doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com How is nitre bluing done.

I would like to redo the original nitre blue on an Alex Henry
double rifle trigger guard. Can it be done by an amateur?

LD1, you can but by the time you have got the material together and a heat source you can have it done here for less money. They do good work and are close to you.
http://www.classicgunsinc.com/

JIm

British shotgun and rifle trigger guards, top levers, and floorplates were not nitre blued; they were charcoal blued, a very different process. Nitre blue is a form of "temper" blueing, where the temperature of the metal to be blued is controlled by a molten sodium/ potassium nitrate [nitre] bath. This results in a very bright 'fire' blue, or a purpleish blue. A charcoal blue is similar to a color case where the parts are heated in powdered charcoal. The colors are very different, and the wear qualities are as well. A charcoal blue will wear much longer than a nitre blue. Doug Turnbul's "carbonna" blue is very close to a British charcoal blue, but I have noticed a slight color difference.
I hope this helps, Mal

Wasn't charcoal or carbona bluing more of a standard finish on guns right before and right after WW2 by predominately American companies? I thought most British furniture was blacked using the rust bluing method. I would say most all the vintage Brit doubles I own have rust blued furniture.

When Brits "refresh" a double gun, they often like to nitre blue the screws and pins, not all the time, but I've seen enough of them done like that to form an opinion.

Here is a Cogswell & Harrison that has its furniture Carbona blued and the screws Nitre blued. If I had to do it all over again, I would've had the furniture rust-blued instead. The Carbona blue is too shiny, looks too much like hot blue for my taste. I prefer the soft-velvety sheen of properly polished rust blue.

My niter blue is almost black and wears better than charcoal blue, it is NOT just heat blue. The stuff Brownells sells as niter bluing may be causing confusion. The color is dependent on time so an early removal could result in heat colors.
bill

LeFusil,

I have a beautiful hammerless best quality Alexander Henry double rifle that was redone in England. The trigger guard and butt plate look like the carbonna blue that you show on your Cogswell. I also have a totally original Alex Henry in excellent condition. However, I can't tell what type of bluing was used 120 years ago. It definitely is not shiney like carbonna blue.
How shiney would charcoal bluing be?

Charcoal and Carbona blue are the same thing. When finished using this method, the parts are just too shiny for my liking and in my opinion do not look right on a British gun. I think the proper finish would be rust blue. Rust blue can be also have too much shine if the metal is polished too much. But done right...it will have smooth velvety sheen (look at the pics of Mr. Hurst Baker barrel in the "Mr. Hurst barrel scratching" post". Thats the way it should look.

http://www.doublegunshop.com/forums/ubbt...age=2#Post75515

I agree with Bill here, as I believe we both use the same method that Oscar Gaddy used and it involves more heat and more time in the bath,....the colour achieved is a dark blue-black that wears very well.
I've been doing a bit of research on the subject the last few days and I believe that Carbonia blue and Charcoal blue are not the same thing
Here is a sample of my niter blue for comparison,....Parker DH guard and butt plate just coloured yesterday

CJ

Could you tell me the temperature, and the length of time in the bath? Your results look good.
Mal

Carbonia as I recall was a "Trademarked" name applied by the American Gas Furnace Co. The work along with burnt bone was placed into a revolving retort after which a chemical which would gasify was introduced during the heating process. This was I believe the standard process used on those beautiful old S&W frames. No I don't have the chemical formula.
CJ; Does this agree with your research on the subject? Except fot the S&W connection which is based purely on memory, the rest is from an old Machinery's Handbook.