When I got started shooting, far too many years ago, used to go to the gravel-pit where the old fort used to be and shoot an 1860 Army Colt with the Anglican priest.
We had chain-fires, of course, made the world sound as if there were somebody loose with a full-auto blackpowder Colt.
ALL chainfires STOPPED when we started covering the rammed and loaded balls with nice, stiff axle-grease and making SURE that they were ALL covered. Likely it would work just as well with b'ar grease but you have to talk to the b'ar about that.
You can test this out for yourself if you like. Just load the gun and then grease FIVE chambers very carefully, then start shooting. If you get a chain-fire, it will be the chamber that you didn't grease. Then try it again with a single cap missing. It will not take long at all for you to become convinced, as were both Armies in the War for Southern Independence, that the cause of chain-fires is chamber-flash communicating to adjacent chambers.
And please believe me whan I say that you definitely do not want FOUR going off at the same time.
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