Mod 3): Reliance-class cutter, , , , , future Heritage-class cutter See also Mark 38 25 mm Machine Gun System Oerlikon KBA 25 mm automatic cannon M230 30 mm automatic cannon Bushmaster II 30 mm chain gun Bushmaster III 35/50 mm chain gun Bushmaster IV 40 mm chain gun 30mm DS30M Mark 2 Automated Small Calibre Gun British automated mount with 30mm Bushmaster II List of weapons of the United States Marine Corps List of crew-served weapons of the U.S. Armed Forces References Notes Bibliography External links Northrop Grumman M242 Bushmaster Chain Gun Factsheet Federation of American Scientists: M242 NavWeaps.Com: 25 mm/87 (1") Mark 38 Machine Gun System U. S. Army Field Manual 3-22.1 Canadian-American Strategic Review: M242 Autocannon Vehicle weapons Cold War weapons of the United States Military equipment introduced in the 1980s 25 mm artillery United States Marine Corps equipment Alliant Techsystems Machine guns