M249 Squad Automatic Weapon

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M249 Squad Automatic Weapon

The M249 SAW
Type Light machine gun
Place of origin Flag of Belgium Belgium
Flag of the United States United States
Service history
Used by United States military
Production history
Manufacturer FN Herstal, FN Manufacturing
Unit cost US$4,087[1]
Variants See Variants
Specifications
Weight 16.5 lb empty
15.95 lb. (PARA model)
Length SAW:41 in

PARA: 36 in (stock extended), 30.5 in(stock compressed)

Barrel length 20.5 in (M249), 14.5 in (PARA model)

Cartridge 5.56x45mm NATO
Action Gas-operated, open bolt
Rate of fire 750 rounds/min
Muzzle velocity 915 meters/sec
Effective range 1000 m
Feed system
  • M27 disintegrating belts from 200-round plastic ammo box or 100/200-round reusable soft packs
  • Various STANAG Magazines.

The M249 Squad Automatic Weapon (M249 SAW) is the United States military designation for a sub-family of the FN Minimi squad automatic weapon (from Mini-mitrailleuse French: "mini-machine gun". Both are 5.56x45mm NATO light machine guns manufactured by Fabrique Nationale (FN) and its subsidiaries.

The Minimi is manufactured by Fabrique Nationale in Belgium, while the M249 is made by FNH USA, the American subsidiary of FN. The M249 was the winner of a competition carried out by the U.S. military in the late 1970s–early 1980s for a new squad automatic weapon. The Minimi has been adopted by many other countries since that time, especially among NATO members.

The M249 was one of many firearms fielded in the late 1970s, 1980s and 1990s that was part of the NATO adoption of a new smaller round. The Belgian cartridge (SS109), developed for use with the Minimi, was the winner of the competition for the new, standardized 5.56 mm round. In the United States, the M16A2 was adopted following the M249 as part of the move to this compatible, although different, round — firearms intended to fire the SS109 cartridge use a different rifling twist rate (1:7 inches) from the previous U.S. standard M193 5.56 mm cartridge.

The Minimi and the M249 are not exactly the same weapon — they weigh different amounts and have slightly different configurations; M249 variants can differ significantly. Although officially adopted in the early 1980s, some early production problems delayed full deployment until the turn of the decade. One thousand Minimis were purchased directly from FN for the Gulf War in 1991, as there were not enough M249s yet in service at the time. The M249 has undergone a number of variant and improvement programs, though it is scheduled to be replaced by a new lightweight machine gun — the AAI LMGA (2004 contract). In early 2005, U.S. Army ARDEC issued a solicitation for a new light machine gun; however, no selection was ever made.

Contents

[edit] Overview

The M249 is an air-cooled, gas-operated, fully-automatic-only firearm that fires from an open bolt position. It can accept belts of linked 5.56x45mm NATO (.223) ammunition through the top-mounted feed tray or M16-type magazines through the side-mounted port. The latter allows a SAW gunner to use riflemens' magazines in an emergency if he runs out of belted ammunition, though this often causes jams as the magazine spring cannot adequately keep up with the weapon's high rate of fire. Linked ammunition can be fed from either a loose belt or from a plastic box (6.92lb) (or cloth pouch) for 200 rounds, clipped under the receiver. The hard plastic box has issues with being insecurely attached and by producing noise with movement in its standard form. The M249 SAW features a built-in bipod and a tripod-mounting lug for supported fire, as well as a quick change barrel that helps prevent overheating during sustained fire. Barrels are engaged and disengaged by rotating the built-in handle, and a spare is normally carried slung in an "A-bag" by the gunner or his assistant. The forearm is designed to contain a small cleaning kit for field use, though it may not be stored there in practice.

US Marine Corps (USMC)fires a 5.56mm M249 Squad Automatic Weapons (SAW), during a live fire exercise conducted on the range at Al Jabbar, Air Base (AB), Kuwait, during Operation IRAQI FREEDOM.
US Marine Corps (USMC)fires a 5.56mm M249 Squad Automatic Weapons (SAW), during a live fire exercise conducted on the range at Al Jabbar, Air Base (AB), Kuwait, during Operation IRAQI FREEDOM.
A Marine fires blanks with the M15A2 BFA (Blank Firing Attachment) attached at the end of the barrel, in an exercise in 2001
A Marine fires blanks with the M15A2 BFA (Blank Firing Attachment) attached at the end of the barrel, in an exercise in 2001

The gun has good firepower for its size. The latest reports on failures of M249 SAW weapons in Iraq are sometimes attributed to the age of the weapons used, and sometimes to the dusty environment in Iraq and Afghanistan. Most of the current-issue M249s in U.S. Army are more than 10 years old, which is not excessively old for a service firearm, but can reduce reliability. There have been issues with its performance at other times, particularly earlier in its development.

For training exercises, the M249 is used with the M249 Blank Firing Adaptor (BFA), essentially a steel plug which screws into the muzzle and partially blocks it. (While standard blank firing adaptors for the M16 and M4 family of weapons will fit into the barrel of the M249 SAW, their use has been abandoned in favor of a SAW-specific BFA, due to the risk of catastrophic failure of the weaker rifle BFA, which is not durable enough for sustained automatic fire.) Gas-operated weapons rely on the projectile to trap gas pressure in the system as it leaves the barrel; without this, there will be insufficient pressure to cycle the weapon. U.S. M249s are sometimes fitted with the M145 MGO, a low-power optic that fits on via a top M1913 rail, when the rail is fitted. The regular M249 does not have a rail, however. The M249 mod kit increases the weight to 16.41 pounds.

United States military doctrine describes 3,600 m as the maximum range. Effective ranges include 800 m for a point target, 1000 m for an area target, and 600 m for suppression (suppression fire is attained by keeping the maximum height of the rounds no more than 1 m off the ground). Tracer ammunition burnout is at 900 m, however. The advised rates of fire are 85 rounds per minute with no barrel changes. With a barrel change every two minutes, this increases to 200 rounds per minute. For a barrel change every minute, the rate of fire can go up to 850 rounds per minute, which is approximately equal to the cyclic rate of fire, at about 850 to 900 round/min.

In addition to its traditional use as an infantry weapon, the M249 is also sometimes used as a vehicle-mounted weapon, most often on Humvees, either in the normal roof mounting (manually or remotely operated as part of a system such as the CROWS mount, sometimes in addition to heavier weapons such as an M2 Browning machine gun), or on a swing arm mounting accessible by the front passenger seat. It is also one of the weapons that can be mounted on the SWORDS robot.

[edit] M249 variants

U.S. Marine with an M249 PIP.
U.S. Marine with an M249 PIP.

[edit] M249 Para (M249E3)

The M249 Para is a commercial product (law enforcement and military sales only) by FNH USA, not a type classification. It features a metallic, retractable stock and a shorter barrel. It was designed as a paratrooper weapon, although its compact dimensions make it desirable in any combat scenario. The U.S. military did test a short-barreled variant based on a standard M249, but it would appear short-barreled M249s (not M249E4 SPWs or Mk 46 Mod 0s) have been modified to this standard in the field and are not original from factory. The difference between the FN M249 Para and the FN Minimi Para is the use of the so-called PIP (Product Improvement Program) kit developed for the M249, which is also found on all commercial M249 variants.

The following are U.S. military type classifications:

[edit] M249E4

The M249-based variant of the FN Minimi Special Purpose Weapon (SPW) has Picatinny rails mounted on the feed cover and handguard, a short barrel and a Para-style retractable stock. Some features from the SAW and Para models were removed to save weight — these include the STANAG magazine port, the tripod-mounting lug and the variable bipod.

[edit] Mk 46 Mod 0

Adopted by USSOCOM, the Mk 46 Mod 0 features an improved rail handguard and uses the standard fixed buttstock, which is significantly lighter than the E4's M5 retractable unit from FN. The Mk 46 variant differs notably from the M249 and Minimi in that it is only belt-fed, while the latter work with belts or M16-type magazines. The Mk 46 is lighter due to this change. While extremely similar, the Mk 46 Mod 0 and the M249E4 are not the same weapon.

See also: Mk 48 Mod 0

[edit] Minor variants and modifications

Many M249 SAWs have been modified to carry SPW-style Picatinny rails on the feed cover. This allows them to mount commercial day and night optical sights such as the M68 Aimpoint or low-magnification scopes. Additionally, early SAWs have fixed steel tubular stocks; the polymer stock pictured above was introduced with the PIP kit. Many M249s have been refitted with shorter Para-length barrels in the field, but there is nothing official to suggest these were received from the factory in this configuration.

All SAWs can mount the laser equipment needed to participate in a MILES combat simulation.

The weapon can also mount third-party suppressors. In particular, Gemtech manufactures suppressors designed to be mounted on NATO standard flash suppressors, such as the one used by most variants of the M249. In reality, however, this practice should be limited to responsible burst firing (as dictated in the M249 technical manual) since 5.56 mm ammunition is prone to soften, shed jackets, and destabilize when the host firearm is subjected to abusive firing schedules.

Variant Summary Table

Designation Description
XM249 5.56x45mm FN Minimi machine gun; SAW candidate
XM249E1/M249E1 XM249 variant; w/ 1:7-inch rifling; changes incorporated into standard M249
M249E2/M249 XM249/M249E1 variant; 5.56x45mm NATO FN Minimi machine gun variant w/ Product Improvement Program (PIP) kit improvements, including the heat shield; changes incorporated into standard M249
M249E3 5.56x45mm NATO FN Minimi Para machine gun variant; shorter barrel
M249E4 5.56x45mm NATO FN Minimi SPW machine gun; also incorporating PIP kit improvements
Mk 46 Mod 0 5.56x45mm NATO FN Minimi SPW/M249E4 machine gun variant; fixed buttstock and improved rail handguard.
Mk 46 Mod 1 5.56x45mm NATO FN Minimi SPW/M249E4 machine gun variant; fixed buttstock, an improved rail handguard and has a 200 round box magazine. Currently in service with certain USSOCOM units.

[edit] Feedback on the M249

The M249 placed on the M122 tripod.
The M249 placed on the M122 tripod.

On April 2002, A "Lessons Learned in Afghanistan" report by LTC Charlie Dean and SFC Sam Newland of the U.S. Army Natick Soldier Center was released. The report made the following comments about the M249:

  • 25% had engaged the enemy with their SAWs (personnel, bunkers, buildings, and vehicles).
  • 54% reported problems cleaning or maintaining their weapons.
  • 30% reported weapons easily rusting.
  • 80% of Soldiers were pleased with the weapon’s accuracy and lethality.
  • 64% of the Soldiers were confident in their weapon.
  • Soldiers reported ammunition drums falling off and rattling.

On 15 May 2003, An "Operation Iraqi Freedom PEO Soldier Lessons Learned" report by LTC Jim Smith, U.S. Army, was published. The report made the following comments on the M249:

M249 SAW: Overall positive comments on this weapon. It provided the requisite firepower at the squad level as intended. The short barrel and forward pistol grip allowed for very effective use of the SAW in urban terrain. Soldiers requested a better stowage position for the bipod legs. The legs interfered with the attachment of the forward pistol grip. If a pistol grip was attached and the legs were down, the legs made movement in the restrictive urban terrain difficult. Additionally, the soft ammo pouches are great improvements over the plastic ammo canister. However, the 100-round pouch performed much better than the 200-round pouch. There is a design flaw that allows the ammo to get tangled in the 200-round pouch.

In July 2005, Lieutenant General James N. Mattis, Commanding General, Marine Corps Combat Development Command, directed the Marine Corps Center for Lessons Learned to conduct a NCOs Lessons Learned Conference. Sixteen NCOs, all with combat leadership experience, attended the conference. On the M249, they commented:

The M249 squad automatic weapon had problems with the safety and lock mechanisms. It required a lot of maintenance, and there were too few spare barrels.

At the National Defense Industrial Association 2007, Colonel Al Kelly of the 1-17th Infantry Regiment (Stryker) gave a presentation that included the following comments on the 5.56 mm linked M249 SAW:

  • Good range
  • Reliability excellent
  • Cloth pouch preferred over plastic box
  • Tracer is excellent
  • Knock down power poor but compensated by rate of fire

[edit] M249 usage by other nations

In addition, the armed forces of several other nation use the FN Minimi and see that article for a list of users of the Minimi.

Marines from Marine Wing Support Group 37 fire the M249 Squad Automatic Weapon during a marksmanship competition held at Al Asad, Iraq in early 2005.
Marines from Marine Wing Support Group 37 fire the M249 Squad Automatic Weapon during a marksmanship competition held at Al Asad, Iraq in early 2005.

[edit] U.S. civilian purchases

The M249 was the first major machine gun which essentially no United States civilians are permitted to own in fully-automatic form. The reason is that importation of machine guns for private purchase was banned in 1968, and in 1986 it was made illegal for private persons to buy those manufactured in the United States after 1986. The M249 plant in South Carolina did not start producing them in earnest until the late 1980s due to early production problems. Transferable pre-1986 M249s do exist, but they are rare.

[edit] M249 in the media

In May 2006, the U.S. Army aired an unedited tape showing the then-leader of Al-Qaeda in Iraq, Abu Musab al-Zarqawi fumbling with the weapon, apparently needing assistance to operate the weapon and clear a malfunction. The video was widely seen by many US military personnel as an embarrassment to the late terrorist leader.

[edit] References

  1. ^ Squad Automatic Weapon (SAW), M249 Light Machine Gun

[edit] External links

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