How hard is it to do a rust blue?
It's really quite a simple process:
- Take the gun apart
- Strip the old finish
- Clean the metal
- Let the metal rust (with a little help)
- Boil the metal to turn it black
- 'Card' the converted rust (brush off the powdery black stuff)
- Repeat steps 4,5,6 at least 4 times
- Soak the metal in oil for 24 Hrs
- Put the gun back together
For me, the most challenging parts of the process are the diss/re-assembly of the gun. The actual rust bluing is pretty much just waiting, degreasing, and boiling water.
Here are a few good articles to get you more details, but it really isn't much more complicated than that. It's easy, but will take several days (it's why the call it 'slow' rust bluing).
In my opinion, the extra time is really worth it. Rust bluing provides a really tough (for bluing) finish - a good bit tougher than commercially hot salt blued finishes, in my experience.
Good luck to you!