“...you don’t aim for the brain...”
If you’re using a shotgun and they are going to be that close, then aim for the front legs which will include the muzzle. At that close a range you would have to be lucky to kill them but if you can inflict pain and surprise, you might scare them to run. And blinding them or knocking them down momentarily by taking the legs out will give you a chance to withdraw backing away. It is a shotgun so do your best to cover the animal with projectiles.
wy69
Have you ever shot a bear with a shot gun.
I have shoot to kill.
Shooting at the legs on purpose is just plain stupide.
Aim to drive your projectile down through the head into the neck and chest.