.30-06 for a one gun hunter in CO or North America for that matter IMO.
On a budget I'd buy a Savage 16/116 FHSS. I prefer a plastic stock in the field and a stainless barrel. Both offer advantages in bad weather. Savage is know for out of the box accuracy. They also have a unique trigger design.
I hunt with a Browning, Stainless Stalker .30-06 that I like very much. If I would have had a couple hundred more to spend I would have got a Kimber Montana.
Pay attention to the safety designs of different models. Make sure you like that aspect of what ever you choose.
Scope, I'm a Leupold user and have no complaints. Nikon, Burris, and Vortex would be other companies I'd look at personally. You generally get what you pay for there. You want something with a 3-4 power low end as that is most likely the setting you'll take actual hunting shots with. Higher setting are nice at the range for sighting in. I'm not a fan of the fancy reticles personally. As a rule of thumb I'd plan to spend 50% of the cost of a rifle on the scope or more. Sight yourself in a 200yards and know how to adjust each way in the field based on ballistics of your hunting rounds.
All and all most guns shoot better than the hands they are in anyway.
You want to budget a good pair of binoculars too if you don't already have some.