Storing gunpowder, even fairly large quantities, is not nearly as dangerous as we might think, because modern smokeless powders are not explosives, they’re flammable solids. When unconfined, they burn, generate little pressure, and leave quite a bit of sooty residue. When contained, for instance when inside a cartridge casing, which is surrounded and reinforced by a steel chamber, its performance changes completely; it generates a huge amount of gas pressure and burns much more completely, leaving little residue. Bottom line, gunpowder stored in the soft plastic canisters in which it’s invariably sold is quite safe to have around, granted we follow a few simple rules.
It’s worth mentioning, by the way, black powder is a completely different matter than modern smokeless powder, will explode even when uncontained, and carries with it significant safety concerns.
It goes without saying, I hope, we should store our modern smokeless gunpowder in an area predictably away from sparks, open flames, and any other source of extreme and potentially igniting heat. Uncontained smokeless powder will not explode, however it will burn at high temperatures, and can cause serious burns if it does.
Powder canisters are sealed at the factory. Leave the factory seals intact until you’re actually ready to start using that canister of powder. If buying multiple canisters of the same type of powder, always open only one canister and leave the others closed until use.
If possible, leave the powder in its original canister, which was designed to protect it from moisture and possible contamination, and is “soft” to serve as an uncontained environment, and avoid building-up pressure even if the powder should somehow ignite.
If the original canister is too large to be stored in a particular location and a quantity of powder must be transferred to a smaller container, always clearly mark the type of powder on the container. Unmarked powder of unknown type should be consider defective and disposed-of. It’s simply not worth the danger of guessing, “Well, this looks like…” and possibly putting together an unsafe load with the wrong powder, at a charge weight that would be safe were it actually the powder you think it is, but it isn’t.
Never store gunpowder is a hard container. Soft plastic Tupperware-type containers that mimic the “uncontained” properties of the factory canister are best. Actually, best is leaving the powder in the factory canister, if possible. That’s what it was designed-for.
Never store powder in a glass container. Light can penetrate the glass and create a greenhouse effect raising temperatures inside the container and degrading the powder over time. You’ve noticed your powder canisters are opaque? There’s a reason for that.
Store powder in a reasonably cool, dry location. Avoid storage in areas experiencing large temperature variations, for instance an unheated, uncooled outbuilding like a garage. Wide temperature variations can cause condensation inside even a sealed canister that will dampen and degrade the powder.
If you have a previously opened canister of powder you haven’t used for a long time, check it for signs of deterioration before using it again. In many powders, deterioration can be spotted as a red discoloration of the granules, and a red dust coating the interior of the canister. Powder in this condition is defective and must be disposed-of, as its burn characteristics are no longer predictable. It’s generally recommended you dispose of contaminated powder by burning it in a secluded location, such as a dirt pit, with the depth of unburned powder never more than an inch deep at a time.
How does the powder smell? Many powders have a strong alcohol smell from the solvents used during their manufacture. Lack of this smell can indicate powder degradation. However, if you don’t have a good sense of smell -and many people don’t – this is not a definitive test. Having said that, a strong acrid smell is a sure sign of deterioration. If it irritates your nose when you smell it, that powder is defective and should be scrapped.
Many people mark the date of purchase on the gunpowder canister, so they can ensure, if they have multiple canisters of the same type of powder, they use the oldest stock first.
By following a few simple rules, storing gunpowder safety even over the fairly long-term is easily accomplished.
