rust blueing

[hortonstn]

well guys, last night i tried it i put the solution on over a period of two weeks
everyday and boiled once the barrel turned out beautiful, can't thank you for your support enough,
i used to blue modern firearms with hot caustic blueing methods, but really like this for the muzzleloaders,
the only question is many people clean their barrels inside with hot water  so
why is it important to plug the bore, is this just so the acid won't get into the barrelwhile rusting?
thanks again
paul
if i ever learn how to post piks i will do so

[Dphariss]

An Aussie gunsmith over on nitroexpress has been experimenting with Nitre bluing, using heat and salts. He said the finish appears to be as durable as rust bluing.  Although the process was withheld, I assume it is a submersion in the salts which are heated to temperatures giving heat colours. The salts then 'impress' or 'fix' the colour in the material.

I nitrate blue a lot of stuff, I do springs in a saltpeter bath I think its better than simple heat blue but still pretty fragile. The only way to get decent durability is as per the hand written instructions in Madis' "Winchester Book". Nitre blue then coat with oil and then heat to smoke off the oil. Winchester baked the oiled parts in an oven.
The document also states that 1/10 to 1/20 by weight of "Peroxide of Manganese" be added to the nitre bath.
Still nothing like rust blue which is more durable than browning in my experience.

Dan

[Daryl]

tks

[Dr. Tim-Boone]

Paul,
I too use galvanized rain gutter from Home depot that I soldered up and heat using a double burner propane stove I picked up from harbor freight. I use the stuff chambers sells with degreaser and browning solution in one called "Laurel Mountain "browning solution. This is a California rifle I built that I rust blued the barrels for.

OK, so I went to home Depot, all they have is light metal (Aluminum) or PVC gutters. The aluminium is painted white on the outside... so I guess that has to be burned off with a torch outside before trying to use it on the wife's gas range eh??  Where did you get galvanized steel???

[Model19]

I thought heating galvanized steel like that was a bad idea due to poison fumes generated.  Zinc was the culprit. 

[kutter]

well guys, last night i tried it i put the solution on over a period of two weeks
everyday and boiled once the barrel turned out beautiful, can't thank you for your support enough,
i used to blue modern firearms with hot caustic blueing methods, but really like this for the muzzleloaders,
the only question is many people clean their barrels inside with hot water  so
why is it important to plug the bore, is this just so the acid won't get into the barrelwhile rusting?
thanks again
paul
if i ever learn how to post piks i will do so

I never plug the bore(s) while rust bluing. Just a pain to do so and the chance that it's not water tight is more of a threat to the bore rusting than leaving it open.

Plus plugs blowing out in boiling water isn't fun.

Careful not to get the soln inside the bore in the first place. The application shouldn't be so heavy that it runs and drips all over anyway.

I wipe out the bore after it's boiled and carded (no oil) and have never had a problem.

The only time I do anything with the bores is when damascus finishing as the bbl(s) must go into an etching soln between coating. That must not get at the bores or you'll have a mess on your hands.
Instead of plugging them (again not knowing if they are truely secure),,I coat the bore before I start the process with nothing more than shellac.

Several coating applied with a cleaning rod and swab, letting them dry in between coats so they layer up instead of push out during application.
Any over spill onto the outside is cleaned off with acetone or laquer thinner before beginning.
The coating holds up perfectly through the boiling, etching and wet carding sessions needed for the damascus finish.
I may recoat once during the cycles just for peace of mind around coating #8. It takes around 15+ coating & cardings to get a good damascus finish.
No boiling if you want brown damascus.

After I'm done,  remove the shellac with a good brushing with laquer thinner and patches wet w/same. It takes quite a bit of work to get that stuff out.
Never had a bore damaged by etching or rusting soln.