What you will need:

  • abrasive paper (preferably cloth backed) 120-400 grit

Remove pitting with files and or abrasive paper. Your metal preparation will probably begin with a coarse grit abrasive paper, but should be completed by using 320 or 400 grit.


 What you will need:

  • detergent (Simple Green)
  • scrub brush
  • tongs or wire hooks
  • air compressor or paper towels
  • clean cotton gloves

Degreasing is essential in getting fine results. Parts should be soaked in hot soapy water   using a cleaner such as Simple Green. Scrub parts with a brush during the cleaning process. Remove parts from the cleaning solution with tongs or hooks. Rinse thoroughly with hot water, and dry with compressed air or blot with paper towels. Do not touch cleaned parts with bare hands as the oils from your body can contaminate the metal. Wear clean cotton gloves while handling degreased metal parts.

 ETCHING (Optional)

 What you will need:

  • sandblasting gun
  • 150 grit garnet (aluminum oxide can be used)

Etching helps the first applications to take hold of the base metal. Etching can be accomplished chemically (acid dip) or mechanically (blasting with media). I do not recommend using acid because it is too hard to control. Blasting with 150 grit garnet is the best. The polished metal will appear dull grey after blasting but the process of rust bluing will bring the sheen back. The finish will look almost the same whether it is blasted or not. The blasting is best to do after the degreasing and parts should only be handled with clean cotton gloves.

Warning:  Do not blast with glass beads as the beads produce different textures to hard and soft steel.


What you will need:

  • vinyl or latex gloves
  • cotton gloves
  • natural sea sponge, cellulose sponge, cotton swabs, or poly foam paint brush
  • small glass or plastic container
  • propane torch or other heat source
  • steel wire brush (.003-.005) or oil-free steel wool
  • container for boiling distilled or deionized water (tap water can be used in many parts of the country but it depends on the mineral content in your area)

Pour solution into small glass or plastic container. Warm metal parts to 150-200 F with a propane torch or other heat source. Use vinyl or latex gloves during application. Dip applicator in solution and apply to warmed metal parts. If the solution does not evaporate right away run the flame back over the metal parts to dry the coating. A coating of brown to yellow rust will immediately form.

Coat two more times drying the coating with the flame each time. Submerge part in boiling water for 2 minutes, remove from water and dry with compressed air or paper towels. The boiling water converts the red rust to black rust. Using clean cotton gloves remove powdery residue with steel wool or a fine wire brush. The coating is very tough so do not be afraid of carding it too hard. The metal should now be silver grey, black and mottled.

Look closely and if you see any red or brown colored areas card these areas until they are silver grey. Do not worry about the uneven finish, as it will even out with each application.

Warm the metal parts again and coat with solution three times. Boil in water again to convert the red rust to black. Remove from water, dry, card and repeat process 6-10 times. When satisfied with the metal finish, oil parts and coat the bluing with RIG (gun grease) and leave set for 24 hours.


What you will need:

  • baking soda

This step can eliminated if fresh water is used to boil the last few coats. Soak blued parts in a solution baking soda and water at room temperature for 5 minutes, rinse and oil.


During the whole bluing operation don’t touch the metal with your bare hands as you can leave contamination spots in the finish.

After the first boiling and carding examine the metal under the light of a regular light bulb or sunlight. If you see any shade of brown or purple card the metal until the metal is silver, grey, or black. Applying coats over the top of bad color will lock it in. You usually won’t see it happen again after the first boiling and carding.

If you have a very small spot along a rib that doesn’t want to take color, take a piece of new 400 grit paper and scuff the small area. The next coats should take.

If you use steel wool for carding make sure to buy oil free steel wool. It is available at fine wood working stores. If you must use regular steel wool soak in acetone to remove oil.

Heat a practice piece of steel swabbing on solution with a poly foam paint brush 5 or more coats reheating when necessary. Boil, card, and repeat. Coat the part like you are trying to ruin it. I think you’ll be surprised with the results.

Garnet is preferred for etching (blasting) as it is unlikely to imbed in the metal. This is only a concern on parts that rub against each other such as the bolt.

Do not try to blue the ends of a barrel because you don’t want to get any bluing solution in the bore. Polish the barrel crown back to white after bluing. I don’t plug bores anymore but I make sure I’m using fresh water when doing barrels.

I have found that I can usually repair rust blue finishes without stripping the part. Polish only the problem area. Coat the repaired section and when the color matches recoat the whole part with one or two coats.

Using the rust blue to touch up damaged screw heads is easy and the bluing won’t rub off.

If you don’t have a boiling tank and are only going to do a few guns you can buy a piece of PVC pipe, glue a cap on one end, hang your barrel in the pipe and fill the pipe with boiling water each cycle.

Parts can be strung on a wire for boiling but don’t wire brush the parts with the wire attached. I almost lost an eye when the wire brush grabbed the string of parts.

After initial cleaning, a light scrub down with a 3M Scotchbrite pad while in the water rinse is often helpful to insure that all cleaner residue is removed.

Sometimes carding with steel wool and water can blend a streak in the blued finish. Some finishers prefer to use water and steel wool in all carding operations.

Rust bluing can be lightly buffed with a loose muslin wheel and a compound used for mirror finishing. This adds a little sheen to the finish. This operation can be done just before applying grease or oil to the finished parts.