What I've noticed is not so much what you hit them with, but where you hit them. I killed deer with 3 different rifles last year. A .243, a .30-30, and a .44 mag. All lung shot, all ran a moderate distance.
I killed a deer at the end of the 2009 season at a lasered 236 yards with a .30-30, the 170 grain Hornady went through both lungs, deer ran about 20 or so yards and fell over.
I've had two "went down so fast they disappeared" kills. One with a .300 WinMag at 40 yards, one with a .30-30 at the same distance. Both CNS shots.
Anyway, those are my experiences. The .30-30 is a reliable killer.
