I am sure someone can can have more input than me but, it is very small, you will have to hit them good. Maybe lungs, they will run off but nothing can live with a hole in its heart or lungs. I have skinned several that have had 22s in them from bad hits, neck, shoulder, hips. If had been hit with a larger cal. it would have been dead. To me any cal. is good if it will kill one of those pests. You will never know unless you try.