.308, 7-08, 30-06, etc, etc, doesnt matter a whit, with a well-placed shot the elk will never know the difference. As with all hunting, it is all about the well-placed shot, everything else is just hot air.

a premium bullet is of great importance, needs to hold togeather to penetrate deep. a 7-08 will go all the way through a moose......or stop at the shoulderblade. bullet construction counts even more with a smaller less energy round. that being said a 23 will knock them dead if you hit both lungs and slip it between ribs.

dave