One of my close friends shot a grizzly bear through the head from 12 paces as it charged him. Folded it right up dead as could be. His tool of choice for the job? A 2” S&W 296 44sp with 250gr Keith bullets. I doubt that they’re going much over 800fps.
I’ll never forget what he told me regarding the experience. “I knew I’d have to head shoot him to have a chance. When he charged his paws looked as big as frying pans and his head as big as a tennis ball!”
