In judging how much a bear could do after it was shot the only experience I have had is shooting deer.  I have shot several deer where on dressing them out I inspected the heart to find a 12 gauge slug went through the heart.  Every time I got a clean heart shot not hitting any bones other than ribs the deer does not die for a while.  I have had them run over 100 yds. before collapsing. I have had them walk over to a grassy area and lay down as if nothing was wrong.  The maximum time they live is maybe 5 minutes.  If they are running they will last less than 2 minutes. A bear could do a lot of damage in 2 minutes.