According to the guys at Sierra, the 80gr MK bullet does a poor job on varmints due to its thick jacket.
Assuming that you don't "dust" the A-Max in your fast twist barrel, they are a very deadly varmint bullet at any range.
This groundhog was killed with a single shot @ 840yds. The bullets do not exit, although sometimes frags blow through. [img]/ubbthreads/images/graemlins/grin.gif[/img]