I am not a believer of worrying about extra weight in a potentially life and death situation. True bear attacks like sharks are rare, but when one occurs it usually does not come to a happy ending. I certainly will not depend on a spray container in a FTF encounter.
Since you were asking about ammo, you can't do much better in a 460 round. It is reasonably priced, available and I can't imagine a bear walking away from a well placed shot. I'm 6'5" and about 300 lbs, and I have shot a lot of different ammo. I admit I wouldn't want to shoot a match with S&W 460, but in a critical situation I wouldn't have a problem. I would rather go down with a firearm even if I miss than bear spray.
Developed as a load to protect hunters while hunting or traveling in bear country, this American made ammunition is sure to keep you safe with its...
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