6-pounder gun or 6-pdr, usually denotes a gun firing a projectile weighing approximately . Guns of this type include: * QF 6 pounder Hotchkiss, a 57 mm naval gun of the 1880s; a similar weapon was designed by Driggs-Schroeder for the US Navy *Driggs-Schroeder Marks II and III and Driggs-Seabury M1898 and M1900 57 mm guns on mobile mounts, used by the US Army circa 1890–1920 * QF 6 pounder 6 cwt Hotchkiss, a British 57 mm tank gun of 1917 * QF 6 pounder Nordenfelt, a 57 mm naval gun of the 1880s very similar to the Hotchkiss * Ordnance QF 6-pounder, a British 57 mm anti-tank and tank gun of World War II * QF 6 pounder 10 cwt gun, a British twin mount naval and coast defence gun 1937–1956. Older types include: * Canon de 6 système An XI, a French 6-pounder muzzle-loading cannon of the Napoleonic era *

M1841 6-pounder field gun The M1841 6-pounder field gun was a bronze smoothbore muzzle-loading cannon that was adopted by the United States Army in 1841 and used from the Mexican–American War to the American Civil War. It fired a round shot up to a distance of at 5° e ...

, an American 6-pounder smoothbore muzzle-loading cannon of the mid-1800s

Guns denoted by calibre

Examples simply referred to by caliber include: * Bofors 57 mm gun family, including a WW2 field AT gun, a WW2 57 mm × 230 mm aircraft autocannon and a still-current family of three 57 mm x 438 mm naval artillery gun/anti air autocannons *

57 55 J The 57 55 J or ''57 mm, 55 caliber length model Jokinen coastal gun'' is a Finnish light coastal gun designed during the Continuation War. It the first coastal gun designed and manufactured completely in Finland and was intended to replace the o ...

, Finnish light coastal gun *

57 mm anti-tank gun M1943 (ZiS-2) The ZiS-2 (russian: ЗиС-2) (GRAU index: 52-P-271) is a Soviet Union, Soviet 57 mm anti-tank gun used during World War II. The ZiS-4 is a version of the gun that was meant to be installed in tanks. ''ZiS'' stands for ''Zavod imeni Stalina'' ( ...

, Soviet 57×480 mmR AT gun, also used on the ZiS-30 * Ho-401 cannon, Japanese prototype aircraft autocannon * Type 97 57 mm tank gun, Japanese tank cannon *Ch-51(M), used on the Soviet assault gun ASU-57 * AZP S-60, Soviet 57×347mmSR AA autocannon, also integrated into ZSU-57-2 Older types include: * 5.7 cm Maxim-Nordenfelt, short fortress gun of the 1880s

Guns denoted by calibre

See also