Things You'll Need
Instructions
Remove as much of the existing bluing and rust as possible; follow the manufacturer's instructions. Use steel wool or fine-grit sandpaper to limit any remaining rust.
Put on rubber gloves; wipe off the oil residue with clean cotton-balls.
Heat the gun or metal object in a warm oven. The heat opens the pores of the metal, resulting in better bluing. On a hot, sunny day, the gun might be warmed in the sun instead of the oven.
Apply bluing to the area with a cotton swab. Apply the solution evenly in one pass. Apply the bluing in small areas or in minor scratches with toothpicks. Wipe the area with steel wool -- after applying the bluing -- to even out the area.
Apply the bluing -- and use the steel wool -- several times. Continue until the desired look is achieved. Several coats are usually required to obtain a dark-dull or black finish.
Sand the area with fine sandpaper. Limit the sanding to the treated area. Apply gun oil to the area, and allow it to sit for 12 hours. Wipe off the oil with cotton balls, and then reapply. The process of applying the oil, waiting and wiping is typically repeated at least three times.