Cordite

Cordite is a family of smokeless propellants developed and produced in Britain since 1889 to replace black powder as a military firearm propellant. Cordite is made by combining two chemical explosives—nitrocellulose and nitroglycerine—with petroleum jelly. It is designed, in normal use, to produce a subsonic deflagration wave rather than the supersonic detonation wave produced by brisants, or high explosives. The hot gases produced by burning gunpowder or cordite generate sufficient pressure to propel a bullet or shell to its target, but not so quickly as to damage the gun barrel. Cordite was used initially in the .303 British, Mark I and II, standard rifle cartridge between 1891 and 1915. Shortages of cordite in World War I led to the creation of the HM Factory, Gretna on the English–Scottish border, which produced around 800 tons of cordite per week. The UK also imported some United States–developed smokeless powders for use in rifle cartridges. Cordite was also used for large weapons, such as tank guns, artillery, and naval guns. It has been used mainly for this purpose since the late 19th century by the UK and British Commonwealth countries. Its use was further developed before World War II, and as 2-and-3-inch-diameter (51 and 76 mm) Unrotated Projectiles for launching anti-aircraft weapons. Small cordite rocket charges were also developed for ejector seats made by the Martin-Baker Company. Cordite was also used in the detonation system of the Little Boy atomic bomb dropped over Hiroshima in August 1945. During World War II, double-base propellants were very widely used, and there was some use of triple-base propellants by artillery. Triple-base propellants were used in post-war ammunition designs and remain in production for UK weapons; most double-base propellants left service as World War II stocks were expended after the war. For small arms it has been...