The M249 SAW, formally as the Light Machine Gun, 5.56 mm, M249 Squad Automatic Weapon, is the United States Armed Forces adaptation of the Belgian FN Minimi, a light machine gun designed and manufactured by FN Herstal.

The M249 SAW is manufactured in the United States by the subsidiary FN Manufacturing, LLC (FN America), a company in Columbia, South Carolina. It was adopted in 1982 by the U.S. Armed Forces to address the lack of sustained automatic fire capability at the squad level and has been widely used since. The M249 SAW combines the rate of fire of a machine gun with the accuracy and portability of an assault rifle.

The M249 SAW is a gas operated and air-cooled light machine gun. It features a quick-change barrel, enabling the operator to rapidly replace an overheated or obstructed barrel. It can be paired with a folding bipod attached to the front of the gas block, or attached to an M192 lightweight ground mount tripod. The M249 SAW features a dual-feeding mechanism, configured primarily as a belt-fed machine gun while also being compatible with STANAG magazines used in the M16 rifle and M4 carbine.

The M249 SAW has been fielded in major conflicts involving the United States military since the United States invasion of Panama in 1989.

In 2009, the United States Marine Corps selected the M27 Infantry Automatic Rifle to partially replace the M249 in USMC service.

In 2022, the U.S. Army selected the M250 light machine gun from SIG Sauer to replace the M249 SAW.

Developmental history In 1965, the M2 Browning and M60 were the primary machine guns of the U.S. Army and U.S. Marine Corps. The M2 was a large-caliber heavy machine gun, usually mounted on vehicles or in fixed emplacements. The M60 was a more mobile general-purpose machine gun intended to be carried by troops to provide heavy automatic fire.

Both firearms were very heavy and usually required a crew of at least two to operate efficiently., A-1 Rifle platoon. The Browning automatic rifle (BAR), the army's main individual machine gun since its introduction in World War I, was phased out in 1957 with the introduction of the M14 rifle (which had a fully automatic mode). "Designated riflemen" in every squad were ordered to use their rifles on the fully automatic setting, while other troops were required to use their rifle's semi-automatic mode on most occasions to increase accuracy and conserve ammunition. Because the M14 and M16 were not designed with sustained automatic fire in mind, they often overheated or jammed., 7–9 Automatic or burst fire. The 20-round and 30-round magazines of these rifles limited their sustained automatic effectiveness when compared to belt-fed machine guns.

The Army decided that an individual machine gun, lighter than the M60, but with more firepower than the M16, would be advantageous; troops would no longer have to rely on rifles for automatic fire.Bonds and Miller 2002, p. 451. Through the 1960s, the introduction of a machine gun into the infantry squad was examined in various studies. Most light machine gun experiments concentrated on the Stoner 63 modular weapon system, which could be easily modified for different purposes. The Stoner 63 LMG saw combat for a brief period in Vietnam with the Marine Corps, and later on a wider scale with the U.S. Navy SEALs.

In 1968, the Army Small Arms Program developed plans for a new 5.56 mm caliber LMG, though no funds were allocated (5.56 mm ammunition was viewed as underpowered by many in the armed forces). Studies of improved 5.56 mm ammunition with better performance characteristics began. The earliest reference to studies of other LMG calibers did not appear until 1969. In July 1970, the U.S. Army finally approved development of an LMG, but did not specify a caliber. At this time, the "Squad Automatic Weapon" (SAW) nomenclature was introduced.

Actual design for alternative LMG cartridges did not begin until July 1971. A month later, Frankford Arsenal decided on two cartridge designs for the new LMG: a 6 mm cartridge and a new 5.56 mm cartridge with a much larger case. Neither design was finalized by March 1972, when the Army published the specifications document for the planned SAW. The 6 mm cartridge design was eventually approved in May of that year.

Prior to July 1972, SAW development contracts were awarded to Maremont, Philco Ford, and the Rodman Laboratory at Rock Island Arsenal, which produced the XM233, XM234, and XM235, respectively. Designs were required to weigh less than including 200 rounds of ammunition, and have a range of at least .

Trials

Three 5.56 mm candidate light machine guns were included with the 6 mm candidates in initial trials: the Colt M16 HBAR; the FN Minimi; and the HK23A1. Initial trials ended in December 1974. In February 1976, the Minimi and XM235 were selected for further development, and other designs were eliminated. Opinions on the 6 mm cartridge were mixed due to the logistical implications of having multiple calibers in infantry service.

In June, it was requested that the SAW specifications document be revised to emphasize standard 5.56 mm ammunition. In October, the requested revisions were approved, and bids were solicited for the conversion of the Rodman XM235 to 5.56 mm. Production of the converted XM235 was awarded to Ford Aerospace, and its designation was changed to XM248. A new M16 HBAR variant, the XM106, was developed in 1978, and soon after, Heckler & Koch lobbied to include a 5.56 mm conversion of its HK21A1, instead of the standard 7.62 mm NATO ammunition it was built for, in future SAW testing. The latter model was designated the XM262. At this time, the FN Minimi received the designation XM249. Testing of the four candidates resumed in April 1979.

In May 1980, the FN XM249 was selected as the best choice for future development on the grounds of performance and cost, while the HK XM262 reportedly came a close second. In September, FN was awarded a "maturity phase" contract for further development of the XM249, and testing of the new light machine gun began in June 1981. The official adoption took place in February 1982.

Operational history

The FN Minimi entered U.S. Army service as the M249 SAW in 1984, and was later adopted by the U.S. Marine Corps in 1985. The U.S. production model has a different buttstock compared the original FN Minimi. It is manufactured in the FN factory in Columbia, South Carolina., Preface.

Although found to be reliable and accurate, multiple safety hazards were identified in the design, including sharp edges and an exposed hot barrel. Soldiers complained that the front sight required special tools to be adjusted. On August 23, 1985, then-U.S. Under Secretary of the Army James R. Ambrose suspended M249 production pending the development of a product improvement program (PIP). Congress removed funds for the M249 from the Fiscal Year 1986 defense budget, then retroactively set aside the program's funding for other purposes. Over 1,100 M249s already issued were to remain in use, but be retrofitted with the PIP kit when it became available. Over 7,000 M249s were to stay in storage at depots until corrective changes could be made. The PIP kit was eventually developed and implemented, and production of the M249 resumed.

Initial reactions to the M249 SAW were mixed: it fulfilled the light machine gun role well when fired from a prone position, but was not as effective when fired from the shoulder or hip. It was praised for its extreme durability and massive firepower, but was criticized for a number of issues: the blank firing adapter fitted poorly, the bipod was fragile, the sling attachment was awkward, and there were many slots and gaps that accumulated dirt. Some claimed that the heavy-barrelled version of the M16 rifle was a more effective light machine gun.

The M249 SAW was not used consistently before the 1991 Gulf War, though it has been used in every major U.S. conflict since. American personnel in Somalia in 1993, Bosnia in 1994, Kosovo in 1999, Afghanistan in 2001 and Iraq since 2003 have been issued M249s. Surplus M249s were donated to Bolivia, Colombia and Tunisia.

Tactically, M249 SAWs are either carried with a maneuvering unit and fired while handheld, or positioned to remain stationary and provide covering fire for other units. The base load of ammunition was originally 600 rounds, carried in three 200-round boxes. These boxes were carried in soft pouches labeled Case, Small Arms, Ammunition, 200-Round Magazine. The modern load of ammunition carried for the M249 is 1,000 rounds in five 200-round belts, although up to 500 extra rounds may be loaded into 100-round soft pouches.

Persian Gulf War A supply of 929 M249 SAWs was issued to personnel from the U.S. Army and Marine Corps during the Persian Gulf War. Although exposure to combat was scarce, M249 gunners who were involved in fighting mainly used their machine guns to provide cover fire for friendly maneuvering troops from fixed positions, rather than maneuvering with them. There were many complaints about the M249 clogging up with sand after prolonged use in the desert environment.

War in Afghanistan The standard squad automatic weapon in Afghanistan was the M249 SAW with the PIP kit, which served alongside its heavier counterpart, the M240 machine gun. Most M249s were given a collapsible buttstock immediately prior to the invasion to reduce its length and make the M249 more practical for parachuting and close-quarters combat. Special Operations troops typically favored the shorter Para variant of the M249, which weighs much less.

A report entitled Lessons Learned in Afghanistan was released by Lieutenant Colonel Charlie Dean and SFC Sam Newland of the U.S. Army Natick Soldier Center in 2002. They found that 54% of SAW gunners had problems maintaining their M249s, and 30% reported that the gun rusted easily. Soldiers reported ammunition boxes rattling and falling off. 80% percent of soldiers surveyed were pleased with the light machine gun's accuracy and lethality, yet only 64% claimed they were "confident in their weapon". M249s clogging up with sand in the desert seems to be the main complaint.

Iraq War

The PIP and Para variants of the M249 SAW were used in the Iraq war since the invasion. By 2004, many M249s had been in service for almost 20 years and were becoming increasingly unreliable. Soldiers were requesting replacements and new features, and there are reports of soldiers holding their M249s together with duct tape. The lethality of the 5.56 mm ammunition has been called into question by reports of enemy soldiers still firing after being hit multiple times. As in previous conflicts, the sandy environment causes the M249s and other weapons to clog up and jam if they are not cleaned frequently.

The report Operation Iraqi Freedom – PEO Soldier Lessons Learned evaluates the performance of weapons in the Iraq War and was published by Lieutenant Colonel Jim Smith of the U.S. Army in May 2003. Smith spoke positively of the M249 SAW, claiming that it "provided the requisite firepower at the squad level as intended". He praised the SPW variant, noting that its "short barrel and forward pistol grip allowed for very effective use of the SAW in urban terrain". At the National Defense Industrial Association in 2007, Lieutenant Colonel Al Kelly of the 1st Battalion, 17th Infantry gave a presentation describing the M249 as having "good range, excellent reliability" and an "excellent tracer". He said that a cloth pouch was preferred over the plastic box for holding linked ammunition, and that "knock-down power is poor, but is compensated by rate of fire".

Evaluation