I've never hunted in Co., so I can't tell you why you would need more than a .308. Can you tell me critters, distances, etc. I don't get into all these new cartridges, bullets, etc. The 300wm. with ballistic tips shooting a high shoulder shot has been just fine for me.
Me, I've shot a 300 wm for 25+ years, before that a 300 whby. The only reason I changed, I couldn't get the proper eye relief for my eyes on the whby. with a new scope, I had to completely change guns, went to a Steyr, haven't looked back. That Steyr in a 300 wm. has some bad juju. They didn't have all these new fangled cartridges back then, but, I buy off the shelf, so if I couldn't readily find ammo, these new cartridges would have been out anyway.
I'm not a huge guy, weigh less than 165 most of the time, I don't use a break, I do have a limbsaver pad on it, and I added a neoprene comb riser kit to it (I'm running a 56mm objective, so had to go with higher rings - I shot without a comb riser for at least 23 years without one - it has made a difference settling in at the range -- I can't tell a difference in the field). The Steyr won't win any beauty contests, but the animals have hated it. I don't carry a gun for others to enjoy, I carry one to kill. I don't carry tools for others to envy, I have work to do.
If you really want a mountain rifle, Stery makes a pure mountain rifle in .308. I've shot a couple, those things are fast as lightening coming up to the shoulder. You also may not find a nicer factory trigger than a Steyr's.
Have you looked at the Sako offerings? Just throwing it out there.
