Originally Posted by
Bert2368
A couple of observations from someone who has mixed up several types of things that go "bang", even got a license to manufacture.
Your ingredients quality is very important. If you can access it, get Potassium chlorate sold to MATCH MAKING COMPANIES. This product will be very good, pure chlorate as matches need to be storage stable for years, even decades. The best stuff used to be made in Spain, look very carefully at the spec sheets for any Chinese chlorate and just don't trust home made electrolytic chlorate for any storage life unless you know enough chemistry to do your own purification and TESTING after.
Similarly, "Sulfur" covers a wide range of commercial products. If you can find "rubber makers Sulfur" which is a grade extracted from sour crude oil during refining, this is very pure and suitable. It will not hurt to wash even this variety in several changes of warm water anyhow, in case any oxidation has occurred in storage and started to produce sulfurous acids- Chlorate and ANY acidity are a bad mix, resulting in either slow deactivation of the mixture or a fire.
If you are damping a mixture with water, use only DISTILLED WATER. Well water is a bad choice for chemistry and a particularly bad for explosives chemistry. Example: Some while back, GOEX had a problem with their factory water supply and fell back on using untreated well water from a well on the plant property for damping powder while milling until things got fixed. Shortly after, the US military noticed a number of problems with weapons systems using black powder for igniters, bursters and so on becoming erratic or failing to work at all- Which was traced back to the hard well water used in those lots of powder. Primers are WAY more sensitive to contamination problems of this type than black powder...
If you use nitrocellulose lacquer for binding/waterproofing, be aware that it comes in a wide variety of nitration %, degree and type of storage stabilization and viscosity per weight of solvent used. For commercial nitrocellulose lacquers, hydrolyzed "microcrystaline cellulose" may be used for the nitration which comes in a number of different lengths of cellulose molecule, chosen for the desired viscosity of the lacquer being produced. Dissolving single based powder by first soaking them in ethanol & then adding acetone works... But don't expect different source materials to behave the same, you will have to start over experimenting if you change ingredient sources.
Similarly, cheap solvents from the hardware or paint store are not very pure- Take the time to find more expensive but purer reagent grade solvents and/or consumption grade 180 proof ethanol, you're not using very much.
About sensitizing with grit: As someone above noted, fine "soda glass" powder melts at the temperature of a primer flame. Quartz sand DOES NOT. Asside from sand possibly causing barrel abrasion, MOLTEN DROPLETS OF GLASS STICK TO POWDER GRANULES AND TRANSFER HEAT THIS WAY, CAUSING DURABLE HOT SPOTS. It's not just included for the sensitizing to friction & shock. I make a high temperature prime for pyrotechnics which includes DIATOMACEOUS EARTH for this reason, the microscopic skeletons of diatoms melt in the flame and stick to what I'm trying to light, even though it is moving through the air at high speeds. You might try a bit of this, it's dirt cheap.
Keep quantities small and keep your fingers where they belong.