Limapapa;
This agrees exactly with my experience of heat treatment of steels over 35 yrs in a machine shop. This was on both through hardening & case hardened steels, though "Not" shotgun actions. In my experience a piece of steel just "Does Not" go through a furnace & be brought above its critical temp & then be quenched "WITHOUT SOME DIMENSIONAL CHANGE". Ceertainly carelessness in temps can magnify the problems, but it must be understood if that critical temp is not reached then all the hardness of the case will be "Tempered Out" & the part will only be "Colored".
I feel any person performing this work who does not make their customer "FULLY AWARE" of the possibilities is a "SHARK" (If the shoe fits Wear it). The customer can then make their own decision & bear the responsibility.
