I have a similar problem at our lease in North Florida, I have killed 2 with turkey loads and a 12gauge with xx-full choke. One with a longbeard XR 3" #6 and one with the older Remington duplex 3" 4x6. Both of them under 20 yards, both of them headshots and both of them stone dead as any of the other truckloads that I've killed with rifles. I would not hesitate to shoot another one with a turkey load, pretty easy to get within 20yards of them on our property.