Black powder is used for the manufacture of ejection charges in fragmentation (bounding) and signal mines, as well as for the manufacture of safety fuses and igniters for rocket charges. It is a mechanical mixture of potassium nitrate (75%), charcoal (15%), and sulfur (10%). Depending on grain size, the powder is divided into fine-grained and coarse-grained types.
Black powder is highly hygroscopic; under the influence of moisture it becomes damp, and at a moisture content above 2% it becomes unsuitable for use. Powder that has been dried after becoming damp has reduced properties.
