View Full Version : Bluing and re-bluing questions - process/products - suggestions?

September 3, 2010, 03:21 PM
I'm not sure if this is the right forum to post this but it does sort of go with "gunsmithing" so I apologize if it should be posted elsewhere.

Question -

I am looking at a Colt Official Police - 38 sp with 5 inch barrel. It is in great shape as far as mechanics but it does show overall wear on the bluing. There is no "pitting" etc. and bore and chambers are excellent. The price is fair on it and I probably will pick it up. I didn't get the serial # but I believe it was probably made in the late 20s to mid 30s. If I get it, it will be a "shooter" not a "collector" and I would want to fix it up with new grips and re-blue it. My question is this. Can some of you give me your recommendations on bluing products on the market that would give good results and a nice deep blue finish? I'm fairly skilled at handwork and removing the original blue and doing the polishing, etc. to get the revolver ready to be reblued isnt a problem. I realize the final results won't be the same but I really don't want to spend the money for a professional hot blue job (probably $200?) but I do want to use a product that I can apply in my shop that will give good results and be fairly longlasting. Years ago I used a number of "cold blue" and "paste blue" products but I really wasn't satisfied with the final results. That was 40 + years ago and I'm sure that there have been improvements made in the products available today. Any tips, suggestions, sources, etc. would be greatly appreciated. Many thanks! sincerely, bedbugbilly :)

September 3, 2010, 05:21 PM
That's the problem, bluing is a very simple process, and gunmakers had it figured out by the turn of the last century. So the cold blue you tried 40 years ago is the same as you buy today. There are modern coatings out there, but nothing says "blue" like a professional job.

September 3, 2010, 06:35 PM
No bluing job will ever look as good as a proffesional "hot blue" job, but a GOOD job is not cheap. As an alternative, Brownell makes an excellent "cold blue" product called Oxpho-Blue. I have found through experience that you can obtain a pretty good finish using this product. The trick is getting the gun ABSOLUTELY greaseless. The better job you do of degreasing, the better job you'll end up with. Just follow the instructions and no shortcuts.

September 3, 2010, 07:28 PM
Thank you for your input and advice! It's greatly appreciated! I know that there really isn't anything that is a substitute for a "pro job". I had read about the product from Brownells that was suggested but I couldn't remember the name of it. I do remember that he fellow had pretty good luck with it and he had used it on a cap and ball revolver. When I was studying metalworking in college many years ago, we used some type of solution of small things that we made (jigs, etc.) that gave them a dark black type of what I would call "bluing". Unfortunately, that is a lot of years ago and I don't remember what it was. I do remember that it was fairly simple to apply and it gave a deep, black finish similar to bluing that was quite durable. I suppose the original bluing could be touched up where it is worn but I have to question how well the touch up would blend in with the original Colt bluing and if it would stick out like a sore thumb? I have used "Plum Brown" on barrels, locks, etc. of muzzleloaders that I've built and have had great success with that in getting a nice deep browned finish. I've even given some thought to removing the bluing and "browning" it if I get it. It certainly would be "different" than the norm but I think it would be attractive with some faux ivory grips on it. At any rate . . . thanks to you all for the information. Now I have to "get it bought" and go from there!

September 3, 2010, 11:20 PM
I've seen instances where Birchwood Casey's Cold Blue looked like a light pro job when heat was applied prior to the application with a hair dryer. The key is to get it hot to the touch with the hair dryer, and THEN apply the cold blue. It takes 3 or 4 coats, but it does a good job.

Then there is Perma-Fin by Birchwood Casey. It you want a satin black finish instead of a bake on or pro-blue job ... this is a good alternative. When I get back home on Tuesday I can post a pic of a Perma-Fin job. It looks a lot like the old 'Black' blue on older revolvers (70's & 80's era).

Major Beef
September 8, 2010, 06:06 PM
I just used Birchwood Casey's Permablue on my S&W 5904. First time I've done anything like this. There is some minor blotchiness, but overall looks pretty decent. Definitely turned out better than I expected. But then I was expecting it to turn out like poop since it was my first attempt at cold bluing.

Bill DeShivs
September 8, 2010, 08:30 PM
If you manage to get a good finish with cold blue, it will wear right off. Cold blue is not durable.

James K
September 8, 2010, 09:33 PM
+1, Bill. I have read about dozens of magic cold blues, and tried a number of them. They just plain are not durable. Some makers advertise them as "used by gunsmiths", which is true but they don't say that gunsmiths use them only to touch up a screw head or darken a front sight, not for a full reblue job.

The only blue that can be done at home that will be durable is rust blue, like was used on many guns prior to the middle 1930's.* It is tedious, and it is best to practice on some scrap, but rust blue will give good results. However it is not suitable for a touch up job, nor is tank blue. The gun has to be taken down to bare metal.

Today, many gun owners use a paint of one form or another; they give good results but never (IMHO) equal the quality of a professional blue job.

Now, my advice is that unless that gun is really bad, with only a little blue left, don't do anything. If it has 60-70% or more, leave it alone.

*WWI era Lugers and Mauser rifles are good examples of rust bluing.


September 8, 2010, 10:35 PM
If you manage to get a good finish with cold blue, it will wear right off. Cold blue is not durable.

I must disagree.

I applied a cold blue finish to an old sporterized 1903 Springfield that has lasted over 20 years.

Here's how I did it:

First, disassemble the gun completely. There are a number of good references, but the best (IMHO) are the shop manuals from Jerry Kuhnhausen.

You then have to remove the old bluing. Birchwood Casey's Rust and Blue Remover is a good way to do it. Follow the instructions on the bottle exactly for best results.

The best bluing job is only as good as your polishing. For a high gloss finish, I usually start out with 400 grit on loose muslin wheels, followed by the 555 series polishes all the way through 555 White. Take care not to round off any corners or polish out the lettering. Slow and easy is the trick--very little pressure is needed, and let the wheel do the work for you. Polish with alternate angles--do the first passes in one direction, then turn the work 45 degrees and do it again.

When you have polished to your satisfaction, you are ready to blue. Clean the outer surfaces again, this time with alcohol--and DON'T TOUCH THE OUTER SURFACES AFTER CLEANING. This will leave fingerprints on the work.

You can heat in two ways. One is a low flame, and a few short passes; the one I prefer is to completely immerse the piece in boiling water for about a minute. Make sure the work does NOT come in contact with the bottom or sides of the pan.

Get the tube of Birchwood Casey's paste, and some applicator swabs. After you take the work out of the boiling water, it will dry almost immediately. Apply the blue onto the hot metal with overlapping strokes. Don't be stingy with the stuff, either.

Wait about one minute, then rub the blue off vigourously with a bunched up brown paper bag.

Apply another coat of blue; rub off again, and this time polish the piece with another folded up bag.

You can also use these instructions for Brownell's Oxpho-Blue--but to get it off and even the coats, you will want a fine carding wheel, also available from Brownells.

If you do it right, you will be amazed at the depth of the finish you can achieve. But, you aren't done yet!!!

Coat the piece liberally with WD-40--this water displacing oil will get any residual moisture from the metal. Let the work cure for at LEAST three full days before handling it. I have done firearms with this method--when done properly with a nice master-grade polish, the gun will look like black glass. Good luck with your project!

PS: Something to consider--by the time you assemble the proper tools for the job, you will probably come out ahead to do the polishing first, drench it in WD40, and send it to a gunsmith who can do a hot tank blue on it.

Bill DeShivs
September 9, 2010, 01:58 AM
Been there, and done that.
Most cold blues are simply copper sulphate. They simply don't hold up well.

Major Beef
September 9, 2010, 03:05 AM
I'm curious as to how the bluing would come off on a cold blue job. If it's just a range gun with no holster time, will the bluing still come off on its own?

September 9, 2010, 07:43 AM
Ive tried the cold blueing on several guns ive owned in the past they all wore at the edges real bad just from rubbing with oil from standard care. I have a 1911 in 9mm slide still looks pretty good but the frame is wore bad Im thinking of sending her back to colt and let them blue her . I think they do some pretty blue work. dark deep and nice

September 9, 2010, 02:13 PM
Here's one trick that I have tried for small parts (so far; I have no reason to think that it wouldn't work for an entire gun, if done properly):

Brownell's Oxpho Blue is really a superior cold blue. Remember that bluing is actually rust--it's just controlled oxidation, done in such a way as to uniformly darken the steel.

You would have to get enough of the stuff to completely cover the part. I would also use corks to plug the bore, since no heat other than gentle warming is involved.

Completely clean, degrease and polish. Small tanks that are suitable for holding the Oxpho-Blue are all available from Brownell's.

After the prep I described above, completely--and I mean COMPLETELY--immerse the part in Oxpho-Blue. Let it marinate there for about 5 minutes.

When the part is removed, it will look HORRIBLE--like it just grew a deep moldy scum ALL OVER IT. Not to worry--this is the same result you'd get doing a rust blue, only the scale is softer and happens a LOT faster.

Wipe it off as per the instructions with the bluing. Then, card with a soft wire wheel or you can do it with 0000 steel wool.

The active rusting agent in Oxpho-Blue is phosphoric acid, and it REALLY does a good job. If you want to do more than one gun--and you don't mind the extra cost--Brownell's has complete bluing outfits from small and portable to any size you care to make. They also have a cold-bluing kit available (using another one of their products, Dicropan IM) that is suitable for commercial use.

James K
September 9, 2010, 02:57 PM
If one is going to go to those lengths with cold blue, why not buy a good rust blue (usually sold as Belgian blue) and have a durable job rather than one that is shallow and will come off with a little oil or rubbing? The rust blue will require the same process of boiling and carding, but is deeper and the result will be a lot better.