Originally Posted by
Fox
Well with a proper big game bullet you can expect an expansion of approximately 2x, so your 0.243 bullet would end up being about 0.486 on exit, if you did not hit a rib, blow out a bone, etc. The 30-30 is going to give you an exit about 0.616 on exit, tougher for fat to fill up the entrance and exit hole. This is one reason I was told, by a very experienced black bear guide, so use a 30 cal for bear, not that smaller would not kill the bear but a fatty bear in the fall would fill up the exit hole and you would have no blood trail. The same could be said for a fatty deer, not plugged, but less blood than a larger hole.
All those people who claim the bullet left a "hole you could put your fist in to" either had a catastrophic bullet failure, with explosive expansion, or you hit bone and blew out the bone, which is not something that can be considered as a normal occurrence.