From your list my favorite is the 280AI. But I would also consider the .257 Wby, 6.5/284, 6.5-06AI and the .264 Win. all lighter recoil and worthy to well past what your considering. The downside is barrel life with the 6.5-06AI maybe doing better in that department than the others. The 280 AI covers these others with 120s @ 3,300 & 160s @ 2950 fps, not as flat shooting but good to 300 with no holdover.

Not sure about barrel life on the .280 AI but should be as good or better than the 7RM maybe significantly better. I'll know in a couple 1,000 more rounds.

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