Comments by "" (@neutronalchemist3241) on "MAC 1950: Disassembly & History" video.

  1. Those are .380 ACP, or 9mm short. A less powerful cartridge that was designed to be used with blowback designs. In theory, every cartridge can be fired by a simple blowback design, and 9mm lugers had been, and are, fired by blowback pistols (Astra 400, Hi Point...). But, in a blowback, the only thing that prevent the action to open too early (when there is too much pressure in the chamber, the walls of the cartridge are stuck to that of the chamber, and so to pull out the cartridge can cause a case rupture) is the weight of the bolt. The more powerful the cartridge, the heavier the bolt, and that means an heavier pistol, with an odd (top heavy) balance.
    1