A friend had a very bad accident at his shooting range this past weekend. First off, he is a very careful man in all of his shooting pursuits, seriously, but sometimes it's the little things that are our (his) undoing.
While shooting a new-to-him .54 Hawken percussion gun, a can of blackpowder exploded at less than arms length. A spark from the gun ignited the powder. It was standing open on the bench because he was charging his powder measure directly from the can for each shot, his protocol being to close the can after each charging. He dropped the can lid on the ground, but went ahead and fired the freshly prepped charge before bending down to retrieve it, leaving the container stand open. "I'll pick it up after this shot."
How can a percussion gun dispense such sparkage so as to cause the explosion?
Evidently, upon thorough investigation after the fact the gun was found to have its hammer at full cock. Hmmm, that shouldn't be, it should've been down in the fired position resting on the spent cap. Upon removing the nipple for cleaning the why-for became obvious - its vent hole had been reamed out to a very large diameter by a previous owner. The resultant magnified venting allowed an excessive amount of back-blast to channel back out into the atmosphere, throwing lots of hot flotsam and jetsam out and causing the hammer to fly back into full cock. One tiny bit of something, or a spark, made a perfect dive into the powder can. Boom.
It blew his shooting box 20 feet away, and scattered everything else to hell-and-gone. He himself is a very very very lucky man - he sustained 1st&2nd degree, and some 3rd degree, burns over his head and upper body. All hair - poof, gone. Clothes on fire. Scary (but good) part was his shooting glasses looked like they were raked through the coals of a campfire and then shot with a shotgun - but his eyes were A-ok. Luckily there was somebody with him who got him squared away and a trip to the ER got him fixed up (kind of). He's home and on the mend, but really rattled as you might imagine. (The gun is perfectly ok.)
Moral of the story: don't drill out the hole in a percussion rifle nipple, even if you think it might aid ignition for some reason; and don't ever leave containers of gunpowder stand open on the shooting bench. If you're having ignition issues, resolve them by other means.
