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Photo Information

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)

Photo by Ashley Calingo

M2A1 machine gun improves Marines’ lethality, survivability

26 Apr 2017 | Ashley Calingo, MCSC Office of Public Affairs and Communication Marine Corps Systems Command

Marine Corps Systems Command is equipping Marines with the updated M2A1 .50-caliber machine gun, increasing Marines’ survivability and lethality on the battlefield.

The M2A1 serves as an upgrade to the legacy M2 machine gun currently used by Marines across the Corps. The updated M2A1 is easier and safer to use due to three major changes: a quick-change barrel, fixed headspace and timing, and a flash hider that reduces the weapon’s signature by 95 percent at night.

“M2s are the most reliable heavy machine gun,” said Maj. Harry Thompson, team lead for General Purpose Weapons at MCSC. “The improved M2A1 makes Marines more lethal because they’re able to get rounds down range quicker. Marines will have better mobility because of the fixed headspace and timing—it’s much quicker to move the gun from position to position and put it back into action. Because they’re less exposed, Marines will have better survivability too.”

The current M2 requires Marines to manually set headspace and timing before firing, after assembly, and after required barrel changes when the barrel becomes extremely hot from high volumes of fire. “Headspace” is the distance between the face of the bolt and the base of the cartridge case when it is fully seated in the chamber. “Timing” is the adjustment of the gun so that firing takes place when the recoiling parts are in the correct position for firing.

Correct adjustments of both are necessary for the gun to work properly and continue to work; improper adjustments can lead to malfunctions that could potentially injure the user or damage the weapon. Fixed headspace and timing reduces operator risk and eliminates the need for Marines to master and execute this time-consuming procedure.

The fixed headspace and timing on the M2A1 enables the machine gun’s second major improvement—the quick-change barrel, said Thompson.

“Marines no longer have to manually screw the barrel in to set the headspace,” he said. “Instead, the barrel pops into the receiver and locks in place quickly, similar to the M240B machine gun.”

Having a quick-change barrel improves Marines’ readiness by reducing the amount of time they are exposed to enemy fire and shortens the amount of time the weapon is out of operation. By spending less time manually adjusting headspace and timing settings, and having the ability to change the M2A1’s barrel quickly, Marines can respond faster and more efficiently to enemy fire.

The third major improvement is the flash hider at the end of the barrel, said Thompson. By significantly reducing muzzle flash, Marines can better mask their position in firefights. The flash hider also limits white-out conditions caused by the brilliance of the weapon firing, enabling Marines to use night vision devices more effectively.

“All in all, MCSC will be fielding around 3,600 M2A1s to Marines,” said Kelly Sullivan, a program analyst for General Purpose Weapons at MCSC. “We completed Phase I fielding in March 2017, which covered infantry units, the majority of infantry-like units and infantry Reserves. We’re currently starting Phase II, which should run through the end of May.  The fielding process will be will be finished during FY18.”

The M2A1 is one of the many capabilities acquired and managed by MCSC’s Infantry Weapons Systems. For more news on IWS, click here.
Marine Corps Systems Command