"And in a receiver the case hardened outer metal increases the the total yield point of the receiver. Pounds per square inch tension is not the only factor, it is how far that tension is from the zero stress point of the beam."

Case hardening has nothing to due with 'yield point' if your are referring to the point where steel in tension trasisitions from elastic to plastic deformation. Case hardening affects the hardness of the surface and the values are not additive.

"So it is not a simple case of calculating the percentage of the cross sectional area that is case hardened and pro-rating it's increased yield strength into the total strength of the action."

I have never heard of a calculation like that?
Both Hardness and Yield Strength are measures quantities and are not calculated nor is there any quantity defined as "total strength".
-Dick

Last edited by Dick_dup1; 06/09/12 10:53 AM.