The J-1 tank gun was a tank gun which served as the main armament of the Black Mamba super-heavy tank, Earth's superweapon tank. The J-1 was basically the gun from the J-1 semi-autonomous proton cannon which had been removed from its original casing and had been modified for tank use, the size of the gun, and of the shells used by it, meant that the Black Mamba was a huge and extremely heavy tank, and had 2 loaders, since 2 loaders were needed to load the large, heavy shells onto a platform for the gun's rammer to push it into the barrel.