I wouldn't touch bore butter to my barrel as a preventative except to have an excuse to buy another muzzleloader... but that is just my OPINION of bore butter... hate the stuff.
I soak my barrels with LPS 3 and have NO PROBLEMS and clean it up with alcohol. In my caplocks I light off a heavy charge with it before going hunting to make sure everything is hunky and dory... even if don't in a hunting area.. I haven't found it to bother deer here in Hawaii.
Aloha...
