Oil and Steel Wool
If you spray the barrel down with Rem Oil, or WD40, and rub the barrel with steel wool pretty hard, it will come off. Don't worry, if the metal is blued it isn't going to hurt it. Trust me it worked on my guns. Good luck!
Criminals obey gun laws in the same way politicians follow their oaths to office - Anonymous
It's better to be silent and called a fool, than to speak and remove all doubt