I just spray brake clean or carb clean on it, wipe it down with a rag and lube it up. If its really bad, I soak it in hoppes 9 completely disassembled for a couple hours and brush with a brass brush, dry it then lube. I normally at least do my carb clean spraydown of the bcg after every shooting. Barrel gets left alone, 2k now barrel untouched, still holds a group.