Depends on the area you at. Likely hood of cougars/bears I carry my .454 Casull. Likely hood of two legged animals 9mm. The .454 will run off anything just by the noise of the round going off. Sounds like a thunder clap in your hand. 9mm hold 15 rounds and is much lighter. Just about any gun .380 and up will deter any animal. I would not carry anything smaller though. May just upset them.
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