The cartridge was developed in
Nazi Germany during
World War II as a necked-up 20 mm variant of the 15×96mm cartridge in use with the
MG 151/15 heavy aircraft machinegun. The 15 mm caliber proved to be insufficient for aircraft use and it was thus decided to redevelope the cartridge into 20 mm caliber, by shortening and necking-up the casing, and installing the 20 mm
mine shells of the
MG FF/M. By necking up the existing cartridge, the MG 151/15 guns could easily be converted by a barrel switch, creating the
MG 151/20. Beyond the MG 151/20, the 20×82mm was also used in the
MG 210 cannon, an attempt by Mauser to improve on the rate of fire of their MG 151 while making it lighter and simpler, as well as the French post-war
MG 250 cannon by
Atelier Mécanique de Mulhouse. South Africa then went on to both produce and further develop the MG 151 as the
Vektor GA-1, as well as the 20×82mm, later on adopting the cartridge for the
Denel NTW-20 anti-material rifle in the 1990s. == Cartridges ==