I wouldnt use brasso, it has a mild abrasive. Try Nevr Dull. Comes in a blue can. It's an impregnated wadding used to polish brass, copper, etc. mild. Also, back when, we would center-cut out a piece of round stock alum at teh end, slip a piece of nevr dull in the slots, hook it in to a cordless drill and polish out our barrels. let it dry to a haze and then use those light blue paper towels (auto section at walmart) to polish it clean. Like Butta!!