I've seen one deer killed with 00 buck. One shot from about 20 yards dropped it right there. As I remember all pellets hit in ribs and exited the far side. I don't think any human is going to walk away from it. When I took my hunters safety course the instructor showed us pictures of people who were killed in hunting accidents. One that sticks in my head showed a guy who took a load of buckshot to the face from close range. His head looked like a pumpkin that had been smashed on the road. Obviously his skull was completely shattered and the back of his head was gone.
