page_title: Gunpowder
section_title: Sulfur-free gunpowder
hierarchical_section_title: Gunpowder / Sulfur-free gunpowder
caption_attribution_description: Deutsch: Geborstener Lauf der Replik einer Vorderladerpistole, der anstelle von Schwarzpulver mit Nitrocellulosepulver beschossen wurde und den erhöhten Belastungen des modernen Schießpulvers nicht standhielt. English: Catastrophically burst barrel of a muzzle loader pistol replica. During proofing the barrel was loaded with nitrocellulose powder instead of black powder. The barrel was not able to withstand the higher pressures of the modern propellant.
context_page_description: Gunpowder, also known as the retronym black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, charcoal, and potassium nitrate. The sulfur and charcoal act as fuels while the saltpeter is an oxidizer. Because of its incendiary properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms, artillery, rocketry, and pyrotechnics, including use as a blasting agent for explosives in quarrying, mining, and road building.
  Gunpowder was invented in 9th-century China as one of the Four Great Inventions, and spread throughout most parts of Eurasia by the end of the 13th century. Originally developed by the Taoists for medicinal purposes, gunpowder was first used for warfare around 904 AD.
  Gunpowder is classified as a low explosive because of its relatively slow decomposition rate and consequently low brisance. Low explosives deflagrate at subsonic speeds, whereas high explosives detonate producing a supersonic shockwave.
context_section_description: The development of smokeless powders, such as cordite, in the late 19th century created the need for a spark-sensitive priming charge, such as gunpowder. However, the sulfur content of traditional gunpowders caused corrosion problems with Cordite Mk I and this led to the introduction of a range of sulfur-free gunpowders, of varying grain sizes. They typically contain 70.5 parts of saltpeter and 29.5 parts of charcoal. Like black powder, they were produced in different grain sizes. In the United Kingdom, the finest grain was known as sulfur-free mealed powder (SMP). Coarser grains were numbered as sulfur-free gunpowder (SFG n): 'SFG 12', 'SFG 20', 'SFG 40' and 'SFG 90', for example; where the number represents the smallest BSS sieve mesh size, which retained no grains.
  Sulfur's main role in gunpowder is to decrease the ignition temperature. A sample reaction for sulfur-free gunpowder would be
  6 KNO₃ + C₇H₄O → 3 K₂CO₃ + 4 CO₂ + 2 H₂O + 3 N₂
caption: Burst barrel of a muzzle loader pistol replica, which was loaded with nitrocellulose powder instead of black powder and could not withstand the higher pressures of the modern propellant
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