It is not the "Big bores" that stop deer faster, it is the cartridges with more velocity. A few years ago I used a 30-30 to hunt with for the first time. I have owned plenty over the years, I just never hunted with one. It was a classic double lung shot with 170Gr Rem Corlokt (I swear by Corlokts). It took off throwing blood and headed for a deep ravine. I was really getting worried following it. It wound around and distance is hard to judge, but it seemed a heck of a lot farther than 50 yards to me. I honestly believe that was the farthest I ever followed a deer that was hit right. I have used what I call "Medium" rounds(.260, 7x57,6.5x55) and with lung hits there are pieces of lung laying where the deer was hit. I also use cartridges like the 7.62x39(With Corlokts), but usually head, neck, or shoulder shoot them if I have to anchor them on the spot. Nothing wrong with the 30-30, but as others stated, shot placement is everything for a short run. I realized it was a low pressure round, I just was not thinking at the time.