Granulation

Granulation: Black powder is produced in different sizes or granulations as indicated by the number of F’s on the container’s label, with Fg being the coarsest and FFFFg being the finest. The size of black powder you use depends on your firearm and the manufacturer’s recommendations.

Fg

Coarse grain typically used in cannons, muskets, rifles larger than .75 caliber, and shotguns that are 10-gauge or larger.

FFg

Medium grain typically used in larger rifles between .50 and .75 caliber, 20-gauge to 12-gauge shotguns, and pistols larger than .50 caliber.

FFFg

Fine grain typically used in smaller rifles and pistols under .50 caliber and smaller shotguns.

FFFFg

Extra-fine grain used as a priming powder in the pans of flintlocks. Never use FFFFg black powder as the primary powder charge in a rifle, pistol, or shotgun.