Gunpowder is also known more commonly as black powder, was the first widely used propellant in muzzleloaders. Black powder is a granular mixture of a nitrate, typically potassium nitrate (KNO3), which supplies oxygen for the reaction; charcoal, which provides carbon and other fuel for the reaction, simplified as carbon (C); sulfur (S), which, while also serving as a fuel, lowers the temperature required to ignite the mixture, this increases the rate of combustion. Of all the muzzleloader propellants available to users, black powder is the fastest igniting gunpowder of all.
Potassium nitrate is the most important ingredient in terms of both bulk and function because the combustion process releases oxygen from the potassium nitrate, promoting the rapid burning of the other ingredients. Proportions by weight are 75% potassium nitrate, 15% charcoal, and 10% sulfur.
Potassium nitrate, sulfur, and carbon react together to form nitrogen and carbon dioxide gases and these expanding gases provide the propelling action for bullets in rifles, more specific, muzzle-loaded rifles.
A great deal of smoke is produced when black powder is ignited. The smoke is generated by the charcoal and sulfur components of the black powder burning. Black powder produces a rotten egg smell as well when ignited, that is sulfur, which produces sulfurous acid or sulfuric acid which is highly corrosive to the muzzled-loaded rifles steel components.Safety:
To reduce the likelihood of accidental ignition by static electricity, the granules of modern black powder are typically coated with graphite, which prevents the build-up of electrostatic charge. Anyone handling black powder are well advised to wear cotton clothing as this reduces static electricity as well.
Granular size of black powder determines the intended use of the powder. The following sizes are for the specific use in muzzleloaders:
Fg: This grain size of black powder has the largest grains and normally is used in muzzle-loaded muskets and small cannons.
FFg: This grain size of black powder is smaller than Fg powder and is most commonly used in muzzle-loaded shotguns and larger bored rifles starting at about .45 caliber and up.
FFFg: FFFg: This grain size of black powder is smaller than FFg and is used primarily in pistols and muzzle-loaded small bore rifles .45 caliber and down.
FFFFg: This grain size of black powder is smaller than FFFg and is used only in flash pans on flintlock ignition systems.
United States Department of Transportation, have classified Gunpowder (black powder) as a Group A: Primary explosive substance for shipment because it ignites so easily.
Complete manufactured devices containing black powder are usually classified as Group D: Secondary detonating substance, or black powder, or article containing secondary detonating substance, such as firework, class D model rocket engine, etc., for shipment because they are harder to ignite than loose powder.
As explosives, they all fall into the category of Class 1.