When I prepare mine for hunting I wipe the bore as dry as possible then pour alcohol down the barrel and let it run out the nipple. Hard to be assured you've gotten it all out of the drum and nipple if you don't. Of course, not an issue with sparkguns. I still don't understand why moisture was attracted to the chamber area of my rifle if the bp had nothing to do with it. Guess I'll never know.

May God bless America and those who defend her.