Its a good choice for whitetail out to about 150, not much longer. As far as mulies, I dont know. I have never hunted mulies but from what i have heard and seen on tv it seems like they are usually very long shots. Which limits the capabliities of the old round nose 30-30. I mean if you could get in range and place a good shot on a muley it would do the the job. Its basically a short range deer rifle.