Was at the range last year. Guy had a black powder revolver. He fired one shot and it caught fire. He dropped it and ran, the piece continued popping off rounds in all directions. We all jumped behind something or hit the ground. In the end we had a good laugh, but it wasn’t so funny when the rounds were cooking off. He promised to clean it, put it in a case and place it over the mantle. I hope it is still there! I’ve had my OK Corral moment, one is all ‘ya need!
I’ve shot black powder pistols for years and never had an issue. My dad had a chainfire when he first used his Colt, and he learned why sealing the cylinder was so important. Operator error is not the fault of the weapon.