Hey guys, I am new to NES. I was just wondering if anyone had any suggestions on a reloading media to help me with some really dirty brass. I have a PTR 91 and becuase of the flutes in the chamber, the outside of the brass gets really really dirty from blowback. The regular walnut media with polish from RCBS that I use for everything else just doesnt do the trick. Any help would be appreciated, thanks.