I would go with either. The elk won't know the difference. A 160 grain premium bullet in the 7 RM, or a 165-180 gr premium bullet in the .30-06 will have the same effect on an elk if you put the bullet in the broiler room... A dead elk. My family has used the .30-06 almost exclusively for years, and I can't complain. Under 300 yds there is virtually no difference between the two. Beyond that shots begin getting to risky anyway. Flip a coin.