Actually, this topic is fairly interesting. I'm speaking of superficially recoloring for purely aesthetic purposes. I'll differentiate this from high temp torch processes that alter the temper of the steel. These low temp processes may be suitable for lower value guns, those which the expense of true case coloring would clearly be uneconomical. My collection of old gunsmithing books are full of these processes, and some firms are offering such things as Tea Staining as a way to provide at least some degree of coloring on guns. There is also another company offering a "Patina" series of products for superficial recoloring.

https://steelfxpatinas.com/shop/steel-patinas/gel-patinas/color-case-hardening-patina-kit/#reviews

For guns of relativly low value and/or collectability, and as long as the color recreation is fairly accurate, these processes provide a reasonable option. Of course, "full disclosure" is essential when selling the gun.

So, in order to advance the thread, anyone know anymore low temp recoloring processes besides Osphoblue and a heat gun?

Regards
Ken

I prefer wood to plastic, leather to nylon, waxed cotton to Gore-Tex, and split bamboo to graphite.