A Remington 870 12 gauge would be my choice. I have several and a couple of them would be excellent for bears. One is a Home Defense model with an extended magazine - it would be fine with Foster slugs. Another has a rifled barrel with a 1-4x scope on a cantilever mount - it shoots sabot slugs with superb accuracy. I took a running whitetail 10 pt. buck at about 125 yards with the rifled barrel 870. Iron sights might be better for bear defense, and I would prefer the rifled barrel.