My first question is, do you want to shoot AND eat them? Or just eradicate them? If you want to retrieve them, take the 30-06. I’ve shot them in Texas, they are tough animals. I used a 6.5 CM with Barnes 127LRX. It worked great. I was able to shoot all but one in the spine 2” behind and 2” below the ear, they dropped right there. One was running toward me and I was on the ground. When it got 30’ away I shot him in the center of his chest and he turned and ran 10’ to my left, I shot him again as he passed and he dropped. If you want to find them 100% of the time, I would not use a 5.56. The area I was hunting was thick woods, if they ran very far with no blood trail, you would never find them. I know plenty have been shot with a 5.56 and retrieved, but I would only use one if I could get a head shot or in open fields.