I don't have a Varminter, but I do have a "plain jane" Bushmaster A-2 that is very accurate for what it is. I can fairly reasily bust groundhogs out to around 200 yards or farther with Silver Bear 62g HPs. The only thing I've done to mine is a trigger job, and turned the front post down to a finer point.
There's no doubt in my mind that if this rifle wore a scope, it would be capable of some pretty decent groups with tailored handloads.
I can't imagine a heavier Bushmaster, with a better barrel not shooting at least a little better, if not a great deal better than mine.