Now that's not a fair compairson at all, For what it's worth I misread the original post and missed the "brown bear" part, so no I would not take a 308 after BIG BEARS how ever an arrow tipped with a cut on impact broad head will out penitrate a bullet every time unless there are big bones in the way but I wouldn't take a bow bear hunting anyway well to be honest I don't ever see me hunting bears just not my cup of tea I'll let others control the population.