The pressure applied to the bolt seems like it could be roughly gauged by felt recoil.
Not at all.
Peak pressure, which is what stresses the action, has nothing at all to do with recoil.
Pressure and case head (not rim) area are what you need to look at, this determines the "bolt thrust", or force pushing the bolt back. A larger or smaller case rim does not affect bolt thrust.
Recoil is a totally different thing, related to bullet weight and velocity, powder mass, and muzzle pressure.
