A pistol, in my opinion, is a close up, secondary defensive weapon.

With no bear experience, I think a shotgun slug with the correct disabling placement (ie: a shoulder) first, would be the most effective. A head shot to a bear seems to usually only ticks him off unless it enters through an opening (ie: ears, nose, mouth, or eye).

It's a shame Stu has crossed the bar. He had the most 10mm experience of anyone I knew or know.