The Hornady manual says 53.2 gr. Rl15 does 2300 FPS from a 22" barrel (Remington M700) and 55.1 gr. 2400 FPS which is the max in the manual. That probably puts you at 2350 FPS or thereabouts. Not sure what you mean by slightly proud primers??? Are they flattened some? Protrude slightly from the base of the shell? I doesn't surprise me that the fired shells are "hot". How quickly do you eject them from the rifle after firing? Have you ever picked up a freshly ejected .223 round from an Mini 14 or AR15. They're hot enough to blister the skin. I load and shoot three rifles in .35 Whelen and while the cases are warmish, I've never noticed them being all that hot, temperature wise. I'd be interested in hear how the test with the factory loads go.
Paul B.

Our forefathers did not politely protest the British.They did not vote them out of office, nor did they impeach the king,march on the capitol or ask permission for their rights. ----------------They just shot them.
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