if you want knock down power go with a 1 ounce rifled slug Ive seen deer that were shot in the arse and dropped on the spot, guess they died from shock of the impact. knock down power for a whitetail c'mon its not a 1000 lb grizzly........ I been using a 308 win for deer for the past 10 years and never had to put more then 1 shot in any deer I ever killed, ive even killed a few beyond the 250 yard mark, just put that bullet through its lungs its gonna go down, half of the hunt is tracking the animal anyway, they wouldnt call it hunting for nothing. a few of my deer never ran any further then 100 yards had most of them never run any further then 25 yards and had one drop dead in its tracks i have only had one deer I had to track further then 200 yards only because it was a bad quartering shot the bullet only struck its hind left leg shattered its femer she bled out pretty good through an artery gave a good steady blood trail all the way to her. but other then that one Ive been extremely successfull with quick kills. You dont need a shoulder mounted howitzer to kill a deer. this is the most rediculous post i have read in a long time. clean kills for a deer is based on 2 things #1 shot placement #2 a good expanding bullet. If you cant do it with a reasonable whitetail caliber and feel you need a cannon to kill a whitetail chances are you are just weekender and probabaly not the best shot anyway trying to use knock down power to make up for your poor shot... remember theres other hunters in the woods counting on you to be a responsible person with your firearm. Honestly people like that have no business in the woods hunting deer with more gun then thats needed. c'mon broey1 you say you work in a gun shop you have to have more sense then that, makes me almost feel like you have no business selling guns.