105MM Tank Gun
The principal armament of the M1 Abrams model was the M68A1 105mm rifled tank gun. The gun was quickly upgraded because it did not fire nearly as far as originally detailed. The M1A1 and M1A2 now come equipped with a 120 mm smoothbore gun designed by Rheinmetall AG of Germany that can shoot a variety of rounds, including high-explosive, anti-tank warhead-shaped charge rounds. Watervliet Arsenal, New York, constructs the weapons.