http://members.aol.com/illinewek/faqs/bptypes.htmBlack Powder Types and Grain Sizes
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The primary difference between "FA" and "Fg" type powders is processing. Both powders begin as milled "meal" powder. The potassium nitrate, charcoal and sulfur are milled together into an extremely fine powder. This milling process takes many hours and is done by remotely operated equipment due to the inherent danger of the process. The meal powder is consolidated under high pressure into a "mill cake" or "press cake" of solid Black Powder. Powerful hydraulic presses are typically used to press the meal powder into solid cakes. The mill cake is then dried and crushed into grains. The crushing process is called corning. Both types of powder are screened to remove fines and to separate the different grain sizes.
Blasting "A" type powders are not usually tumbled. If blasting powder is tumbled, it is just for a short time to knock off any sharp and long projections. Sporting "g" type powders are tumbled with a tiny amount of graphite to polish the grains. The Black Powder formula is the same. The graphite is not part of the basic Black Powder formula. Graphite does act as a burn rate modifier. The trace of graphite slows the burn rate slightly. Grain sizes are different for sporting and blasting powders.
The "A" type powder is a blasting powder, and is used mostly by pyrotechnicians and for some specialized quarry work.
Sporting Grade Black Powder
Whaling 32/64" mesh 3% held 4 mesh 12% pass |
Life Saving 6 mesh 3% held 12 mesh 12% pass |
Cannon 6 mesh 3% held 12 mesh 12% pass |
Saluting 10 mesh 3% held 20 mesh 12% pass |
Fg 12 mesh 3% held 16 mesh 12% pass |
FFg 16 mesh 3% held 30 mesh 12% pass |
FFFg 20 mesh 3% held 50 mesh 12% pass |
FFFFg 40 mesh 3% held 100 mesh 12% pass |
FFFFFg No Longer Manufactured by Goex |