M231 heavy machine gun

The M231 heavy machine gun is a crew-served weapon employed by the UNSC armed forces for heavy fire-support and suppression. It is an air-cooled, gas-operated, belt-fed machine gun that fires 12.7x99mm high velocity rounds. It is most often seen mounted either on a tripod as part of a defensive emplacement, or on vehicles and aircraft such as the M313 "Elephant" HRV, M808 "Scorpion" Main Battle Tank, and D77 Pelican dropship.