Don, are you proposing, with the above, that there is are no pressures exerted against the breech by the shell head? I think two debates are getting mixed up here. Of course, there is no recoil where there is no flow, but point is that, in a shotgun, there is flow, so there is recoil. I'm just not sure what point you are making here.

Originally Posted By: Joe Wood
In other words, if two loads have the same ejecta velocity but one develops 2,000 psi higher pressure do the two have the same stress on an action?


No, the two do not exert the same stress on the action. With two loads that are calculated to have exactly the same recoil energy, the one with the higher pressure will stress the action more. Not because of higher recoil. Again, the recoil is the same. But, because of the higher force exerted against the breech by the shell head in the brief moment that the pressure is still rising, and peaks. Regardless how long or short the duration of that event.

SRH

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