MDM 2011: M27 contract awarded by USMC

The M27 Infantry Automatic Rifle (IAR) 5.56 mm machine gun, a variant of the Heckler & Koch (HK) HK416, has been officially selected by the USMC to replace the M249 light machine guns currently employed by riflemen within Infantry and Light Armored Reconnaissance Battalions.

The award of a Full Rate Production contract on 15 September was made after the successful conclusion of a Limited User Trial of the M27 by the USMC this summer. The service is planning to purchase between 4,500 and 6,500 IARs to replace some 2,000 M249s currently in use. A company official told Shephard that the current contract is for 3,638 weapons.

The IAR programme began in 2001 as a ‘needs statement’ within the USMC. Operational experience in Iraq and Afghanistan reinforced the requirement for a magazine-fed 5.56 mm automatic rifle designed to be operated by a single marine and possessing greater accuracy, increased reliability, and lighter weight than the existing belt-fed 5.56 mm machine gun.

After an assessment looking at the offers of six companies including FN USA and Colt, HK was selected to provide a variant of the HK416 in mid-2010 for test and evaluation. The company was awarded a Low Rate Initial Production (LRIP) order for approximately 500 systems for initial training, limited fielding, and selected marine infantry unit/user assessments, which it delivered in November 2010.

The M27 has a 16.5 inch barrel, a Trijicon ACOG 3.5x35 Squad automatic-weapon Day Optic  with  R.M.R. and LaRue tactical quick detachable mount, and 11-inch quad one-piece Picatinny free floating rail system.

The M27 uses an HK proprietary gas system instead of the normal gas impingement system (gas tube) found on most M4/M16-type weapons. The HK system employs a piston driving an operating rod to control the function of the bolt, preventing propellant gases and the associated carbon fouling from entering the weapon’s interior. This increases the reliability of the weapon, reduces operator cleaning time, minimises heat transfer to the bolt and bolt carrier; and lessens wear and tear on critical components.