Marines with Company A, Infantry Training Battalion, School of Infantry-West (SOI-West), fire the M2A1 .50 caliber heavy machine gun as part of their basic infantry training at Marine Corps Base Camp Pendleton, Calif. The M2A1 is the Marine Corps’ latest upgrade to the legacy M2 machine gun and enhances Marines’ lethality and survivability on the battlefield. The M2A1 modernizes the M2 with major changes, including set headspace and timing, a quick change barrel, and flash hider that reduces the weapon’s signature by 95 percent. (U.S. Marine Corps photo by Lance Cpl. Joseph A. Prado) - Marines with Company A, Infantry Training Battalion, School of Infantry-West (SOI-West), fire the M2A1 .50 caliber heavy machine gun as part of their basic infantry training at Marine Corps Base Camp Pendleton, Calif. The M2A1 is the Marine Corps’ latest upgrade to the legacy M2 machine gun and enhances Marines’ lethality and survivability on the battlefield. The M2A1 modernizes the M2 with major changes, including set headspace and timing, a quick change barrel, and flash hider that reduces the weapon’s signature by 95 percent. (U.S. Marine Corps photo by Lance Cpl. Joseph A. Prado)