Alright, I'll admit right up front I didn't read all the posts and I believe the first choice--the 7-08--would do fine, but, I have a K95 coming this month that I envisioned for just such a job. While I ordered the more pedestrian 30-06, the 7mmx65R
you mention is probably a more romantic and certainly just as practical a choice as far as capabilities.
I also have a Lex Webernick rifle but your 300 Wby is no way as light and handy as the K95 which would be a premium consideration with me and provides several options packing-wise; that said, none of your rifles could be said to be bad choices.
Sorry to waffle, but I would probably carry the K95, invest in another set of Blaser rings/base combo- carrying an extra scope. I know about the cost but I also know about the cost of a Dall sheep hunt.
Your welcome! Good hunting!
