By John Kleespies
After emptying a dispenser of gunpowder, you may notice a film of gray dust left behind and assume that it is residual gunpowder. In fact, you are probably looking at graphite.
During the manufacture process of modern gunpowder, graphite is tumbled with the powder, thus coating the individual flakes in a protective layer of insulation. This process is known as “glazing,” and it has actually been a common practice since the mid-1800s.
Glazing has two (or three) primary benefits….
First, the graphite coating offers some mild protection against water absorption. Think humidity-level resistance, not left-out-in-a-rainstorm proofing. This helps the gunpowder to remain stable if you forget to put the cap back on your cannister for a few days, but that’s about it.
The second and third(ish) benefit is that the graphite dramatically cuts down on static electricity buildup in the powder. Remember being a kid and rubbing a balloon on your hair and then sticking it to the ceiling? When gunpowder does its version of this party trick, it clumps. By reducing static electricity in the powder – not to mention the inherent lubricity of graphite itself – the powder is encouraged to stay separated into individual grains, which assists with consistent metering.
The third(ish) benefit to glazing also has to do with static electricity: namely, the graphite should prevent static from building enough to create a spark, which could potentially result in an unintended detonation.
Worthy of note is that gunpowder containers are now made of plastic rather than metal, as they were many decades ago. This is to further reduce the chances of a static electric spark forming during storage and transportation.
