.45 ACP

From Gunpedia

The .45 ACP is a large caliber Rimless handgun, and Submachine gun cartridge, it has been in Service since World War I, and saw Popularity when it was utilized in the Thompson submachine gun, the prime SMG used by US Militaries, Law Agencies, and Gangsters, which made it Infamous amongst civilians, it has also been used in several Handguns, although it is not as Long, or Powerful as the .44 Magnum cartridge, it is larger in Diameter, overall the .45 ACP is probaly one of the most utilized Pistol cartridges, beside the 9 mm Parabellum/Luger.