.177 or .22 for me?

[model 70]

i'm no expert but that sounds like a tall order for coons. a co-worker shot a opposum at about 3' in the head with a .177 pellet rifle. he said he had to shoot it 5 times before it died. what about a .22 short and make sure you there is nothing behind your target. seems like a bolt action .22 rimfire using .22 shorts would be perfect for close up coons....if you don't mind a hole or 2 in your deck