I have a Bushmaster "Shorty" that I have run ~200 rounds of SA brass through. After firing it, I gave it a quick cleaning (ran the bore, oiled and stripped the bolt, and ran a light coating of CLP over the rifle and on the charging handle), but I left the chromed portion inside the chamber alone. Two weeks later, I took a look and there was carbon residue on it. I tried Hoppes, I tried Carb. Cleaner, Gun Scrubber, hell I even tried something made out of horse**** and the carbon won't leave! I've done the "pinky test" and no carbon residue comes off on my finger. Any ideas? I've tried a standard issue bore brush and no luck.
Jon
Jon