3000 FPS "easily"? I don't think that you're being realistic. Long range competition shooters are pushing the high end and they seem to be sticking to 2885 to 3050 FPS in custom barrels that are mostly longer than 26 inches using the lighter 139 to 142 grain bullets.
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If the long range competition shooters are pushing those kinds of speeds in their custom barrels then I'd bet that a commercially produced rifle with a tight chamber (based on who knows what bullet profile) would produce signs of high pressure at those same velocities. Your using a different brand bullet and that will have an effect on the chamber pressure when you are pushing the top end.
3000fps should be easily attainable. My 26” Hart barreled 6.5-284 shoots 3072fps with an SD of 4fps. This is with 140 Bergers and RL22.
I have very light ejector marks. I’ve pushed it over 3100 with a few loads but started getting pressure signs and SD went up noticeably.