Let's dispense with the Caliber Wars here. That is a realy nasty snake. A Cottonmouth. A Water Moccasin. The only appropriate weapon is a 12 Gauge with No. 8 shot. I have dispatched several with my trusty 12 GA several times, and firmly believe anything less than 12 GA is criminal. A 10 GA would be better. Maybe even a General Electric GAU-8/A.
Do you understand me, pilgrim?
Poor fella. Undergunned and clumsy to boot. Good spirit though. Darn lucky he didn't get bitten then eaten though.