Okay, i am sure this has been aske a thousand times.
What is the best way to cold blue a set of barrels off an old double gun?
I also to do the same with a brand new flintlock barrel.

I have tried several bcold blue solutions and they all suck.

You have answered your own question....cold blue is a very poor substitute for real blue. You might try Mark Lee's express blue. It gives a nice finish if you are not feeling like giving rust blue a go. Either will be far superior to any cold blue I have encountered.

so i did some searching on the 'net and several hits came up for a product called Belgian Blue. It was originally made by Herters and is now offered by Brownells.

Does anyone out there have a bottle of this?
If yes, coulf you please tell me what are the ngredients?

I don't want to buy more of the same if it has the same ingredients of what I already have.
Thanks!

Mark Lee's and Brownell's Belgium blue use the same process and are likely very similar in chemical composition. I do not believe either lists the ingredients. Mark Lee's does not. I do not have a bottle of the Brownell's on hand but I believe it will not be listed.

Belgian Blue does have mercury in the formula which is verified when it turns any gold inlay to a very shiny silver or mercury color...by amalgamating with the surface of the gold. I have used this blue a few times and it worked quite well for me. Plan to use it again soon.

For touch-ups or smaller parts, the "cream" formula of Brownell's "Oxpho Blue" works great; it is almost the consistency of syrup, so it clings to round surfaces better than a more viscous liquid. I found it works best in multiple applications and with the item heated with a heat gun.

Longest barrel I did was 6" on a blackpowder boot pistol and that came out amazingly well -- but I have not tried it on anything bigger.

Good luck.

Old No7

Belgian Blue. This is in fact an old formula, purchase a copy of Firearm Bluing & Browning by R.H.Angier. It won't cost you an arm and a leg available on ebay. This will give you practically every usable bluing and browning formula known to man. With lots of useful information as well. Including the Belgian Blue formulas.

Belgian Blue (Herter's) was an Express Rust Blue.
Boiling and carding in betw applications of the soln to the warm surface of the metal.
'Express' in the fact that you do not have to wait for the soln to rust the surface of the metal.

The older Express Rust Blue solns (sometimes called Quick Rust Solns) often had Mercury compounds in them to make them work well,,that is rust. Mercury Bi-Chcloride was the most popular one found.
Up into the 60's and even 70's these solns were sold with the Merc content and no one said much.
Then the Green movement got it's start and the surefire to rust recipes were changed.

Even the old BirchWood Casey MuzzleLoader Barrel Brown,,the stuff where the hobbiest just heated the bbl warm w/a propane torch and swabbed the B/C on to get an instant rust forming. Then card it back, reapply, ect till it was how you wanted it.
That contained Merc BiChloride too. That's why it worked so well.
It made for a great Express Rust Blue soln! But somewhere along the way, probably the 1980's they changed the formulation to exclude the Merc.


Slow Rust Blue is the other side of the Rust Blue processes. The soln is applied to the room temp surfaces of the metal and then allowed to set. The rust forming naturally (Slow).
It can be accelerated by controlling the temp and humidity around it so that a coating of rust forms as quickly as a couple hours.
None of the Slow Rust Blue soln's I've used have had any Merc in them (that I'm aware of).

I stay away from any of the soln that may have mercury in them even though they work well.
Too many years exposure. Yes it does effect you.

I did try the Brownells 'New' Herters Belgian Blue when it came to market some years back (90's?). I figured by then it was reformulated to keep the MErcury out of it.

I tried a small bottle. Warmed a piece of brass and swabbed it with some of the soln and there it was. The nicest brite silvery plating on the brass. I figure it's mercury,,I'm not about to dig any deeper to find out, and they ain't saying what's in it other than it's Original Formula. Guess I should have figured it out.

Mark Lee's Express Blue soln for that operation and Laurel Mtn Slow rust blown (boil for blue) for slow slow rust blue is what I've used for the last 30 years or so.
No mercury in either. You can coat right over gold/silver inlays and not fear that they'll come out of the tank mercury plated. The mercury plating does NOT card or rub right off. It is there to stay unless you polish it off. You can imagine the problems.

In one shop I worked in early on they used Belgian Blue and discovered the plated inlay problem.
The TroubleShooters from the front office made a first attempt at removing the merc ... heat the tiny 14k inlays with the pin point flame of a torch. That did work a little. Burning off mercury in the shop,,that was a smart move looking back.

Then to finish off their fix, those in the know decided a rub down of Nitric acid on a small patch would polish them up nice and sparkly clean.
When they got done playing around destroying things,,
The parts were stripped and back to the engravers to polish repair the inlays and surrounding work and a better bluing process sought.

Swab on chemical cold blues...the only thing I have on the bench is a bottle of Oxpho Blue (Brownells) It does a decent job for screw heads and pins and the like on a touch up job. It certainly has it uses.
But anything else gets the full treatment.
Swab on cold chemical blue is nothing to do an entire gun with IMO.
It may look pretty good in certain light, but there always seems to be excuses for the overall way it looks.
You don't want to have to make excuses for your work.

Thank you so much for that detailed reply.
Perhaps I missed something.......
you said that anything more than pins and screw heads gets the full treatment: what is the full treatment?

That would be a Polish, then either a Slow Rust or Express Rust Blue.

7shortmag,
I threaded a pile of pistol barrels and made/knurled the thread protectors for a dealer friend. I used "Oxpho Blue" for the thread protectors by placing a quantity in a plastic container and submerged the thread protectors in it. Good even color resulted. Instructions say degreasing is not necessary, but I always clean with acetone. When I make screws/pins I do the same thing. Don't put any parts into the main container, it will cloud the solution. A late friend( 22 rifle/shotgun gunsmith)did really nice work with it by going over and over it, until satisfied. It took as long to do a complete rifle as it takes me for slow rust.
Mike

I have seen nice results by a friend using Mark Lee's Express rust blue.

Is the Mark Lee express finish durable though ? I have a little .22 bolt action to blue. I went to the chemist to have my old bluing formula mixed up. I know it works because i have used it so many times before. Anyway the chemist cannot and will not make it up as eu rules mean he is only permitted to sell pre-wrapped medicines, so he does not stock chemicals anymore.

Also as it contains nitric acid and copper sulphate (thats all it is really) he is not allowed to sell these things either.

So the only bluing solution i see for sale is Mark Lee's express stuff.

bonny,
If your "chemist" is in the EU, he should be able to get German formula slow rust solution. A liter has lasted since 1982( I'm not a commercial enterprise) and it works very well for me.
Mike

It cannot be sent via courier, no liquids. Even the uk suppliers such as Dyson will not send bluing solution off the mainland uk. The chemist/pharmacist i used to use was an ancient large animal veterinary practise. Nothing was too much trouble and the people there were professionals, not glorified counterhands.