 By 1990, the L / 44 was not considered powerful enough to deal with the future Soviet armour, which stimulated an effort by Rheinmetall to develop a better main armament. This first revolved around a 140-millimetre (5.5 in) tank gun named Neue Panzerkanone 140 ("new tank gun 140"), but later turned into a compromise which led to the development of an advanced 120 mm gun, the L / 55, based on the same internal geometry as the L / 44 and installed in the same breech and mount. The L / 55 is 1.3 metres (4.3 ft) longer, giving an increased muzzle velocity to ammunition fired through it. As the L / 55 retains the same barrel geometry, it can fire the same ammunition as the L / 44.
