Infantry Automatic Rifle
Encyclopedia
The M27 Infantry Automatic Rifle (IAR) is the name given to a lightweight, magazine-fed 5.56mm weapon sought by the United States Marine Corps
, which is intended to enhance the automatic rifleman's maneuverability and displacement speed. The Marine Corps is planning to purchase 4,476 IARs to replace 2,000 M249 light machine gun
s currently employed by automatic riflemen within Infantry and Light Armored Reconnaissance
Battalions. Approximately 8,000–10,000 M249s will remain in service at the company level to be used at the discretion of company commanders. The United States Army
does not plan to purchase the IAR.
), Heckler & Koch
(with a variant of the HK416), and Colt Defense
, which provided two competing designs. Companies that attempted to compete but were not accepted as finalists for testing include Land Warfare Resources Corporation
, which competed with the M6A4 IAR, Patriot Ordnance Factory, and General Dynamics Armament and Technical Products
with the CIS Ultimax 100 MK5
(marketed as the GDATP IAR). In December 2009, the Heckler & Koch model beat out the other three finalists, and has entered the final five months of testing. It was designated as the M27 in the summer of 2010, coincidentally sharing a designation with the M27 link
it would not use.
While Marine Corps Systems Command
is optimistic about operational testing, former Commandant of the Marine Corps
General
James T. Conway
remains skeptical that the reduced firepower at the fireteam
-level is a viable option. Though he has authorized funding to test 450 of the weapons, the program will have to get his approval before full production can be funded. After the Marine Corps Operational Test and Evaluation Activity
supervised a round of testing at MCAGCC Twentynine Palms
, Fort McCoy
, and Camp Shelby
(for dust, cold-weather, and hot-weather conditions, respectively), limited fielding began for 458 IARs to four infantry battalions (one per each Marine Expeditionary Force
and one reserve
) and one light armored reconnaissance
battalion; all are slated to deploy to Afghanistan in 2011.
In May 2011, General James Amos of the Marine Corps approved the termination of a Limited User Evaluation (LUE), and the replacement of the M249 LMG by the M27. Fielding of the approximately 4,500 M27 units is expected to complete in Summer 2013, for a cost of $13 million. M27 gunners will be equipped with around 22 of the 30-round magazines already in use with the M16
and M4 Carbine
. Twenty-two magazines will approximate the prescribed individual combat load of a M249 SAW gunner, and although the M27 gunner is not expected to carry all 22 magazines, they are provided to the units so that a determination can be made at the unit level on what the individual combat load should look like. It will undoubtedly vary by unit, based on the evaluations conducted by the four infantry battalion and one light armored reconnaissance battalion that were issued quantities of the M27 for the LUE. Though program officials are aware that switching from the belt-fed M249 will result in a loss of suppressive fire
capabilities, Charles Clark III, of the Marine Corps' Combat Development and Integration office cites the substantial increased accuracy of the M27 as a significant factor in replacing the M249.
The notion that the M27 represents a reduction in suppressive fire has spawned considerable debate among proponents of the M249 SAW within the infantry, and those who advocate that a lighter, more maneuverable, and accurate weapon is sufficient to support offensive operations at the squad level. It is debatable, in fact, that program officials actually concede a loss of suppressive fire capabilities, as the only statements of concern over this concept were made by General Conway.
and Heckler & Koch G36
. It features a gas-operated short-stroke piston action
(instead of the traditional direct impingement
) with a rotating bolt
. The weapon also fires from a closed bolt unlike many traditional machine guns. It is modified with a heavier barrel and includes a bayonet lug
. The free-floating barrel
is surrounded by MIL-STD-1913 Picatinny rails
for use with accessories and optics. It draws ammunition from any standard STANAG magazine
.
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...
, which is intended to enhance the automatic rifleman's maneuverability and displacement speed. The Marine Corps is planning to purchase 4,476 IARs to replace 2,000 M249 light machine gun
M249 light machine gun
The M249 light machine gun , previously designated the M249 Squad Automatic Weapon , 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 . The M249 is manufactured in the...
s currently employed by automatic riflemen within Infantry and Light Armored Reconnaissance
United States Marine Corps Light Armored Reconnaissance
The United States Marine Corps Light Armored Reconnaissance Battalions, or LAR Battalions, are fast and mobilized armored terrestrial reconnaissance units that conduct reconnaissance-in-force ahead of the battalion landing teams or division infantry forces...
Battalions. Approximately 8,000–10,000 M249s will remain in service at the company level to be used at the discretion of company commanders. The United States Army
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...
does not plan to purchase the IAR.
History
The Infantry Automatic Rifle program began in 2005, when the Marine Corps sought information from manufacturers. In 2006, contracts were issued for sample weapons to Fabrique Nationale d'Herstal (providing an IAR variant of the FN SCARFN SCAR
The Special Operations Forces Combat Assault Rifle, or SCAR, is a modular rifle made by FN Herstal for the United States Special Operations Command to satisfy the requirements of the SCAR competition. This family of rifles consist of two main types...
), 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...
(with a variant of the HK416), and Colt Defense
Colt Defense
Colt Defense LLC, together with its subsidiaries, is a designer, developer and manufacturer of small arms weapons systems for individual soldiers and law enforcement personnel. It is headquartered in West Hartford, Connecticut...
, which provided two competing designs. Companies that attempted to compete but were not accepted as finalists for testing include Land Warfare Resources Corporation
Land Warfare Resources Corporation
LWRC, formerly known as Leitner-Wise Rifle Company, Inc. and Land Warfare Resources Corporation, is a CAGE defense contractor and firearms manufacturer, founded in 1999, and based in Cambridge, Maryland. From 1999 to January 2006, the company was primarily engaged in research and development. In...
, which competed with the M6A4 IAR, Patriot Ordnance Factory, and General Dynamics Armament and Technical Products
General Dynamics
General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...
with the CIS Ultimax 100 MK5
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...
(marketed as the GDATP IAR). In December 2009, the Heckler & Koch model beat out the other three finalists, and has entered the final five months of testing. It was designated as the M27 in the summer of 2010, coincidentally sharing a designation with the M27 link
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...
it would not use.
While Marine Corps Systems Command
Marine Corps Systems Command
Marine Corps Systems Command is located at MCB Quantico.-Mission:Serve as the Commandant's principal agent for acquisition and sustainment of systems and equipment used by the operating forces to accomplish their warfighting mission....
is optimistic about operational testing, former Commandant of the Marine Corps
Commandant of the Marine Corps
The Commandant of the Marine Corps is normally the highest ranking officer in the United States Marine Corps and is a member of the Joint Chiefs of Staff...
General
General (United States)
In the United States Army, United States Air Force, and United States Marine Corps, general is a four-star general officer rank, with the pay grade of O-10. General ranks above lieutenant general and below General of the Army or General of the Air Force; the Marine Corps does not have an...
James T. Conway
James T. Conway
James Terry Conway is a retired United States Marine Corps four-star general who was the 34th Commandant of the Marine Corps...
remains skeptical that the reduced firepower at the fireteam
Fireteam
A fireteam is a small military unit of infantry. It is the smallest unit in the militaries that use it and is the primary unit upon which infantry organization is based in the British Army, Royal Air Force Regiment, Royal Marines, United States Army, United States Marine Corps, United States Air...
-level is a viable option. Though he has authorized funding to test 450 of the weapons, the program will have to get his approval before full production can be funded. After the Marine Corps Operational Test and Evaluation Activity
Marine Corps Operational Test and Evaluation Activity
Marine Corps Operational Test and Evaluation Activity is the independent Operational Test and Evaluation authority for the U.S. Marine Corps...
supervised a round of testing at MCAGCC Twentynine Palms
Marine Corps Air Ground Combat Center Twentynine Palms
The Marine Corps Air Ground Combat Center , also known as 29 Palms, is a United States Marine Corps base. It was a census-designated place officially known as Twentynine Palms Base located adjacent to the city of Twentynine Palms in southern San Bernardino County, California. As of the 2000...
, Fort McCoy
Fort McCoy, Wisconsin
Fort McCoy is an active United States Army installation. It is located on 60,000 acres between Sparta and Tomah, Wisconsin, in Monroe County...
, and Camp Shelby
Camp Shelby
Camp Shelby is a military post whose North Gate begins at the southern boundary of Hattiesburg, Mississippi, on United States Highway 49. It is the largest state owned training site in the nation. During wartime, the camp's mission is to serve as a major, independent mobilization station of the...
(for dust, cold-weather, and hot-weather conditions, respectively), limited fielding began for 458 IARs to four infantry battalions (one per each Marine Expeditionary Force
Marine Expeditionary Force
A Marine Expeditionary Force or MEF is the largest type of a Marine Air-Ground Task Force...
and one reserve
United States Marine Corps Reserve
The Marine Forces Reserve is the reserve force of the United States Marine Corps. It is the largest command in the U.S...
) and one light armored reconnaissance
United States Marine Corps Light Armored Reconnaissance
The United States Marine Corps Light Armored Reconnaissance Battalions, or LAR Battalions, are fast and mobilized armored terrestrial reconnaissance units that conduct reconnaissance-in-force ahead of the battalion landing teams or division infantry forces...
battalion; all are slated to deploy to Afghanistan in 2011.
In May 2011, General James Amos of the Marine Corps approved the termination of a Limited User Evaluation (LUE), and the replacement of the M249 LMG by the M27. Fielding of the approximately 4,500 M27 units is expected to complete in Summer 2013, for a cost of $13 million. M27 gunners will be equipped with around 22 of the 30-round magazines already in use with 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 Carbine
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,...
. Twenty-two magazines will approximate the prescribed individual combat load of a M249 SAW gunner, and although the M27 gunner is not expected to carry all 22 magazines, they are provided to the units so that a determination can be made at the unit level on what the individual combat load should look like. It will undoubtedly vary by unit, based on the evaluations conducted by the four infantry battalion and one light armored reconnaissance battalion that were issued quantities of the M27 for the LUE. Though program officials are aware that switching from the belt-fed M249 will result in a loss of suppressive fire
Suppressive fire
In military science, suppressive fire is a fire that degrades the performance of a target below the level needed to fulfill its mission. Suppression is usually only effective for the duration of the fire. Suppressive fire is not always a direct form of fire towards targets; it can be an effective...
capabilities, Charles Clark III, of the Marine Corps' Combat Development and Integration office cites the substantial increased accuracy of the M27 as a significant factor in replacing the M249.
The notion that the M27 represents a reduction in suppressive fire has spawned considerable debate among proponents of the M249 SAW within the infantry, and those who advocate that a lighter, more maneuverable, and accurate weapon is sufficient to support offensive operations at the squad level. It is debatable, in fact, that program officials actually concede a loss of suppressive fire capabilities, as the only statements of concern over this concept were made by General Conway.
Design
The M27 is based on the Heckler & Koch HK416, which in turn derives from the M4 carbineM4 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,...
and Heckler & Koch G36
Heckler & Koch G36
The Heckler & Koch G36 is a 5.56×45mm assault rifle, designed in the early 1990s by Heckler & Koch in Germany as a replacement for the 7.62mm G3 battle rifle. It was accepted into service with the Bundeswehr in 1997, replacing the G3...
. It features a gas-operated short-stroke piston action
Firearm action
In firearms terminology, an action is the physical mechanism that manipulates cartridges and/or seals the breech. The term is also used to describe the method in which cartridges are loaded, locked, and extracted from the mechanism. Actions are generally categorized by the type of mechanism used...
(instead of the traditional direct impingement
Direct impingement
Direct impingement is a type of gas operation for a firearm that directs gas from a fired cartridge directly to the bolt carrier or slide assembly to cycle the action.- Evaluation :...
) with a rotating bolt
Rotating bolt
Rotating bolt is a method of locking originally developed by Ferdinand Ritter von Mannlicher and found in his Steyr-Mannlicher M1895 straight-pull bolt-action rifle designed for and issued to the Austro-Hungarian Army...
. The weapon also fires from a closed bolt unlike many traditional machine guns. It is modified with a heavier barrel and includes a bayonet lug
Bayonet lug
A bayonet lug is a standard feature on most military muskets, rifles, and shotguns, and on some civilian longarms. It is intended for attaching a bayonet, which is typically a long spike or thrusting knife...
. The free-floating barrel
Free-floating barrel
A free-floating barrel is a specific design technology used in highly accurate rifles, particularly match grade rifles, to increase the accuracy of the weapon.With normal rifles, the barrel rests in contact with the stock...
is surrounded by MIL-STD-1913 Picatinny rails
Picatinny rail
The 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:...
for use with accessories and optics. It draws ammunition from any standard STANAG magazine
STANAG magazine
A STANAG magazine is a type of detachable firearm magazine proposed by NATO in October 1980. Shortly after NATO's acceptance of the 5.56x45mm NATO rifle cartridge, Draft Standardization Agreement 4179 was proposed in order to allow the military services of member nations easily to share rifle...
.