Editing Automatic Colt Pistol (section)

{{Short description|Cartridge design used in semi-automatic pistols}}
[[File:380 ACP - FMJ - SB - 2.jpg|thumb|right|Rimless [[.380 ACP]] cartridge]]
'''Automatic Colt Pistol''' ('''ACP''') denotes various [[John Moses Browning]] [[Cartridge (firearms)|cartridge]] designs primarily used in [[Colt's Manufacturing Company|Colt]] and [[Fabrique Nationale de Herstal]] [[semi-automatic pistols]].<ref>{{cite book |last=Dockery|first=Kevin |title=Future Weapons |year=2007 |publisher=Berkley Trade |isbn=978-0-425-21750-4 |page=139 |quote=his agreement with Colt resulted in a number of cartridges being identified by the letters ACP, for Automatic Colt Pistol}}<!--|access-date=12 October 2010--></ref> All of these [[Cartridge (firearms)|cartridges]] are straight-sided and appear similar. The [[.32 ACP]], [[.38 ACP]], and [[.25 ACP]] are semi-rimmed and [[Headspace (firearms)|headspace]] on the rim, while the rimless [[.45 ACP]] and [[.380 ACP]] headspace on the mouth of the case.<ref name="wilson">Wilson, R. K. (1943). ''Textbook of Automatic Pistols''. Plantersville, SC: Small Arms Technical Publishing Company. pp. 229, 234, 241, 254, and 258.</ref>