is the .270winchester not an option for you?
long action, high velocity, 2015 modern bullets and I assume you can shoot accurate under pressure of a high country sheep hunt to place a shot in the vitals at the range you stalked into, beit 200 or 500, your call.
I know with mine, an with suitable bullet I could kill a goat at 400, with more practise I'd slip one into a fallow deer (goat sized) at 500 an that would be far enough.. that's with extreme practise a new scope bla bla.... but im just saying... its capable?
WL
I didnt consider the 270 beceause I already have one. I think it does as good of a job as a 7mm rem mag