The shot might be a little low depending on your shot angle. Brain shots are the way to go with a heavy dome pellet perpendicular to the skull. Almost 100% of the time even with a perfect brain shot they will do the death dance for over 1 min. at times. I've seen 45 sec to 1.5 mins. You can tell if the death dance is a good or bad shot by what is wiggling. If front legs don't trash around only the rear legs then it is a good fatal shot. Also they drop motionless for about 1 sec before the nerves go nuts and that start to dance. I've seen blood within less than 2 sec of a good shot come pouring out of the nose! Clearly fatal but yet still danced for over 1 min.
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