Jeez at the misinformation in this thread! If you plan on shooting ground squirrels or P. dogs, get a Vias muzzle break, otherwise you will be chasing your tail.
It took me 10,000 rounds on ground squirrels and p. dogs to figure this out shooting high power scopes.
If you shoot a 6x-10x, then all you see is the animal fly, you are shooting center of mass, really not knowing where your exact hit on the animal is.
For instance, on a broadside shot, I will sight in on a p. dog's shoulder, if I hit him in the front of the rib cage, then I know that the wind is blowing my bullet about 2-3" off, then I can click in more windage in the scope. With low power scopes and no muzzle break, no way in the world you could ever consider analyzing your shots with this amount of certanty.
I eventually ordered McMillen Hunter benchrest stocks empty in the front and rear. I filled them full of lead wool and casting resin. Then after a firing 2000 rounds on a p. dog town over two weeks, it was obvious that a muzzle break was in order to see the hits the way I described above.
After installing the muzzle break, I could tell when I was attempting to shoot the top of a p. dogs head off at 300 yards, whether or not I was shooting an inch left or right or how much over the top of his head I was shooting. I use a tight hold on my rifle, also.
This kind of precision shooting may be of no interest to you, depending on your shooting discipline. Just seeing dirt fly when I pull the trigger on a miss is very frstrating. Shooting center of mass is boring to me, and certainly does not help you when you are trying to extend the range of your rig.