I get the idea of the wax to seal the nipple as per described when one is going to load the revolver to be carried for perhaps days in unknown weather to prevent inclement weather from rendering the cap inert. Sounds reasonable back in the day when C&B revolvers were the only option. I don’t know anyone doing do today, when we load and shoot, not load and carry. While chain fire can be an issue, if the ball is properly sized, it should fit tight enough to leave a small ring of lead shaved off by the mount of the chamber. Even still, chain fires have been reported. I personally don’t believe that a cylinder loaded thusly can chain fire but claim it to be so. Most that I know put some sort of grease over the ball for insurance but, in my experience that has not a great solution as after the first shot all the grease melts out of the subsiquent cylinders and just makes a mess. I seriously doubt that chain fire would be if any concern with the shotgun in question. In order to have a chain fire, a spark would have to breech the entire shot column including over powder and over shot wads, not just a few thousandths of lead ball that is touching the cylinder set walls. That being said, jump flash(the flash made from the sparks and hot gases escaping when the charge jumps from the cylinder to the barrel) would be concerning in a rifle format but don’t see how this would be any different that the Colt revolving rifle.
