You can empty 10 handgun mags into a bear and its going to have little effect. You should basically just start running unless you have a .44 magnum or something better.

In Canada, I see the Marlin 1895GS "Guide gun" in 45-70 Govt is a popular choice for bear defense by people who work in the bushes. The economical route is to go with a short barrelled shotgun (14 inch or less) loaded with slugs. That usually does the job.

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"Conservatives are not necessarily stupid, but most stupid people are conservatives." — John Stuart Mill