I agree with Bill Schodlatz. But if it really looks bad and you are determined to use a cold blue to spruce it up a bit, there is none better and more durable than Brownell's Oxpho Blue. A bit of practice with it on a junk barrel wouldn't hurt because the final appearance has a lot to do with technique. Always pour a little into a small container and use that for your applicator pads. I find that using a small wad of 0000 steel wool as an applicator and rubbing it into the steel helps to get a nice even finish. Never contaminate your bottle with a used applicator pad, or return any used solution back into the bottle.
