 Production of the German Leopard 2 and the new 120 mm tank gun began in 1979, fulfilling an order for the German Army. Although the American M1 Abrams was originally armed with the M68A1 105 mm gun (a version of the L7), the United States Army had planned to fit the tank with a larger main gun at a later date, and the tank's turret had been designed to accommodate a larger 120 mm gun. The larger gun was integrated into the M1A1 Abrams, with the first vehicle coming off the production line in 1985 The gun, known as the M256, was based on the L / 44 tank gun, although manufactured at Watervliet Arsenal and modified to increase the resistance of the barrels to fracture and fatigue. Tanks armed with versions of Rheinmetall's gun produced under licence include Japan's Type 90 and South Korea's K1A1. The gun had made a huge turn in technological history.
