Thanks for the explanation, Sqlbullet.  That is the info I was looking for.  It clears up a lot of my confusion and I think I'll try out your process just to set my mind at rest.  I assume from prior posts that people normally look at a group of 5 or so shots to see if any of the cases are approaching max rather than just looking at one case and calling it good.

Thanks for the replies, folks.  Much appreciated.  Now if I can just figure out how to keep the brass within the same zip code, I'll be doing great :-).

I've read quite a number of posts where the shooter mic'ed the case to determine if the load was nearing max pressure.  Can someone explain the process?  I've got a good set of micrometers, etc. so doing the measuring isn't an issue but understanding what I'm looking for escapes me.  I assumed (probably wrongly) that when fired, the brass will expand to fit the chamber and then shrink slightly due to elasticity.  But how does the max load affect this?

I'm shooting 165 gn Zero JHPs over 11.8 gns of AA#7 to get 1300 fps out of my Witness Match but I'm worried I may be pushing a limit somewhere even though my primers don't show any flattening.  Thanks for any insights here.