External hardness testing of Mauser recievers is an exercise in futility. Yes, they are machined from mild steel forgings. The key to their strenght and longevity is that they are "pack hardened" on critical internal surfaces, mainly the lug seats and buttresses. The only way to actually hardness test a mauser is to destroy it by cold cutting it in half. All that I've seen done this to were "carburized" to a depth of .015 to .020".TRX wrote:Kuhnhausen said that he sent samples out for metallurgical analysis, and most old Mauser actions were 1025 or 1030 steel, shallow case hardened.
That's one step up from chicken-wire grade steel, and a long, long way below 4140.
I would personally never build a rifle that the intended new cartridge exceeds the original designs pressure parameters.
JM2c