However, the U.S. Army did not officially replace the M1911A1 with the Beretta M9 until October 1986; production and procurement delays kept the 1911A1 in service with some units past 1989.

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.

[21] 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.

[22] 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.

[23] The problems prompted the Chief of Ordnance, General William Crozier, to authorize further testing for a new service pistol.

[23] 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).

The Director of Civilian Marksmanship began manufacture of M1911 pistols for members of the National Rifle Association of America in August 1912.

[26] 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-UMC and North American Arms Co. of Quebec.

[29] 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).

[23] Before World War II, 500 M1911s were produced under license by the Norwegian arms factory Kongsberg Vaapenfabrikk, as Automatisk Pistol Model 1912.

[30] Between 1927 and 1966, 102,000 M1911 pistols were produced as Sistema Colt Modelo 1927 in Argentina, first by the Dirección General de Fabricaciones Militares.

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 (500).

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.

At the end of hostilities the government cancelled all contracts for further production and made use of existing stocks of weapons to equip personnel.

[35] It was used during Desert Storm in specialized U.S. Army units and 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.

The Army contested this result and subsequently ran its own competition in 1981, the XM9 trials, eventually leading to the official adoption of the Beretta 92F on January 14, 1985.

[citation needed]) 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.

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.

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.

[47] Despite being challenged by newer and lighter weight pistol designs in .45 caliber, such as the Glock 21, the SIG Sauer P220, the 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, IDPA, IPSC, and Bullseye.

[13] In 1986, the USMC Precision Weapon Section (PWS) at Marine Corps Base Quantico began customizing M1911A1s for reconnaissance units.

[54] Kimber shortly began producing a limited number of what would be later termed the Interim Close Quarters Battle pistol (ICQB).

These modifications can range from changing the external finish, checkering the frame, to hand fitting custom hammers, triggers, and sears.

[61] A common modification of John Browning's design is to use a full-length guide rod that runs the full length of the recoil spring.

[citation needed] Many military and law enforcement organizations in the U.S. and other countries continue to use (often modified) M1911A1 pistols including Los Angeles Police Department SWAT and S.I.S., the FBI Hostage Rescue Team, FBI regional SWAT teams, and 1st Special Forces Operational Detachment—Delta (Delta Force).

There are a growing number of manufacturers of M1911-style pistols and the model continues to be quite popular for its reliability, simplicity, and patriotic appeal.

Price ranges from a low end of around $400 for basic models imported from Turkey (TİSAŞ and GİRSAN) and the Philippines (Armscor, Metro Arms, and SAM Inc.) to more than $4,000 for the best competition or tactical versions (Wilson Combat, Ed Brown, Les Baer, Nighthawk Custom, and Staccato).

[13] The goal was to produce a minimum of seven variants with various sights, internal and external extractors, flat and arched mainspring housings, integral and add-on magazine wells, a variety of finishes and other options, with the idea of providing the end-user a selection from which to select the features that best fit their missions.

[13] The AMU performed a well-received demonstration of the first group of pistols to the Marine Corps at Quantico and various Special Operations units at Ft. Bragg and other locations.