Name: 6:3:1
| percent | parts | component |
|---|---|---|
| 60.00% | 6 | Potassium Nitrate |
| 30.00% | 3 | Charcoal (airfloat) |
| 10.00% | 1 | Sulfur |
Chemicals are pre-ground very fine, then screened together well. May be milled into meal which is slower than conventional 15:3:2 black powder meal.
This is a very common rocket propellant composition. Almost all traditional black powder core-burners use a small variation of the 6:3:1 ratios. Adding up to an extra part of Potassium Nitrate is useful for small rockets that are a bit sluggish at take off. Ball milling is generally necessary for 2 oz or smaller rockets for the best performance. Wet granulation is helpful for simplifying loading.
Larger rockets use more coarse charcoal and/or no milling. A good starting point is:
2 oz 3 parts airfloat
4 oz 2.5 parts airfloat, 0.5 parts -60 mesh
8 oz 2 parts airfloat, 1 part -60 mesh
1 lb 1.5 parts airfloat, 1.5 parts -60 mesh
2 lb 1 part airfloat, 2 parts -60 mesh
4 lb 0.5 parts airfloat, 2.5 parts -60 mesh
6 lb 0.5 parts airfloat, 1.5 parts -60 mesh, 1 part -20 mesh
The milled meal works well in cracker fuse, 6:2:1 may be better, especially with moist construction which tends wick out the nitre into the paper.