What cartridge, also known as 9 mm Luger by the C.I.P. or 9 mm NATO by NATO, is used in the submachine gun the MP 40?
9×19mm Parabellum The 9×19mm Parabellum, also known as 9 mm Luger by the C.I.P. or 9 mm NATO by NATO (abbreviated 9mm, 9mmP, 9×19mm or 9×19) is a cartridge that was designed by Georg Luger and introduced in 1902 by the German weapons manufacturer Deutsche Waffen und Munitionsfabriken (DWM) (German Weapons and Munitions Factory) for their Luger semi-automatic pistol.
M56 Submachine gun The M56 submachine gun is a Yugoslavian submachine gun chambered in 7.62×25mm Tokarev, designed for use with the Yugoslav People's Army. Initially a state-funded product, it was later produced by Zastava Arms and saw use in a number of conflicts following the breakup of former Yugoslavia. The M56 is a clone of the MP 40 submachine gun used by Nazi Germany, easily distinguished from the MP 40 by its increased length and curved magazine.