As said above the 7.62X39 is in the same performance catagory as the good old .30-30Win. Sounds like a 7.62X54R to me. Don't know much about those, but if I was looking for a back-up gun for dangerous game I would want something with a little more power like a .338.

Just a thought though, what about the surplus 7.62X39 ammo that had a steel core? For close range on bear, I would think that would be quite effective if shot placement was good.