Nails, every deer will react differently. Unless you interrupt nervous center by brain or spinal shot you run the risk of a deer getting up and running. I've blown hearts apart and watched those deer run in upwards of 150 yards before dropping. It doesn't matter what you hit them with. I watched one deer I absolutely NAILED go 130 yards from impact point with the whole top half of the heart and both lungs decimated from a 180 grain SP from a .30-06 at 85 yards. I've also seen deer drop like the hammer of Thor was smashed into their sculls from that same shot from a .243. Sometimes they run, other times they drop. It's mainly why I switched my target to high shoulder when gun hunting. 90% of the time I get spinal interruption and drop the deer in it's tracks. If I miss a bit low, I have still gotten the lungs and if I miss a bit high then it's not a bad injury to the deer and it will heal up quickly for another day. Larger calibers may be a bit more forgiving, but the fact is, proper shot placement should be the main focus no matter what you are shooting. The larger caliber rifles aren't needed for scraggly little old whitetails. Not if you put the bullet where it belongs.