If you're doing what many of us do, and reloading 2 3/4" hulls and shooting them in guns with 2 1/2" chambers, a 10,000 psi reload per the published recipe can easily exceed 11,000 psi because of the extra hull length. It's safe enough to reload 2 3/4" hulls for 2 1/2" guns, but in that case you need to build in an extra safety cushion if you want to make sure you stay below the established service pressure for the gun in question.
Larry, it puzzles me that you and others so actively promote the practice of loading 2.75" shells and guesstimating pressures in 2.5" guns....ESPECIALLY the very people who are so concerned about pressure in the first place.

If you want to keep readers on the safe side, maybe you should advise them to use published data expressly for loading 2.5" shells. If people don't want to use that, they can simply pick any 2.75" recipe at any pressure level they like, trim 1/4" off the hull and either roll-crimp or use a Hartin crimp. Pressures changes will be virtually statistically insignificant.
Makes me wonder, what fudge factor should I use for loading 3" shells for 2.5" guns? Or has that article not been published yet?
Yours in candor, Mike