M249 light machine gun
Encyclopedia
The M249 light machine gun (LMG), previously designated the M249 Squad Automatic Weapon (SAW), and formally written as Light Machine Gun, 5.56 mm, M249, is an American version of the Belgian FN Minimi
, a light machine gun
manufactured by the Belgian
company FN Herstal (FN). The M249 is manufactured in the United States and is widely used by the U.S. Armed Forces
. The weapon was introduced in 1984 after being judged the most effective of a number of candidate weapons to address the lack of automatic
firepower in small units. The gun provides infantry squad
s with the heavy volume of fire
of a machine gun
combined with accuracy and portability approaching that of a rifle.
The M249 is gas operated and air-cooled. It has a quick-change barrel, allowing the gunner to rapidly replace an overheated or jammed barrel. A folding bipod
is attached near the front of the gun, though an M192 LGM
tripod is also available. It can be fed from both linked ammunition
and STANAG magazines, like those used in the M16
and M4
. This allows the SAW
gunner to use rifleman's magazines as an emergency source of ammunition in the event that he runs out of linked rounds. However, this will often cause malfunctions where the magazine spring has difficulty feeding rounds quickly enough to match the SAW's high cyclic rate.
M249s have seen action in every major conflict involving the United States since the 1989 invasion of Panama
. Soldiers are generally satisfied with the weapon's performance, though there have been reports of clogging with dirt and sand. Due to the weight and age of the weapon, the United States Marine Corps
is testing the M27 Infantry Automatic Rifle with plans to partially replace the M249 in Marine Corps service.
In 1965, the U.S. Army
and Marine Corps' primary machine guns were the M2 Browning and M60
. The M2 was a large-caliber heavy machine gun
, usually mounted on vehicles or in fixed emplacements. The M60 was a more mobile medium machine gun
intended to be carried with the troops to provide heavy automatic fire. Both were very heavy weapons and usually required a crew of at least two to operate efficiently. The Browning automatic rifle, 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 weapons 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
rifles had not been designed with sustained automatic fire in mind, they often overheated or jammed. The 30-round and 20-round magazines of these weapons also limited their sustained automatic effectiveness when compared to belt-fed weapons.
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. Through the 1960s, the introduction of a machine gun into the infantry squad was examined in various studies. While there was a brief flirtation with the concept of a flechette
- or dart-firing Universal Machine Gun during one study, most light machine gun experiments concentrated on the Stoner 63
light machine gun, a modular weapon which could be easily modified for different purposes. The Stoner 63 LMG saw combat for a brief period in Vietnam with the USMC, 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 caliber cartridges for the LMG did not appear until 1969. In July 1970, the U.S. Army finally approved development of an LMG, with no specified caliber. At this time, the nomenclature "Squad Automatic Weapon" (SAW) was introduced. Actual design of alternative cartridges for the LMG did not begin until July 1971. A month later, Frankford Arsenal
decided upon 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 that year. Prior to July 1972, SAW development contracts were awarded to Maremont, Philco Ford, and the Rodman Laboratory at Rock Island Arsenal
. These companies produced designs with Army designations XM233, XM234 and XM235 respectively—X denoting "experimental". Designs were required to have a weight of less than 9.07 kg (20 lb) including 200 rounds of ammunition, and a range of at least 800 meters (2,600 ft).
When the time came for developmental and operational testing of the SAW candidates, three 5.56 mm candidate weapons were included with the 6 mm candidates: the M16 HBAR
, a heavy-barrel variant of the M16 designed for prolonged firing; the Fabrique Nationale de Herstal
(FN) Minimi
; and the HK 23A1. The initial round of tests ended in December 1974. In February 1976, the Minimi and Rodman XM235 SAW were selected for further development. At this time, opinions of the 6 mm cartridge were beginning to sour due to the logistical implications of providing yet another ammunition type to the infantry. 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 HK 21A1 (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 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 weapon began in June 1981. The official adoption took place on February 1, 1982.
The new gun entered U.S. Army service as the M249 squad automatic weapon in 1984, and was adopted by the U.S. Marine Corps a year later. The U.S. production model has a different butt from that of the regular Minimi. It is manufactured in the FN factory in Columbia, South Carolina
.
Although found to be reliable and accurate, the M249 was considered to present unacceptable hazards in the form of an exposed hot barrel and sharp edges. There were also complaints that the front sight required special adjustment tools. On August 23, 1985, Undersecretary of the U.S. Army James R. Ambrose
suspended M249 production pending the development of the product improvement program (PIP) intended to fix these problems. Congress deleted funds for the M249 from the Fiscal Year 1986 defense budget, then retroactively set aside the program's prior year's funds from the M249 program for other purposes, including retirement and pay raises. 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 remaining 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. In 1994 the M249 squad automatic weapon was re-designated the M249 light machine gun.
The M249 is a belt-fed light machine gun. It fires the 5.56×45 mm NATO cartridge, usually a combination of one M856 tracer and four M855 ball cartridges fed from M27 linked belts
. Belts are typically held in a hard plastic or soft canvas box attached to the underside of the weapon.
It fires from an open bolt
and is gas operated. When the trigger is pulled, the bolt and bolt carrier move forward under the power of the recoil spring. A cartridge is stripped from the belt, chambered, and discharged, sending a bullet down the bore. Expanding propellant gases are diverted through a hole in the barrel into a chamber. This pressure moves a piston providing the energy to extract and eject the spent casing as well as advance the belt and compress the recoil spring, thus preparing for subsequent shots. At 1041 mm (41 in) long and 7.5 kg (17 lb) in weight (10 kg (22 lb) including a 200-round belt and plastic ammo box), the M249 is a cumbersome weapon.
The barrel has a rifling twist rate of one turn in 180 mm (7 in). Because firing heats up the bore, the air-cooled barrel is equipped with a mechanism to remove and replace the barrel assembly with a spare. A folding bipod with adjustable legs is attached near the front of the weapon, though there are provisions for hard-mounting to a M192 Lightweight Ground Mount
tripod or vehicle mount. The M249 provides accuracy approaching that of a rifle, combined with the sustained volume of fire of a machine gun. Its original gas regulator offered two different gas port sizes, allowing cyclic rates of fire of 750 rounds per minute (r/min) or 1,000 r/min. The latter setting was intended for adverse conditions such as an excessively dirty firearm or cold weather. The two-position gas regulator was discarded as part of a product improvement program. Sustained rate of fire, the rate of fire at which the gunner can fire continuously without overheating, is approximately 85 r/min.
M249 Para
M249 Special purpose weapon
Mk 46 Mod 0
Mk 48
The M249 LMG entered service in 1984 as the M249 SAW. Initial reactions to the gun were mixed: it fulfilled the light machine gun role well when fired from the ground, but was not as effective when fired from the shoulder or hip. It was praised for its extreme durability and massive firepower, though a number of areas for improvement were highlighted: the blank firing attachment fitted poorly, the bipod was very weak and broke easily, the sling attachment was awkward, and there were many slots and gaps which 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 heavily 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 weapons were donated to Bolivia
, Colombia
and Tunisia
.
Tactically, 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 usual load of ammunition carried for the weapon is 1,000 rounds in 5 200-round belts, although up to 500 extra rounds generally get loaded into 100 round soft boxes called nut sacks.
was still more common. Although exposure to combat was scarce, M249 gunners who were involved in fighting mainly used their weapons to provide cover fire for friendly maneuvering troops from fixed positions, rather than maneuvering with them. There were many complaints about the weapons clogging up with sand after prolonged use in the desert environment.
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 weapons, and 30% reported the gun rusted easily. Soldiers reported ammunition boxes rattling and falling off. 80% percent of soldiers surveyed were pleased with the weapon's accuracy and lethality, yet only 64% claimed they were "confident in their weapon". Weapons clogging up with sand in the desert seems to be the main complaint.
. By 2004, many M249s had been in service for almost twenty years and were becoming increasingly unreliable. Soldiers were requesting replacements and new features, and there are reports of soldiers holding their weapons 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 very regularly.
Operation Iraqi Freedom PEO Soldier Lessons Learned, a report on the performance of weapons in Iraq, was published by Lieutenant Colonel Jim Smith of the U.S. Army on May 15, 2003. Smith spoke positively of the M249, 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, LTC 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".
.
The Marine Corps is testing the M27 Infantry Automatic Rifle, a lighter, magazine-fed rifle to supplement and partially replace the M249. With plans to buy up to 4,100 IARs to complement and partially replace its 10,000 M249s (of which 8,000 will remain in service) held at platoon
level, it has acquired 450 of the Heckler & Koch HK416–based weapons for testing. The U.S. Army does not plan to introduce the IAR. Colonel Robert Radcliffe of the U.S. Army Infantry Research and Development Center stated that an automatic rifle with a magazine would lower the effectiveness and firepower of a squad. While the Marine Corps has 13-man squads, the Army organizes its soldiers into squads of nine and needs considerably more firepower from the squad machine gunners to make up the difference. The U.S. Army does, however, want to replace aging M249s with newer weapons.
The U.S. Army is currently working on replacing the M249's buttstock with a redesigned adjustable stock.
FN Minimi
The Minimi is a Belgian 5.56mm light machine gun developed by Fabrique Nationale in Herstal by Ernest Vervier. First introduced in 1974, it has entered service with the armed forces of over thirty countries...
, a light machine gun
Light machine gun
A light machine gun is a machine gun designed to be employed by an individual soldier, with or without an assistant, as an infantry support weapon. Light machine guns are often used as squad automatic weapons.-Characteristics:...
manufactured by the Belgian
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
company FN Herstal (FN). The M249 is manufactured in the United States and is widely used by the U.S. Armed Forces
United States armed forces
The United States Armed Forces are the military forces of the United States. They consist of the Army, Navy, Marine Corps, Air Force, and Coast Guard.The United States has a strong tradition of civilian control of the military...
. The weapon was introduced in 1984 after being judged the most effective of a number of candidate weapons to address the lack of automatic
Automatic firearm
An automatic firearm is a firearm that loads another round mechanically after the first round has been fired.The term can be used to refer to semi-automatic firearms, which fire one shot per single pull of the trigger , or fully automatic firearms, which will continue to load and fire ammunition...
firepower in small units. The gun provides infantry squad
Squad
In military terminology, a squad is a small military unit led by a non-commissioned officer that is subordinate to an infantry platoon. In countries following the British Army tradition this organization is referred to as a section...
s with the heavy volume of fire
Rate of fire
Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. It is usually measured in rounds per minute , or per second .-Overview:...
of a machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
combined with accuracy and portability approaching that of a rifle.
The M249 is gas operated and air-cooled. It has a quick-change barrel, allowing the gunner to rapidly replace an overheated or jammed barrel. A folding bipod
Bipod
A bipod is a support device that is similar to a tripod or monopod, but with two legs. It provides significant stability along two axes of motion .-Firearms:...
is attached near the front of the gun, though an M192 LGM
M192 Lightweight Ground Mount
The M192 Lightweight Ground Mount is a tripod fielded by the United States armed forces. It was designed and developed by Capco, Incorporated under contract through Picatinny Arsenal to replace the M122 tripod. The United States Army named the tripod one of 2005's top ten inventions...
tripod is also available. It can be fed from both linked ammunition
Belt (firearm)
A belt or ammunition belt is a device used to retain and feed cartridges into a firearm. Belts and the associated feed systems are typically employed to feed machine guns or other automatic weapons...
and STANAG magazines, like those used in the M16
M16 rifle
The M16 is the United States military designation for the AR-15 rifle adapted for both semi-automatic and full-automatic fire. Colt purchased the rights to the AR-15 from ArmaLite, and currently uses that designation only for semi-automatic versions of the rifle. The M16 fires the 5.56×45mm NATO...
and M4
M4 carbine
The M4 carbine is a family of firearms tracing its lineage back to earlier carbine versions of the M16, all based on the original AR-15 designed by Eugene Stoner and made by ArmaLite. It is a shorter and lighter variant of the M16A2 assault rifle, with 80% parts commonality.It is a gas-operated,...
. This allows the SAW
Squad automatic weapon
A squad automatic weapon is a weapon used to give infantry squads or sections a portable source of automatic firepower. Weapons used in this role are selective-fire rifles, usually fitted with a bipod and heavier barrel to perform as Light machine guns...
gunner to use rifleman's magazines as an emergency source of ammunition in the event that he runs out of linked rounds. However, this will often cause malfunctions where the magazine spring has difficulty feeding rounds quickly enough to match the SAW's high cyclic rate.
M249s have seen action in every major conflict involving the United States since the 1989 invasion of Panama
United States invasion of Panama
The United States Invasion of Panama, code-named Operation Just Cause, was the invasion of Panama by the United States in December 1989. It occurred during the administration of U.S. President George H. W...
. Soldiers are generally satisfied with the weapon's performance, though there have been reports of clogging with dirt and sand. Due to the weight and age of the weapon, the United States Marine Corps
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
is testing the M27 Infantry Automatic Rifle with plans to partially replace the M249 in Marine Corps service.
Development
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
and Marine Corps' primary machine guns were the M2 Browning and M60
M60 machine gun
The M60 is a family of American general-purpose machine guns firing 7.62×51mm NATO cartridges from a disintegrating belt of M13 links...
. The M2 was a large-caliber heavy machine gun
Heavy machine gun
The heavy machine gun or HMG is a larger class of machine gun generally recognized to refer to two separate stages of machine gun development. The term was originally used to refer to the early generation of machine guns which came into widespread use in World War I...
, usually mounted on vehicles or in fixed emplacements. The M60 was a more mobile medium machine gun
Medium machine gun
A medium machine gun or MMG, in modern terms, usually refers to a belt-fed automatic firearm firing a full-power rifle cartridge.-History:...
intended to be carried with the troops to provide heavy automatic fire. Both were very heavy weapons and usually required a crew of at least two to operate efficiently. The Browning automatic rifle, 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
M14 rifle
The M14 rifle, formally the United States Rifle, 7.62 mm, M14, is an American selective fire automatic rifle firing 7.62x51mm NATO ammunition. It was the standard issue U.S. rifle from 1959 to 1970. The M14 was used for U.S...
, which had a fully automatic mode. "Designated riflemen" in every squad were ordered to use their weapons 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
M16 rifle
The M16 is the United States military designation for the AR-15 rifle adapted for both semi-automatic and full-automatic fire. Colt purchased the rights to the AR-15 from ArmaLite, and currently uses that designation only for semi-automatic versions of the rifle. The M16 fires the 5.56×45mm NATO...
rifles had not been designed with sustained automatic fire in mind, they often overheated or jammed. The 30-round and 20-round magazines of these weapons also limited their sustained automatic effectiveness when compared to belt-fed weapons.
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. Through the 1960s, the introduction of a machine gun into the infantry squad was examined in various studies. While there was a brief flirtation with the concept of a flechette
Flechette
A flechette is a pointed steel projectile, with a vaned tail for stable flight. The name comes from French , "little arrow" or "dart", and sometimes retains the acute accent in English: fléchette.-Bulk and artillery use:...
- or dart-firing Universal Machine Gun during one study, most light machine gun experiments concentrated on the Stoner 63
Stoner 63
The Stoner 63, also known as the XM22/E1, is an American modular weapons system designed by Eugene Stoner in the early 1960s. It was produced by Cadillac Gage and used in very limited numbers in Vietnam by members of the United States Navy SEALs and several law enforcement...
light machine gun, a modular weapon which could be easily modified for different purposes. The Stoner 63 LMG saw combat for a brief period in Vietnam with the USMC, and later on a wider scale with the U.S. Navy SEALs
United States Navy SEALs
The United States Navy's Sea, Air and Land Teams, commonly known as Navy SEALs, are the U.S. Navy's principal special operations force and a part of the Naval Special Warfare Command as well as the maritime component of the United States Special Operations Command.The acronym is derived from their...
.
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 caliber cartridges for the LMG did not appear until 1969. In July 1970, the U.S. Army finally approved development of an LMG, with no specified caliber. At this time, the nomenclature "Squad Automatic Weapon" (SAW) was introduced. Actual design of alternative cartridges for the LMG did not begin until July 1971. A month later, Frankford Arsenal
Frankford Arsenal
The Frankford Arsenal was a United States Army ammunition plant located adjacent to the Bridesburg neighborhood of Northeast Philadelphia, Pennsylvania, north of the original course of Frankford Creek.-History:...
decided upon 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 that year. Prior to July 1972, SAW development contracts were awarded to Maremont, Philco Ford, and the Rodman Laboratory at Rock Island Arsenal
Rock Island Arsenal
The Rock Island Arsenal comprises , located on Arsenal Island, originally known as Rock Island, on the Mississippi River between the cities of Davenport, Iowa, and Rock Island, Illinois. It lies within the state of Illinois. The island was originally established as a government site in 1816, with...
. These companies produced designs with Army designations XM233, XM234 and XM235 respectively—X denoting "experimental". Designs were required to have a weight of less than 9.07 kg (20 lb) including 200 rounds of ammunition, and a range of at least 800 meters (2,600 ft).
When the time came for developmental and operational testing of the SAW candidates, three 5.56 mm candidate weapons were included with the 6 mm candidates: the M16 HBAR
Colt Automatic Rifle
Colt Automatic Rifle is a 5.56 mm NATO firearm offered by Colt Defense. It is based on the M16A2/A4, but features full automatic fire, an integrated bipod, and it can be configured to fire from an open bolt. The forward hand-grip has a distinctive squared off shape.It is one of many SAW-type...
, a heavy-barrel variant of the M16 designed for prolonged firing; the Fabrique Nationale de Herstal
Fabrique Nationale de Herstal
Fabrique Nationale d'Herstal — self identified as FN Herstal and often referred to as Fabrique Nationale or simply FN — is a firearms manufacturer located in Herstal, Belgium....
(FN) Minimi
FN Minimi
The Minimi is a Belgian 5.56mm light machine gun developed by Fabrique Nationale in Herstal by Ernest Vervier. First introduced in 1974, it has entered service with the armed forces of over thirty countries...
; and the HK 23A1. The initial round of tests ended in December 1974. In February 1976, the Minimi and Rodman XM235 SAW were selected for further development. At this time, opinions of the 6 mm cartridge were beginning to sour due to the logistical implications of providing yet another ammunition type to the infantry. 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
Ford Aerospace
Ford Aerospace & Communications Corp. was the aerospace and defense business of Ford Motor Company. It consisted of the Space Systems Division and the Western Development Labs .Partial company timeline:*1956 Aeronutronic becomes Ford Motor Company division.*1961 Ford Motor Company...
, and its designation was changed to XM248. A new M16 HBAR variant, the XM106, was developed in 1978, and soon after, Heckler & Koch
Heckler & Koch
Heckler & Koch GmbH is a German defense manufacturing company that produces various small arms. Some of their products include the SA80, MP5 submachine gun, G3 automatic rifle, the G36 assault rifle, the HK 416, the MP7 personal defense weapon, the USP series of handguns, and the high-precision...
lobbied to include a 5.56 mm conversion of its HK 21A1 (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 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 weapon began in June 1981. The official adoption took place on February 1, 1982.
The new gun entered U.S. Army service as the M249 squad automatic weapon in 1984, and was adopted by the U.S. Marine Corps a year later. The U.S. production model has a different butt from that of the regular Minimi. It is manufactured in the FN factory in Columbia, South Carolina
Columbia, South Carolina
Columbia is the state capital and largest city in the U.S. state of South Carolina. The population was 129,272 according to the 2010 census. Columbia is the county seat of Richland County, but a portion of the city extends into neighboring Lexington County. The city is the center of a metropolitan...
.
Although found to be reliable and accurate, the M249 was considered to present unacceptable hazards in the form of an exposed hot barrel and sharp edges. There were also complaints that the front sight required special adjustment tools. On August 23, 1985, Undersecretary of the U.S. Army James R. Ambrose
James R. Ambrose
James R. Ambrose was an aerospace executive who was United States Under Secretary of the Army from 1981 to 1988.-Biography:James R. Ambrose was born August 16, 1922, in Brewer, Maine. He was educated at the University of Maine, graduating in 1943...
suspended M249 production pending the development of the product improvement program (PIP) intended to fix these problems. Congress deleted funds for the M249 from the Fiscal Year 1986 defense budget, then retroactively set aside the program's prior year's funds from the M249 program for other purposes, including retirement and pay raises. 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 remaining 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. In 1994 the M249 squad automatic weapon was re-designated the M249 light machine gun.
Design details
M27 link
The M27 link, formally Link, Cartridge, Metallic Belt, 5.56mm, M27 is a disintegrating metallic bullet link issued by the United States armed forces and designed for use in belt-fed firearms. It holds 5.56x45mm NATO ammunition...
. Belts are typically held in a hard plastic or soft canvas box attached to the underside of the weapon.
It fires from an open bolt
Open bolt
A semi or full automatic firearm is said to fire from an open bolt if, when ready to fire, the bolt and working parts are held to the rear. When the trigger is pulled the bolt goes forward, feeding a round from the magazine into the chamber and firing it...
and is gas operated. When the trigger is pulled, the bolt and bolt carrier move forward under the power of the recoil spring. A cartridge is stripped from the belt, chambered, and discharged, sending a bullet down the bore. Expanding propellant gases are diverted through a hole in the barrel into a chamber. This pressure moves a piston providing the energy to extract and eject the spent casing as well as advance the belt and compress the recoil spring, thus preparing for subsequent shots. At 1041 mm (41 in) long and 7.5 kg (17 lb) in weight (10 kg (22 lb) including a 200-round belt and plastic ammo box), the M249 is a cumbersome weapon.
The barrel has a rifling twist rate of one turn in 180 mm (7 in). Because firing heats up the bore, the air-cooled barrel is equipped with a mechanism to remove and replace the barrel assembly with a spare. A folding bipod with adjustable legs is attached near the front of the weapon, though there are provisions for hard-mounting to a M192 Lightweight Ground Mount
M192 Lightweight Ground Mount
The M192 Lightweight Ground Mount is a tripod fielded by the United States armed forces. It was designed and developed by Capco, Incorporated under contract through Picatinny Arsenal to replace the M122 tripod. The United States Army named the tripod one of 2005's top ten inventions...
tripod or vehicle mount. The M249 provides accuracy approaching that of a rifle, combined with the sustained volume of fire of a machine gun. Its original gas regulator offered two different gas port sizes, allowing cyclic rates of fire of 750 rounds per minute (r/min) or 1,000 r/min. The latter setting was intended for adverse conditions such as an excessively dirty firearm or cold weather. The two-position gas regulator was discarded as part of a product improvement program. Sustained rate of fire, the rate of fire at which the gunner can fire continuously without overheating, is approximately 85 r/min.
| M1918 BAR Retired U.S. LMG |
M249 U.S. LMG |
M249 Para U.S. LMG |
M16A2 U.S. Service Rifle |
M240B U.S. MMG |
RPK-74 Russian LMG |
Negev IMI Negev The Negev is an Israeli 5.56 mm light machine gun, developed by Israel Military Industries Ltd. of Ramat HaSharon , as a replacement for the 5.56 mm Galil ARM light machine gun, whose barrel would overheat easily during sustained fire... Israeli LMG |
Ultimax 100 Ultimax 100 The Ultimax 100 is a Singaporean 5.56mm light machine gun, developed by the Chartered Industries of Singapore by a team of engineers under the guidance of American firearms designer L. James Sullivan. The gun is extremely accurate due to its low recoil.Work on a new light support weapon for the... Singaporean LMG |
|
|---|---|---|---|---|---|---|---|---|
| Weight loaded | 9.5 kg (21 lb) | 10 kg (22 lb) | 9.1 kg (20 lb) | 4 kg (9 lb) | 15.8 kg (35 lb) | 5.56 kg (12 lb) | 9.7 kg (21 lb) | 6.8 kg (15 lb) |
| Length | 1194 mm (47 in) | 1041 mm (41 in) | 893 mm (35 in) | 1000 mm (39 in) | 1245 mm (49 in) | 1060 mm (42 in) | 1020 mm (40 in) | 1030 mm (41 in) |
| Cartridge | 30-06 Springfield | 5.56×45 mm NATO | 5.56×45 mm NATO | 5.56×45 mm NATO | 7.62×51 mm NATO | 5.45×39 mm | 5.56×45 mm NATO | 5.56×45 mm NATO |
| Ammunition feed | 20-round box mag | 200-round belt | 200-round belt | 30-round box mag | 100-round belt | 45-round box mag | 150-round belt | 100-round drum |
| Muzzle velocity | 860 metre per second | 915 metre per second | 915 metre per second | 930 metre per second | 905 metre per second | 960 metre per second | 915 metre per second | 970 metre per second |
Variants
M249 PIP- The product improvement program kit replaced the original steel tubular stock with a plastic stock based upon the shape of the heavier M240 machine gun. The change in stocks allowed for the addition of a hydraulic buffer system to reduce recoil. In addition, the dual gas port settings were reduced to only one; variants with the product improvement kit can no longer fire at a higher cyclic speed. A handguard was added above the barrel to prevent burns, and the formerly fixed carrying handle was swapped for a folding unit. Certain parts were beveled or chamferChamferA chamfer is a beveled edge connecting two surfaces. If the surfaces are at right angles, the chamfer will typically be symmetrical at 45 degrees. A fillet is the rounding off of an interior corner. A rounding of an exterior corner is called a "round" or a "radius"."Chamfer" is a term commonly...
ed to prevent cutting soldiers' hands and arms. Other changes involved the bipod, pistol grip, flash suppressorFlash suppressorA flash suppressor, also known as a flash guard, flash eliminator, flash hider, or flash cone, is a device attached to the muzzle of a rifle or other gun that reduces the visible signature of the burning gases that exit the muzzle. This reduces the chances that the shooter will be blinded in dark...
, and sights. Over the years, additional modifications have been introduced as part of the Soldier Enhancement Program and Rapid Fielding Initiative. These include an improved bipod, 100 and 200 round fabric "soft pack" magazines (to replace the original plastic ammunition boxes), and picatinny railPicatinny railThe Picatinny rail or MIL-STD-1913 rail or STANAG 2324 rail or a "Tactical Rail" is a bracket used on some firearms in order to provide a standardized mounting platform. A similar system is the Weaver rail mount.-Description:...
s for the feed tray cover and forearm so that optics and other accessories may be added.
M249 Para
- The M249 Para is a compact version of the gun with a shorter barrel and sliding aluminum buttstock, so-called because of its intended use by airborne troops. It is much shorter and considerably lighter than the regular M249 at 893 mm (35 in) long and 7.1 kg (16 lb) in weight. The Army's Rapid Fielding Initiative is in the process of replacing the original collapsible buttstock with an adjustable model based loosely on the design of the M4 carbineM4 carbineThe M4 carbine is a family of firearms tracing its lineage back to earlier carbine versions of the M16, all based on the original AR-15 designed by Eugene Stoner and made by ArmaLite. It is a shorter and lighter variant of the M16A2 assault rifle, with 80% parts commonality.It is a gas-operated,...
buttstock.
M249 Special purpose weapon
- This lightweight and shorter version of the M249 is designed to meet USSOCOM special operations forces requirements. The carrying handle, magazine insertion well, and vehicle mounting lug all have been removed to reduce weight. As a result, the SPW cannot be mounted in vehicles or use M16 magazines. Picatinny rails were added to the feed cover and forearm for the mounting of optics, lasers, vertical foregrips, and other M4 SOPMODSOPMODThe Special Operations Peculiar MODification kit is an accessory system for the M4A1 carbine and FN SCAR Mk 16/17 used by USSOCOM...
kit accessories. The SPW also has a detachable bipod. The SPW's lightweight barrel is longer than that of the Para model, giving it a total length of 908 mm (36 in) and a weight of 5.7 kg (13 lb).
Mk 46 Mod 0
- This is a variant of the special purpose weapon adopted by USSOCOM. The program, which led to both the Mk 46 and Mk 48, was headed by the US Naval Special Warfare CommandUnited States Naval Special Warfare CommandThe United States Naval Special Warfare Command was commissioned on April 16, 1987, at Naval Amphibious Base Coronado in San Diego, California...
(NAVSPECWAR). Like the SPW, the carrying handle, magazine insertion well, and vehicle mounting lugs have been removed to save weight. However, the Mk 46 retains the standard M249 plastic buttstock instead of the collapsible buttstock used on the SPW. The Picatinny rail forearm also differs slightly from the SPW. The Mk 46 has the option of using the lighter SPW barrel or a thicker, fluted barrel of the same length.
Mk 48
- This is a 7.62×51 mm NATO7.62×51mm NATOThe 7.62×51mm NATO is a rifle cartridge developed in the 1950s as a standard for small arms among NATO countries...
version of the Mk 46, used by USSOCOM, when a heavier cartridge is required. It is officially classified as an LWMG (Light Weight Machine Gun) and was developed as a replacement for the Mk 43 Mod 0/1. The M60 based machine guns are a great deal more portable than the heavier M240 based designs used elsewhere in the US military in the infantry medium machine gun role. However the M60 based designs have a long history of insufficient reliability. Trials conducted through the mid-1990s led the US Army to replace its M60 with M240B GPMGs. The M240B however, weighs in at ~27.5 lb and is about 49" long with the standard barrel. NAVSPECWAR was reluctant to give up the increased portability of the M60 (~22.5 lb, 37.7" OAL with the shortest "Assault Barrel") designs in spite of the M240's increased reliability. A request was put in for a new machine gun in 2001, and FN responded with a scaled up version of the M249 weighing in at ~18.5 lb with an OAL of ~39.5". The new design achieved much better reliability than the M60-based weapons while bettering its light weight and maintaining the same manual of arms as the already in-use M249. USSOCOM was slated to begin receiving deliveries of the new gun in August of 2003.
Operational history
The M249 SAW was not used heavily before the 1991 Gulf War
Gulf War
The Persian Gulf War , commonly referred to as simply the Gulf War, was a war waged by a U.N.-authorized coalition force from 34 nations led by the United States, against Iraq in response to Iraq's invasion and annexation of Kuwait.The war is also known under other names, such as the First Gulf...
, though it has been used in every major U.S. conflict since. American personnel in Somalia in 1993, Bosnia
Bosnian War
The Bosnian War or the War in Bosnia and Herzegovina was an international armed conflict that took place in Bosnia and Herzegovina between April 1992 and December 1995. The war involved several sides...
in 1994, Kosovo
Kosovo War
The term Kosovo War or Kosovo conflict was two sequential, and at times parallel, armed conflicts in Kosovo province, then part of FR Yugoslav Republic of Serbia; from early 1998 to 1999, there was an armed conflict initiated by the ethnic Albanian "Kosovo Liberation Army" , who sought independence...
in 1999, Afghanistan
War in Afghanistan (2001–present)
The War in Afghanistan began on October 7, 2001, as the armed forces of the United States of America, the United Kingdom, Australia, and the Afghan United Front launched Operation Enduring Freedom...
in 2001 and Iraq since 2003 have been issued M249s. Surplus weapons were donated to Bolivia
Bolivia
Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...
, Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
and Tunisia
Tunisia
Tunisia , officially the Tunisian RepublicThe long name of Tunisia in other languages used in the country is: , is the northernmost country in Africa. It is a Maghreb country and is bordered by Algeria to the west, Libya to the southeast, and the Mediterranean Sea to the north and east. Its area...
.
Tactically, 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 usual load of ammunition carried for the weapon is 1,000 rounds in 5 200-round belts, although up to 500 extra rounds generally get loaded into 100 round soft boxes called nut sacks.
Gulf War
929 M249 SAWs were issued to personnel from the U.S. Army and USMC during the 1991 Gulf War, though the older M60 machine gunM60 machine gun
The M60 is a family of American general-purpose machine guns firing 7.62×51mm NATO cartridges from a disintegrating belt of M13 links...
was still more common. Although exposure to combat was scarce, M249 gunners who were involved in fighting mainly used their weapons to provide cover fire for friendly maneuvering troops from fixed positions, rather than maneuvering with them. There were many complaints about the weapons clogging up with sand after prolonged use in the desert environment.
Afghanistan
The standard squad automatic weapon in Afghanistan is the M249 with PIP kit, which serves alongside its heavier counterpart, the M240 machine gun. Almost every eight-man squad deployed is issued two M249s. Most M249s were given a collapsible buttstock immediately prior to the invasion to reduce length and make the weapons more practical for parachuting and close-quarters combat. Special Operations troops typically favor the shorter Para version of the weapon, 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
Natick Soldier Center
The U.S. Army Natick Soldier Research, Development and Engineering Center — also known as the U.S. Army Natick Soldier Center , or simply as Natick Labs — is an element of the United States Army Research, Development, and Engineering Command , headquartered at Aberdeen Proving Ground, Maryland,...
in 2002. They found that 54% of SAW gunners had problems maintaining their weapons, and 30% reported the gun rusted easily. Soldiers reported ammunition boxes rattling and falling off. 80% percent of soldiers surveyed were pleased with the weapon's accuracy and lethality, yet only 64% claimed they were "confident in their weapon". Weapons clogging up with sand in the desert seems to be the main complaint.
Iraq War
The PIP and Para versions of the M249 have also been used in the Iraq war since the invasion2003 invasion of Iraq
The 2003 invasion of Iraq , was the start of the conflict known as the Iraq War, or Operation Iraqi Freedom, in which a combined force of troops from the United States, the United Kingdom, Australia and Poland invaded Iraq and toppled the regime of Saddam Hussein in 21 days of major combat operations...
. By 2004, many M249s had been in service for almost twenty years and were becoming increasingly unreliable. Soldiers were requesting replacements and new features, and there are reports of soldiers holding their weapons 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 very regularly.
Operation Iraqi Freedom PEO Soldier Lessons Learned, a report on the performance of weapons in Iraq, was published by Lieutenant Colonel Jim Smith of the U.S. Army on May 15, 2003. Smith spoke positively of the M249, 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
National Defense Industrial Association
The National Defense Industrial Association is an association for the United States government and the defense industry. Based in Arlington, Virginia, NDIA was established in 1919 as a result of the inability of the defense industry to scale up the war effort during World War I...
in 2007, LTC Al Kelly of the 1st Battalion, 17th Infantry
17th Infantry Regiment (United States)
The 17th Infantry Regiment is a United States Army infantry regiment. While the 17th Infantry Regiment was organized on January 11, 1812, it was consolidated with the 3rd Infantry due to extremely heavy losses at Frenchtown, and lost its identity two years later until May 3, 1861, when it was...
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".
Future
Many of the M249s in U.S. Army and Marine Corps service have been worn down by continuous use and are becoming increasingly unreliable. A refurbishment program intended to extend the service lives of these M249s has been carried out, though the weapons are still deteriorating from heavy use. In particular, warping of the receiver rails is a nearly ubiquitous defect in heavily used first-generation M249s. This defect is no longer present on the current-issue M249, which has reinforced rails and full-length welding rather than spot weldingSpot welding
Spot welding is a process in which contacting metal surfaces are joined by the heat obtained from resistance to electric current flow. Work-pieces are held together under pressure exerted by electrodes. Typically the sheets are in the thickness range...
.
The Marine Corps is testing the M27 Infantry Automatic Rifle, a lighter, magazine-fed rifle to supplement and partially replace the M249. With plans to buy up to 4,100 IARs to complement and partially replace its 10,000 M249s (of which 8,000 will remain in service) held at platoon
Platoon
A platoon is a military unit typically composed of two to four sections or squads and containing 16 to 50 soldiers. Platoons are organized into a company, which typically consists of three, four or five platoons. A platoon is typically the smallest military unit led by a commissioned officer—the...
level, it has acquired 450 of the Heckler & Koch HK416–based weapons for testing. The U.S. Army does not plan to introduce the IAR. Colonel Robert Radcliffe of the U.S. Army Infantry Research and Development Center stated that an automatic rifle with a magazine would lower the effectiveness and firepower of a squad. While the Marine Corps has 13-man squads, the Army organizes its soldiers into squads of nine and needs considerably more firepower from the squad machine gunners to make up the difference. The U.S. Army does, however, want to replace aging M249s with newer weapons.
The U.S. Army is currently working on replacing the M249's buttstock with a redesigned adjustable stock.