Co. of Quebec.{{sfn|Hogg|Walter|2004|p=83}} Several other manufacturers were awarded contracts to produce the M1911, including the [[NCR Corporation|National Cash Register Company]], the [[Savage Arms]] Company, the Caron Brothers Manufacturing of Montreal, the [[Burroughs Corporation|Burroughs Adding Machine Co.]], [[Winchester Repeating Arms Company]], and the [[Lanston Monotype Company]], but the signing of the Armistice resulted in the cancellation of the contracts before any pistols had been produced.{{sfn|Thompson|2011|p=26}}
====Interwar changes====
Battlefield experience in World War I led to some more small external changes, completed in 1924. The new version received a modified type classification, M1911A1, in 1926 with a stipulation that M1911A1s should have serial numbers higher than 700,000 with lower serial numbers designated M1911.<ref>Canfield, Bruce N. ''[[American Rifleman]]'' June 2005, p. 26</ref> The M1911A1 changes to the original design consisted of a shorter trigger, cutouts in the frame behind the trigger, an arched mainspring housing, a longer grip safety spur (to prevent [[hammer bite]]), a wider front sight, a shortened hammer spur, and simplified grip checkering (eliminating the "Double Diamond" reliefs).<ref name="Poyer" /> These changes were subtle and largely intended to make the pistol easier to shoot for those with smaller hands. No significant internal changes were made, and parts remained interchangeable between the M1911 and the M1911A1.<ref name="Poyer" />
Working for the U.S. Ordnance Office, [[David Marshall Williams]] developed a [[Sub-caliber training|.22 training]] version of the M1911 using a [[Floating chamber (firearms)|floating chamber]] to give the .22 long rifle rimfire recoil similar to the .45 version.<ref name="Poyer" /> As the [[Colt Service Ace]], this was available both as a pistol and as a conversion kit for .45 M1911 pistols.<ref name="Poyer" />
Before World War II, 500 M1911s were produced under license by the Norwegian arms factory ''[[Kongsberg Gruppen|Kongsberg Vaapenfabrikk]]'', as ''Automatisk Pistol Model 1912''. Then, production moved to a modified version designated ''Pistol Model 1914'' and unofficially known as "[[Kongsberg Colt]]". The Pistol M/1914 is noted for its unusual extended slide stop which was specified by Norwegian ordnance authorities. Twenty-two thousand were produced between 1914 and 1940 but production continued after the German occupation of Norway in 1940 and 10,000 were produced for the German armed forces as ''Pistole 657 (n)''. {{sfn|Thompson|2011|pp=64-65}}
Between 1927 and 1966, 102,000 M1911 pistols were produced as ''Sistema Colt Modelo 1927'' in [[Argentina]], first by the [[Fabricaciones Militares|Dirección General de Fabricaciones Militares]]. A similar gun, the [[Ballester–Molina]], was also designed and produced.{{sfn|Thompson|2011|p=65}}
The M1911 and M1911A1 pistols were also ordered from Colt or produced domestically in modified form by several other nations, including Brazil (M1937 contract pistol), Mexico (M1911 Mexican contract pistol and the [[Obregón pistol]]), and Spain (private manufacturers [[Star Bonifacio Echeverria|Star]] and [[Llama firearms|Llama]]).{{Citation needed|date=July 2023}}
====World War II====
[[World War II]] and the years leading up to it created a great demand. During the war, about 1.9 million units were procured by the U.S. Government for all forces, production being undertaken by several manufacturers, including [[Remington Rand]] (900,000 produced), Colt (400,000), [[Ithaca Gun Company]] (400,000), [[Union Switch & Signal]] (50,000), and [[Singer Corporation|Singer]] (500). New M1911A1 pistols were given a [[parkerize]]d metal finish instead of bluing, and the wood grip panels were replaced with panels made of brown plastic. The M1911A1 was a favored small arm of both U.S. and allied military personnel during the war, in particular, the pistol was prized by some British commando units and Britain's highly covert [[Special Operations Executive]], as well as South African Commonwealth forces.{{sfn|Thompson|2011|p=48}}
The M1911A1 pistol was produced in very large quantities during the war. At the end of hostilities the government cancelled all contracts for further production and made use of existing stocks of weapons to equip personnel. Many of these weapons had seen service use, and had to be rebuilt and refinished prior to being issued. From the mid-1920s to the mid-1950s thousands of 1911s and 1911A1s were refurbished at U.S. arsenals and service depots. These rebuilds consisted of anything from minor inspections to major overhauls. Pistols that were refurbished at government arsenals will usually be marked on the frame/receiver with the arsenal's initials, such as RIA for Rock Island Armory or SA for Springfield Armory.{{citation needed|date=March 2021}}
Among collectors today, the Singer-produced pistols in particular are highly prized, commanding high prices even in poor condition.
====General Officer's Model====
{{unreferenced section|date=March 2021}}
From 1943 to 1945 a fine-grade russet-leather M1916 pistol belt set was issued to some generals in the U.S. Army. It was composed of a leather belt, leather enclosed flap-holster with braided leather tie-down leg strap, leather two-pocket magazine pouch, and a rope lanyard. The metal buckle and fittings were in gilded brass. The buckle had the seal of the U.S. on the center (or "male") piece and a laurel wreath on the circular (or "female") piece. The pistol was a standard-issue M1911A1 that came with a cleaning kit and three magazines.
From 1972 to 1981 a modified M1911A1 called the [[M15 pistol|RIA M15 General Officer's Model]] was issued to general officers in the U.S. Army and U.S. Air Force. From 1982 to 1986 the regular M1911A1 was issued. Both came with a black leather belt, open holster with retaining strap, and a two-pocket magazine pouch. The metal buckle and fittings were similar to the M1916 General Officer's Model except it came in gold metal for the Army and in silver metal for the Air Force.
====Post–World War II usage====
After World War II, the M1911 continued to be a mainstay of the U.S. Armed Forces in the [[Korean War]] and the [[Vietnam War]], where it was used extensively by [[tunnel rats]]. It was used during [[Desert Storm]] in specialized U.S. Army units and [[Seabee|U.S. Navy Mobile Construction Battalions (Seabees)]], and has seen service in both [[Operation Iraqi Freedom]] and [[Operation Enduring Freedom]], with U.S. Army Special Forces Groups and Marine Corps Force Reconnaissance Companies.<ref name=Campbell>
However, by the late 1970s, the M1911A1 was acknowledged to be showing its age. Under political pressure from Congress to standardize on a single modern pistol design, the [[United States Air Force|U.S. Air Force]] ran a [[Joint Service Small Arms Program]] to select a new semi-automatic pistol using the [[NATO]]-standard 9mm Parabellum pistol cartridge. After trials, the [[Beretta 92|Beretta 92S-1]] was chosen. The Army contested this result and subsequently ran its own competition in 1981, the [[Beretta M9|XM9]] trials, eventually leading to the official adoption of the [[Beretta 92#Evolution|Beretta 92F]] on January 14, 1985.<ref name="New York Times Biddle"> By the late 1980s production was ramping up despite a controversial XM9 retrial and a separate XM10 reconfirmation that was boycotted by some entrants of the original trials, cracks in the frames of some pre-M9 Beretta-produced pistols, and despite a problem with slide separation using higher-than-specified-pressure rounds that resulted in injuries to some U.S. Navy special operations operatives. This last issue resulted in an updated model that includes additional protection for the user, the 92FS, and updates to the ammunition used.<ref name=gd2011> During the [[Gulf War]] of 1990–1991, M1911A1s were deployed with reserve component U.S. Army units sent to participate in Operations Desert Shield and Desert Storm.
By the early 1990s, most M1911A1s had been replaced by the [[Beretta M9]], though a limited number remain in use by special units. The [[United States Marine Corps|U.S. Marine Corps]] (USMC) in particular were noted for continuing the use of M1911 pistols for selected personnel in MEU(SOC) and reconnaissance units (though the USMC also purchased over 50,000 M9 pistols.{{citation needed|date=August 2016}}) For its part, the [[United States Special Operations Command]] (USSOCOM) issued a requirement for a [[.45 ACP]] pistol in the Offensive Handgun Weapon System (OHWS) trials. This resulted in the Heckler & Koch OHWS becoming the [[Heckler & Koch Mark 23 Mod 0|MK23 Mod 0]] Offensive Handgun Weapon System (itself being heavily based on the 1911's basic field strip), beating the [[Colt OHWS]], a much-modified M1911. Dissatisfaction with the stopping power of the 9 mm Parabellum cartridge used in the Beretta M9 has actually promoted re-adoption of pistols based on the .45 ACP cartridge such as the M1911 design, along with other pistols, among USSOCOM units in recent years, though the M9 has been predominant both within SOCOM and in the U.S. military in general.<ref name=Campbell />
==Design==
[[File:Colt M1911 cross-section diagram.jpg|thumb|right|Cross-section diagram, with labeled parts, of original Model 1911 pistol, from official Army description as published in 1917.]]
[[File:COLT M1911A1 fieldstrip noBG 2.jpg|thumb|right|Springfield Mil Spec field stripped]]
Browning's basic M1911 design has seen very little change throughout its production life.<ref name="Manual" />{{page needed|date=March 2021}} The basic principle of the pistol is recoil operation.<ref name="Manual" />{{page needed|date=March 2021}} As the expanding combustion gases force the bullet down the barrel, they give reverse momentum to the slide and barrel which are locked together during this portion of the firing cycle. After the bullet has left the barrel, the slide and barrel continue rearward a short distance.<ref name="Manual" />{{page needed|date=March 2021}}
At this point, a link pivots the rear of the barrel down, out of locking recesses in the slide, and the barrel is stopped by making contact with the lower barrel lugs against the frame. As the slide continues rearward, a claw extractor pulls the spent casing from the firing chamber and an ejector strikes the rear of the case, pivoting the casing out and away from the pistol through the ejection port. The slide stops its rearward motion then, and is propelled forward again by the recoil spring to strip a fresh cartridge from the magazine and feed it into the firing chamber. At the forward end of its travel, the slide locks into the barrel and is ready to fire again.
However, if the fired round was the last in the magazine, the slide will lock in the rearward position, which notifies the shooter to reload by ejecting the empty magazine and inserting a loaded magazine, and facilitates (by being rearwards) reloading the chamber, which is accomplished by either pulling the slide back slightly and releasing, or by pushing down on the slide stop, which releases the slide to move forward under spring pressure, strip a fresh cartridge from the magazine, and feed it into the firing chamber.<ref name="Manual" />{{page needed|date=March 2021}}
Other than grip screws there are no fasteners of any type in the 1911 design. The main components of the gun are held in place by the force of the main spring. The pistol can be "field stripped" by partially retracting the slide, removing the slide stop, and removing the barrel bushing. Full disassembly (and subsequent reassembly) of the pistol to its component parts can be accomplished using several manually removed components as tools to complete the disassembly.{{citation needed|date=March 2021}}
The military mandated a [[grip safety]] and a [[manual safety]].<ref name="Manual" />{{page needed|date=March 2021}} A grip safety, [[sear (firearm)|sear]] disconnect, slide stop, half cock position, and manual safety (located on the left rear of the frame) are on all standard M1911A1s.<ref name="Manual" /> Several companies have developed a [[safety (firearms)|firing pin block safety]]. Colt's 80 series uses a trigger operated one and several other manufacturers, including Kimber and Smith & Wesson, use a Swartz firing-pin safety, which is operated by the grip safety.
The same basic design has been offered commercially and has been used by other militaries. In addition to the .45 ACP (Automatic Colt Pistol), models chambered for [[.38 Super]], [[9×19mm Parabellum]], [[7.65mm Parabellum]], [[9mm Steyr]], [[.400 Corbon]], and other cartridges were offered. The M1911 was developed from earlier [[Colt's Manufacturing Company|Colt]] semi-automatic designs, firing rounds such as [[.38 ACP]]. The design beat out many other contenders during the government's selection period, during the late 1890s and early 1900s, up to the pistol's adoption. The M1911 officially replaced a range of revolvers and pistols across branches of the U.S. armed forces, though a number of other designs have seen use in certain niches.
Despite being challenged by newer and lighter weight pistol designs in .45 caliber, such as the [[Glock#.45 ACP|Glock 21]], the [[SIG Sauer P220]], the [[HS2000|Springfield XD]] and the [[Heckler & Koch USP]], the M1911 shows no signs of decreasing popularity and continues to be widely present in various competitive matches such as those of USPSA, [[International Defensive Pistol Association|IDPA]], [[International Practical Shooting Confederation|IPSC]], and [[Bullseye (shooting competition)|Bullseye]].
The Colt M1911 (also known as 1911, Colt 1911 or Colt Government in the case of Colt-produced models) is a single-action, recoil-operated, semi-automatic pistol chambered for the .45 ACPcartridge.The pistol's formal U.S. military designation as of 1940 was Automatic Pistol, Caliber .45, M1911 for the original model adopted in March 1911, and Automatic Pistol, Caliber .45, M1911A1 for the improved M1911A1 model which entered service in 1926. The designation changed to Pistol, Caliber .45, Automatic, M1911A1 in the Vietnam War era.
The U.S. military procured around 2.7 million M1911 and M1911A1 pistols during its service life. The pistol served as the standard-issue sidearm for the United States Armed Forces from 1911 to 1985. It was widely used in World War I, World War II, the Korean War, and the Vietnam War. The M1911A1 was replaced by the adoption of the 9mmBeretta M9 pistol as the standard U.S. military sidearm in 1985. However, the U.S. Army did not officially replace the M1911A1 with the Beretta M9 until October 1986, but shortages in production and procurement kept the 1911A1 in service with some units past 1989. The 1911A1 has never been completely phased out. Modernized derivative variants of the M1911 are still in use by some units of the U.S. Army Special Forces, U.S. Marine Corps and the U.S. Navy.
History
Early history and adaptations
The M1911 pistol originated in the late 1890s as the result of a search for a suitable self-loading (or semi-automatic) pistol to replace the variety of revolvers in service at the time.
The United States was adopting new firearms at a phenomenal rate; several new pistols and two all-new service rifles (M1892/96/98 Krag and M1895 Navy Lee), as well as a series of revolvers by Colt and Smith & Wesson for the Army and Navy, were adopted just in that decade.[citation needed]
The next decade would see a similar pace, including the adoption of several more revolvers and an intensive search for a self-loading pistol that would culminate in the official adoption of the M1911 after the turn of the decade.[citation needed]
Hiram S. Maxim had designed a self-loading rifle in the 1880s, but was preoccupied with machine guns. Nevertheless, the application of his principle of using cartridge energy to reload led to several self-loading pistols in 1896. The designs caught the attention of various militaries, each of which began programs to find a suitable one for their forces. In the U.S., such a program would lead to a formal test at the turn of the 20th century.[1]
This led to a purchase of 1,000 DWMLuger pistols, chambered in 7.65mm Luger. During field trials, these ran into some problems, especially with stopping power. Other governments had made similar complaints. Consequently, DWM produced an enlarged version of the round, the 9×19mm Parabellum with fifty weapons chambered for it tested by the U.S. Army in 1903.[2]
American units fighting Tausūg guerrillas in the Moro Rebellion in Sulu during the Philippine–American War using the then-standard Colt M1892 revolver, .38 Long Colt, found it to be unsuitable for the rigors of jungle warfare, particularly in terms of stopping power, as the Moros had high battle morale and often used drugs to inhibit the sensation of pain. The U.S. Army briefly reverted to using the M1873 single-action revolver in .45 Colt caliber, which had been standard during the late 19th century; the heavier bullet was found to be more effective against charging tribesmen. The problems prompted the Chief of Ordnance, General William Crozier, to authorize further testing for a new service pistol.
Following the 1904 Thompson-LaGarde pistol round effectiveness tests, Colonel John T. Thompson stated that the new pistol "should not be of less than .45 caliber" and would preferably be semi-automatic in operation. This led to the 1906 trials of pistols from six firearms manufacturing companies (namely, Colt, Bergmann, Deutsche Waffen und Munitionsfabriken (DWM), Savage Arms, Knoble, Webley, and White-Merrill).
Of the six designs submitted, three were eliminated early on, leaving only the Savage, Colt, and DWM designs chambered in the new .45 ACP (Automatic Colt Pistol) cartridge. These three still had issues that needed correction, but only Colt and Savage resubmitted their designs. There is some debate over the reasons for DWM's withdrawal—some say they felt there was bias and that the DWM design was being used primarily as a "whipping boy" for the Savage and Colt pistols,Hallock, Kenneth R. (1980), Hallock's .45 Auto Handbook. though this does not fit well with the earlier 1900 purchase of the DWM design over the Colt and Steyr entries. In any case, a series of field tests from 1907 to 1911 were held to decide between the Savage and Colt designs. Both designs were improved between each round of testing, leading up to the final test before adoption.
Among the areas of success for the Colt was a test at the end of 1910 attended by its designer, John Browning. Six thousand rounds were fired from a single pistol over the course of two days. When the gun began to grow hot, it was simply immersed in water to cool it. The Colt gun passed with no reported malfunctions, while the Savage designs had 37.
Service history
Following its success in trials, the Colt pistol was formally adopted by the Army on March 29, 1911, when it was designated "Model of 1911", later changed in 1917 to "Model 1911", and then "M1911" in the mid-1920s. The Director of Civilian Marksmanship began manufacture of M1911 pistols for members of the National Rifle Association of America in August 1912. Approximately 100 pistols stamped "N.R.A." below the serial number were manufactured at Springfield Armory and by Colt. The M1911 was formally adopted by the U.S. Navy and Marine Corps in 1913. The .45 ACP "Model of 1911 U.S. Army" was used by both U.S. Army Cavalry troops and infantry soldiers during the United States' Punitive Expedition into Mexico against Pancho Villa in 1916.
