I finished off a wounded Parrie hiding in the rushes by holding the muzzle of the 12G about 5cm from its head. It worked, but had a nice white welt from the trigger guard across my finger too.
A 2nd shot to the head is the best option. I tried an air pistol for finishing off possums but it was a waste of time. If I have to euthanise a larger animal (e.g a cow) I always cut the throat when they drop - I don't want them getting up again.
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