Read the first post, not the whole thread, but... I had the same dilemma, build a long range elk rifle. It was 300wsm and it is a shooting sob as far as I am able to accurately shoot it. It was a custom rifle, so I know it's solid, but loading for the 300wsm is a dream and it's performance out to 1000yds is outstanding. I spent last summer shooting it at ranges from 500-1000 and when the time came to take a shot on an elk last fall with it at 720yds, there was no hesitation at all. One shot, one step, dead bull. I loaded 168 Berger VLDH and it took out a mature bull, top of the heart (my mark was for 725, not 720) and both lungs and passed thru.
I am switching up to 200.20x for some long range competition this summer and that will be my hunting load as well in the fall, I'm sure.