Ted, I can't improve on Miller's explaination.
Generally speaking, we would expect that the total recoil would be much more dependent on the energy content of powder charge in the load rather than the pressure curve (assuming reasonable burning of the powder). Looking at various loads with powder of varying burn rate and similar MV shows that there are many ways to "skin the MV cat," pressure curve wise. However, I, for one, hold that there may be people sensitive enough to sense felt recoil from the gun's rearward acceleration, as opposed to the gun's rearward velocity as in total recoil. If this is true, then it may be that pressure peaks in the forcing cone cause rearward acceleration peaks of the gun and are detectable by certain sensitive shooters.
In the above context, it may be that tearing off the end of a hull indicates a higher pressure (it may not be necessarily so, though) which might show up as more felt recoil to a sensitive shooter without an increase in MV. However, I don't thing either felt recoil or MV increase/decrease is "necessarily" so. It is a complex question to which we are short a few pieces of data.
Not to beat a dead horse, but I think it is critical to not think in terms of pressure but rather the resultant charge acceleration. AND, as Rocketman has noted, acceleration per se does not make MV.
It would be fairly simple, but probably expensive, to build a rig to measure the
RESULT of all of those bits and pieces. And fun as it would be to quantify and chart all that I'm guessing the Lotto God would have to intervene for me to do it.
WtS
