The weapon has infinite ammo and the added protection of the fortifications behind which it is usually found. However, the turret imposes a limited firing arc, and one is exceedingly vulnerable from the lanes that the gun is unable to cover.
During Half-Life, Gordon Freeman is able to turn it against HECU soldiers, notably in the Black Mesa Transit System.
Enemies using the M-2 are easy to kill, as they are immobile while using it. A Mk 2 Grenade or a MP5 Grenade is enough to kill the enemy manning the weapon.
Presence of the machine gun usually indicates a likely wave of enemies; the machine gun should be manned as soon as possible.
The M-2 is extremely powerful, firing five rounds in the head or chest area are required to kill a H.E.C.U Marine most efficiently. However, constant awareness is required, the player should be ready to demount from the weapon as soon as they are overrun or attacked from behind.
HECU troops at the rocket launch site, with an M2 nearby.
Barney killing HECU soldiers with an M2 in the Freight Yard.