I'd like to give this process a try but I am totally in the dark
as to how it's done and what chemicals are used. Does anybody have the scoop on this ?
I could go with a rust blue on my project, but I think the nitre
blue would go better on the action parts of a roller I'm doing.

Brownells offers the salts pre-mixed for this process.  Go to (You need to Login or Register to view media files and links) for the full instructions.

David

I'm finishing up a high wall project and have always admired and wanted to duplicate that luster or sheen that is found on the receivers on highwalls, 86's, 92's, high grade model 12's and others that cannot be duplicated with a hot dip blue.  Everything I've read and heard about nitre blue is that it is not as durable as other finishes.  In the Madis' book, it explains the nitre blue process and mentions the use of adding manganese peroxide to the mix.  Does anybody know if this makes it more durable? Also, does anybody know if this was the actual process Winchester used on these actions and is this why so many of them that were handled seem to have the finish almost look like it is flaking off??  Could Winchester have used an entirely different process for these actions such as charcoal bluing or heat treat bluing of some kind?  The process used on Model 12 Trap and Skeet grades made in the 40's and 50's seem to have a type of blue that is different than a hot dip blue and gives that neat lustre yet is very durable.  I took a class some years ago in rust bluing and the instructor and I had a discussion on this and he thought it might have been a gas blued process.  Anybody have any information about this as well as know of somebody that can duplicate these colors and lustre?  Granute, did you follow through with your project and how did it go?

Mr. granute,
I am currently Nitre Bluing using the Brownell's product.  A few things that I have learned by hands-on, may be of help to you.  A bullet casting thermometer is mandatory as 25 degrees either way can make a significant difference in the color.  Parts which have a substantial variation in thickness or mass can be tricky because of the difference of heat soak time.  It is beneficial to pre-heat the parts using a counter top toaster oven (obtain this from the goodwill, not the wife's kitchen  )  This also drives out any residual moisture which would prove disastrous if immersed in the salts.  The parts should be blued immediately after polishing, the better the polish, the better the peacock, in this application you can use a grease based compound as it has no affect on the outcome.  Sometimes applying a light coating of oil to the part before immersion will give you a darker blue, depending upon the alloy.  I dropped my parts directly into rain water from the bluing tank, this helps stop the process especially on heavy parts.  And, as always do not forget the safety gear and lock out all guests.  There's my 2 cents worth - good luck and enjoy yourself.

HST is 100% correct --- the finish you are looking for is Carbonia bluing and the favored source is non other than an ASSRA supporter "Classic Guns" of Beecher , Ill.  FWIW,   Ken