Home Forums Hunting & Shooting Muzzleloaders A bad cleaning habit finally exposes itself

I sold a gun to a guy I know, it had been shot a decent amount but always cleaned well. To the naked eye (and on the patches) it was spotless. He used JB to "take it down to super clean" he said. Once he ran the JB in it, it appeared dirty - the plastic fouling showed up. So it may be possible that is what you are dealing with. This was an older gun, so no packing grease, etc. I have never used JB like that, so I can't comment from personal experience.