The M2 .50 Cal is an automatic, belt-fed, recoil operated, air-cooled machine gun. Although it has a maximum range of 4.5 miles the .50 Cal was mostly effective within 1.2 miles when mounted atop the M3 tripod. As well as automatic fire the M2 could be operated in single shot mode, even being used as a sniper rifle during subsequent wars.
Despite it’s hard-hitting firepower the M2 has a relatively slow rate of fire (around 500-575 rounds per minute compared to the 1500 rpm the German MG42 could kick out). None the less the .50 Cal was very well considered and over 2,000,000 were produced during the course of the war and were used for infantry support on the M3 tripod, ground anti-aircraft role atop a tall tripod, and as primary or secondary weapon on tanks, armoured cars and light vehicles. It also served as anti-aircraft or primary/secondary weaponry on many different classes ships, and as primary weapons on US fighters such as the P51D Mustang or independently mounted defensive weaponry on bombers such as B17 Flying Fortresses.
The M2 .50 Cal is one of the most enduring pieces of modern day weaponry and can be found in service in many armies even today.