One of the best brush guns I' ve ever used is the Ruger M77 RSI in .308 Win. It has the full-length, Mannlicher-style stock and is very quick handling. It also is capable of longer shots and should be perfect for what you describe. I have taken deer and elk with one using 150gr and 165gr bullets, respectively.

A leupold Vari-X II 2-7 scope on top would make a very nice rig, indeed.