Do we agree that the case shell is on the order of 0.002" thick (about the thickness of a human hair)? If so, and if the the "hard" shell had ten times the force per unit thickness trying to return the action to OE dimensions after yielding of the core, the first 0.020" of the "soft" section would balance the "hard" case shell. The "soft" has a whole lot more "meat" than does the "hard" shell.

Yep, a "soft" action will bend and spring back under firing stress. This is for the simple reason that the strain (deflection) does not exceed its yield strain. Note that stress and strain are somewhat interchangable as they are related in a very predictable way. X amount of stress will produce Y amount of strain. Y amount of strain indicates that the metal has X stress applied.

Good discussion!! Keep going until all understand.

DDA