Arguing about caliber is silly. It's exactly the same in the self-defense world. Shot placement is more important than caliber.

At 120 yards the OP did the right thing by shooting the thoracic cavity. Lots of good targets in there. Also, hitting a little high and getting the heart is reasonable. The bullet will ricochet off bone or just tumble when it hits resistance. Not to mention fragmentation.

Again, any round that's capable of penetrating the skin, is good enough to take the intended animal.

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