Michigan-based Trijicon won an Army contract to build an optic for the vaunted “Ma Deuce,” and the sight has made its first appearance in the field.
First announced in July 2021, the Army tapped Trijicon to deliver its Machine Gun Reflex Sight, or MGRS, specifically for use with the M2A1 .50 caliber heavy machine gun. It basically looks like a huge RMR with a flip-in magnifier.
Constructed of 7075-T6 aluminum, the MGRS is designed to withstand the jarring, rapid recoil produced by fixed and turret-mounted machine guns. It features a large, non-magnified objective lens with a 35 MOA segmented circle reticle. Centered within the reticle is a 3 MOA dot for precise aiming. A single CR123A battery powers the unit, providing more than 1,000 hours of continuous operation. A three-power magnifier is included for faster positive identification (PID) of potential targets downrange. (Photo Trijicon)
Type classified as the M155 Mounted Machine Gun Optic, or MMO, the sight attaches to the M2A1 .50 cal with a BE Meyers BOARS Mount using M1913 Picatinny rails. (Photo: U.S. Army Capability Program Executive – Ground Soldier Systems)
“Compared with the original iron sights, the M155 MMO illuminates targets, especially when the environmental elements are not the best,” said Sgt. Eleanor Osgood, a mass communications specialist with the 126th TPASE. “The red-dot sight is very useful in ensuring the round hits the target.”
U.S. Army Sgt. Eleanor Osgood, assigned to the 126th Theater Public Affairs Support Element, Michigan Army National Guard, uses the M155 mounted machine gun optic to zero the M2 Browning machine gun at Camp Grayling, Michigan, June 9, 2026. (Photo: Staff Sgt. Patrick Mayabb/U.S. Army National Guard)
The MGRS offers seven brightness settings, two facilitating the use of night-vision optics and five settings for fast adjustment to match current conditions, including a super-bright setting for bright daylight. (Photo: Staff Sgt. Patrick Mayabb/U.S. Army National Guard)
Zeroing is via 1 MOA adjustment increments, and the sight has 100 MOA total travel of adjustment. The MGRS includes two interchangeable range knobs that are ballistically calibrated for use on M2 series. When properly zeroed to the weapon platform, the range knob allows the user to dial the correct range as a mechanical BDC for more accurate engagements. (Photo: Staff Sgt. Patrick Mayabb/U.S. Army National Guard)
Assorted telescopic, night vision, and thermal sights, such as this AN/PAS-13 optic seen in 2017, have been used on the M2 series over the years, as would be expected, as the Browning-designed heavy MG dates back to the 1920s. (Photo: Sgt. Heather Doppke/U.S. Army)
