The M27 Infantry Automatic Rifle (IAR) is a lightweight, magazine-fed 5.56mm, select-fire weapon based on the Heckler & Koch HK416. It is used by the United States Marine Corps and is intended to enhance an automatic rifleman's maneuverability. The U.S. Marine Corps initially planned to purchase 6,500 M27s to replace a portion of the M249 light machine guns employed by automatic riflemen within Infantry and Light Armored Reconnaissance Battalions. Approximately 8,000–10,000 M249s will remain in s...