I just re-blued my old Renegade barrel. I used Birchwood Casey Cold Blue and it worked pretty good. I had built the rifle from a kit back in the late 70's or maybe very early 80's and the brown that was on it just wore off. I kind of like the barrel again. Then I put a new set of T/C sights on it, so I might have to take that to the range and see how it does.