Randy, the 8 twist is what you want to shoot the 105/107's out at 600yds and it will be just as accurate at 200-300yds with those bullets. If you're wanting to shoot lighter (70gr?) varmint bullets at shorter range, the 8 twist will stabilize them, just not as good as the longer bullets. It should stabilize the lighter bullets at least 1/2 minute of gopher.
A friend is shooting 68gr Barts out of a Savage 6br 8 twist at our BR matches and they shoot 1/2" to 3/4" at 100 yds
I've got a 8 twist 22-250 that likes the 80 gr BergersVLD"S. It will shoot 55gr Vmax into 5/8"
Good Luck
Greg