I have been shooting the complete Model 3G rifle for Team Stag Arms on the 3 Gun Nation tour since August of 2011. The fluted 18" HBAR bar with a 1:8 twist is good for MOA accuracy with match ammo. My two rifles both love the Black Hills 69gr Sierra Match King ammo. I have shot several MOA groups at 300 yards with that ammo off of a surefire 60 round mag as my only support other than my elbows. With the same shooting style I get 1.5-2 MOA accuracy at 300 yards with PMC, Federal or most other inexpensive 55gr ammo. I have never even shot the gun off of a rest or even bags because I don't get to shoot that way in matches. I shot a few hundred rounds off of a bipod recently and those 1.5-2 MOA groups shrunk as you would expect.
So to answer your question about using it as a hunting rifle you should be good to go and will likely pleasantly suprised with the rifles accuracy.