The Magnum Research Mark XIX is a semi-automatic pistol chambered in .50 Action Express. It runs on a gas-operated, rotating-bolt action, a design more common to rifles than to handguns, which lets it cycle a large-bore magnum pistol cartridge that would tax a typical blowback or tilting-barrel handgun action. This example is finished in brushed chrome for a bright, polished look on the slide and frame.