the use of the term torch case hardening infers that the heat source is uncontrolled. i agree, uncontrolled heat applied to a shotgun receiver is a bad idea. almost as bad as heating the receiver up to around 1600 degrees, beyond it's critical temperature and then guessing at what is the correct tempering procedure.
as for research, it ignores reality. the reality is that i and others with far more experience than myself, have seen too many fine pre war guns ruined by high heat case coloring mechanics, who guessed wrong, when they attempted to temper the receiver metal after the high heat bone charcoal re hardening process was completed. the wisdom of experience says not to alter the original factory heat treating in a vane attempt to restore case colors.
Last edited by ed good; 11/26/09 11:36 AM.
