In Marshall Stanton's great article on rebuilding the Marlin trapper carbine, he uses stump remover for bluing. Does anyone know the melting temperature of the Green Light brand potassium nitrate?
Thanks,
Keith

Welcome to the forum grandpa. I don't, but here's a link to some nitre blueing chemicals from Brownell's. If you send marshall a PM he probably can help you out.

www.brownells.com/aspx/ns/store/ProductDetail.aspx?p=1105&title=NITREBLUE%7e+BLUING+SALTS

Bluing salts typically function in the high 200 degree range. Potassium Nitrate is Potassium Nitrate, regardless of brand.

Bluing salts typically function in the high 200 degree range. Potassium Nitrate is Potassium Nitrate, regardless of brand.

Looks like these salts need to be a little hotter.

From Brownell's catalog.

Turn parts and small pieces a deep, rich, lustrous blue with a finish that's tougher and prettier than most of the cold blues. The process is really quite simple: Heat the salts up to 570° F. - 650° F. (they are NOT dissolved in water, they're used straight). Dip the parts in, watch for the color change. Lower temperatures give a "straw" color like the older Luger parts. As an added bonus, the salts can be used for the drawing operation when heat-treating springs and parts.

I highly recommend nitre bluing for small parts. It's easy, and gives beautiful results.

Potassium nitrate crystals (stump remover) are easily melted over a heat source like a camp stove. I believe Brownell's to be correct in their temp range -- it'll melt at around 570, and your best bluing results come at around 600. The process is virtually impossible to screw up. Spend some time in preparing and degreasing the parts, and BE CAREFUL -- the stuff's HOT, and even a drop of it will give you a very painful burn. Trust me on this one! :eek: