As most of you know our original gun powder was called black powder and was a mixture (mechanical) of sulfur, charcoal, and nitrate usually in the form of salt peter. this was only marginally successful and very tricky to mix without exploding. It is historically recorded that China invented gun powder however if you read about the travels of merchants in this ancient time period you will find gunpowder being sold to the Chinese. Somewhere along the line someone tried to mix the three ingrediants with some liquid to keep them from exploding and surprisingly it worked and also made a superior powder. In practice the ingrediants are mixed in a paste and spread in a flat container. After drying they are broken up in small pieces. This is called corning. and a small, all brass machine does the grinding up of the cornned powder. It then is run through various screens each one coarser than the first and the powder particles that drop out are graded by the screen that they will pass through. The screens are called "fines". So the fines count backward with 4 Fine being the finest and 1 Fine the coarsest. 1 F was the big chunks and used in cannons. 2 F in large guns 3 F in pistols and small caliber rifles and 4 F used as priming for flint locks. There was actually a 5 F but it was so instable that it was thrown back into the pot as was the larger chunks that would not go through the 1 F screen and recorned. The 5 F was sometimes used to manufacture fireworks. The black powder era lasted for over 600 years but its limitations soon had chemists working to replace it. One reason was, you had to have a large bore to use black powder so you could get off more than a few shots without having to clean out the accumulated crud. Large bullets did not go as far or as fast as small bullets. It took the development of organic chemistery to give the means to achieve the goal of a clean gun powder. The side effect was also less smoke which endeared it to the soldier hiding in the woods.
The first breakthrough in explosives was done independently by a couple of European professors in 1845 and 1846. It was discovered by them that the action of concentrated nitric acid on natural cellulose fibers ( usually common cotton) was to rearrange the atoms and add oxygen and nitrogen molecules to the cellulose. Called nitration. On ignition the cellulose nitrates separate explosively into carbon monoxide,
dioxide, hydrogen, nitrogen and steam. These gases expand to a much greater volume than the solid nitrocellulose. And the action releases considerable heat which further increases the volume of gases. Unfortunately the reaction was uncontrollable and unpredictable so for a while nitrocellulose (also called pyrocellulose, gun cotton) was only used in explosives. About 1870, celluloid was invented. It was an early plastic and was a break through in controlling the burning rate of nitrocellulose. That is something isn't it. First came plastic and then came gunpowder. Now you can say paper, plastic or gunpowder and be correct. Of course the clerk at the check out will not have the foggiest idea what you are talking about. It took 14 years later before the French chemist Vieille, applied this discovery to manuracturing smokeless powder. This propelled France to the top of the military heap. And had the other countries scambling to catch up. He found that nitrated cellulose fibers could be colloided into a gelatinous substance with a mixture of alcohol and ether (don't try this at home laddies) It then was rolled into thin sheets (does this sound familiar "corning") cut into flakes and then the solvents evaporated. The dried flakes were strong, elastic and most important burned only on the surface at a much slower rate than the untreated material. This was the final basic development that made modern smokeless propellents possible.
Later discoveries that the buring rate could be controlled by the granule shape and by the addition of additives and coatings that functioned as a sort of temporary fire proofing of the powder granule and further slowed its burning rate. One unexpected benefit from the deterrents was that they reduced the flame temperature of the burning powder and thereby reduced barrel erosion and gave longer barrel life.
There is more to the gunpowder story as the saga is not over yet. The invention of double base powders and substitute black powders are chapters in themselves. I have always been interested in guns and to learn their history and beyond is a added pleasure and appreciation of their uniqueness. Hope you enjoyed this history lesson.
All smokeless powders obviously have to burn very fast, but handgun and shotgun powders must burn faster than fifle powders. You will readily note the fidderences in physical size and shape of various powders, but you cannot see fifferences in chemical composition that help to control the rate of burning. Burn rate is also affected by the pressure. "HOT PRIMERS", seating the bullet too deep, overcrimping, oversize bullets, use of heavy shot loads and anything that increases friction or confinement of the powder will increase the pressure. This hobby REQUIRES attention to detail, patience, and meticulousness to ensure the satefy and quality of the loads produced.
1. Don't mix powders of different kinds.
2. Store powder in a cool dry place.
3. If you throw or measure powder charges by volume, check-weigh the charges EVERY time you begin loading.
4. Pour out only enough powder for the immediate work.
5. Don't substitute smokeless powder for black powder or Pyrodex.
6. Don't carry powder in your clothing. Wash your hands thoroughly after handloading.
7. Store powder in the original package. Don't repackage.
8. Keep powder containers tightly closed when not in use.
9. Specific powders are designed for specific uses. Don't use them for other purposes.
10. Empty the powder measure back into the original powder container when through with a reloading session. DO NOT MIX POWDERS.
11. Obtain a copy of SAAMI( Sporting Arms & Ammunition Manufacturers Institute, Inc.)
ADDRESS: National Reloading Manufacturers Association
4905 S.W. Griffith Drive, Suite 101
Beaverton, Oregon 97005