I have shot half a dozen cows with a 243 using 100g partitions, they flopped. Shots were 100 yds and less.
The two most popular elk rifles in Az when I was living there was a 30/06 and 270 win.
I shot two big bulls with my 7 Mag using the old 140g NOsler ballistic tips loaded to 3200. Shots were 150 yards, mid body hits, and they were dead when they hit the ground. Two guys I hunted with used BARs with the same bullet and load. Their comment was the ammo killed like lightening.
I think that poor hits on elk make for a lot of good stories, and creating the fear that a larger caliber is much better. A poor hit is a poor hit no matter what the caliber.
For the average guy, a 300 Winchester or a 300 Weatherby mag loaded with 180-200g partitions would be a marriage made in Heaven, and for a 30/06, the 190g Hornady btsp will the job done!
Except that the average guy likely won't shoot either one very well.
