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You guys either know of or have seen his name - Ron Long (Long's Lock). Ron is a super person willing to help anyone along with being a super shot with either modern or traditional firearms. He probably shoots more than anyone alive or close to it. So he knows what he's doing around guns and black powder.
He told me he was tuning one of his flintlocks, walking around the shop with the lock out of the rifle snapping it to check the amount of sparks going into the pan. He made the mistake not even thinking about it and tested the lock's sparks over his shooting box.
The sparks went into the open box hit the film of years of black powder build up and went bang with the help of a full flask of powder. Ron got third degree burns on his face and arms/hands, the explosion took the overhead door off its rails and knocked items off the walls.
So even someone with years of experience being around explosives can make a mistake.
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