As the large, water-driven wheels rotated around the table, their great weight incorporated the ingredients for gunpowder in one-fourth of the time needed by stamping mills. Image courtesy of Hagley Museum and Library

Smokeless propellants have considerably more energy content than blackpowder. As they burn, smokeless propellants release energy in the form of hot, expanding gases that are comprised of carbon monoxide, carbon dioxide, nitrogen, hydrogen, and water (steam). Unlike blackpowder, smokeless propellants convert nearly all of their solids into gas and leave little residue. The shape of smokeless propellant grains is a major factor in producing a progressive burning rate.

How Blackpowder Is Made
Manufacture of blackpowder is a seven part process:

I. Incorporation
The three ingredients and a small amount of distilled water are placed under an incorporation wheel. As this large stone or iron wheel rotates, it crushes the moist ingredients together under tons of pressure. The result is called "millcake."

II. Pressing
The moist millcake is placed in a press that reduces its volume by about half. The result is called a "presscake."

III. Drying
The still-moist presscake is allowed to dry thoroughly.

IV. Graining
The dry presscake is broken up into small, irregular grains.

V. Sorting
The grains are sorted according to size in a sieve stack.

VI. Coating
The powder grains are rumbled in rotating wooden barrels with graphite powder.

VII. Packing
The finished blackpowder is placed into containers by weight.

Manufacturing Improvements Around 1400, the first stamping mills were developed to replace hand incorporation. A stamping mill consisted of a series of mortars and pestles operated by hand power. The three, dry ingredients were placed in each mortar and then worked and crushed by the pestle for 24 hours. This was difficult, dangerous work, and accidental explosions were common. The result was a dry powder called "serpentine." These stamping mills were replaced about four centuries later by roller-wheel-mill incorporation, which was safer, faster, and cheaper.

By about 1500, a second improvement in blackpowder manufacture called "corning" was developed. In an effort to reduce the number of accidental explosions during incorporation, gunners began adding a small amount of moisture to the blackpowder to reduce dust and friction. The resulting moist paste was formed into large loaves called "dumplings" for transportation. At the gun site, the dumplings were crushed into small pieces by hand. The corning process mixed the ingredients much more closely, and it was quickly found that not only was corned blackpowder more reliable than serpentine, it was much more powerful. Gunners quickly appreciated that the space between the powder grains was the cause of this, so they started deliberately making blackpowder into grains by forcing the moist paste through screens, then sorting the dried grains in sieves.