Homemade Hot Blue Formula

Original Post Courtesy of Blair Emory
[my comments in brackets - KM]

All "bluing" is really blacking. The blue shine is due to additional chemicals such as manganese that are added to the mix. They are usually less abrasion resistant than blacking and perforce are thinner to give the blue refraction. They are a lot fussier to do and the results vary more than straight blacking on different metal alloys and heat treatment in my experience. I generally use a lye, fertilizer mix that gives the hardest blacking I have ever seen and it so simple anyone can do it, plus the ingredients are available at the hardware store rather than paying UPS hazardous shipment fees.

Bluing Setup:

Here is a photo of my bluing setup. This is all I've needed to blue several pistols.
         

Another excellent site which gives a sodium nitrate recipe for these salts, and sources for the chemicals:
http://www.blindhogg.com/homemadesalts.html

Guns I have blued with this formula: