How long is a 20mm round

Additional terms may apply for the media files. South Africa. United States. GIAT M Czech Republic. Rheinmetall Rh Russian Empire.

Japanese Empire. Hispano-Suiza HS. Colt Mk 12 cannon. Madsen 20 mm anti-aircraft cannon. Type 97 automatic cannon. Nazi Germany. The projectile configuration and the propellant are modified compared to the M55A2 version to better match specific operational users requirements. The 20 x mm Target Practice TP M55A2 cartridge is designed for use with the 20 mm M61 and M39 automatic guns, but it will function in other 20 mm weapons compatible with a cartridge case length of mm.

M61 guns on F aircraft and are compatible with M39 guns, automatic 20mm cannons mounted on fighter aircraft, helicopters and some ground-to-air defense systems. Projectiles or shells are typically 75 to mm 3—5 in long. Cartridges are typically 75 to mm 3—6 in long. Many but not all 20mm shells have an explosive filling and detonating fuze.

Like most cannon ammunition, 20mm caliber weapons are typically used against large targets such as vehicles, buildings, or aircraft. Though lethal against individual soldiers, 20mm ammunition is so large and heavy that its effects are inefficiently utilized on such relatively small targets. Cartridge type indicates the diameter of projectile and the length of the cartridge that holds it, for example 20x is a 20mm projectile in a mm long case.

Only rarely do two designers use the same case length, so this designation is usually definitive.