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6.5mm 147gr eldm @ 2700 fps gives 1772ft-lb @ 300yd and 1598ft-lb @ 400yd. 308 168gr eldm @ 2700fps gives 1826ft-lb @ 300yd and 1585ft-lb @ 400yd. So a small energy advantage to the 308 at 300yd...

308 has more energy @400yd but more wind drift. A 168 eldm driven hard out of a 308 would be a devastating round in the mountains. But agree the 6.5s are very good