Trigger, I've enjoyed the replies you got on what could have easily degenerated to a ****ing contest. Several of the guys who use or endorse the use of a .223 (with caveats) have to be listened to. But I still don't recommend it for deer. I have killed several deer and have seen deer killed by others that had been wounded. Some were fresh wounds, some were old enough to be haired over, and weren't found until the deer were skinned and dressed. Recovered bullets and fragments were nearly all small cal, appearently .22 cal, (jacket bases, usually) with a couple of .243's, and one .30 carbine ! I've never seen or recovered a 7mm, .30 cal, .338, or .45 cal fragment from a previously wounded deer. I also have only killed one deer that had an old exit wound anywhere. That exception was a .243 jacket base with a little lead left in it that was lodged in the inside of a hind leg after passing low through the paunch. All 3 holes were partly haired over ! That deer also had a fresh superficial wound low on the front of his neck.
I will concede that if it was the only rifle I had, I would use it, but not over 200 yds, and only then if I had a head shot on a deer that was standing still.
Another big factor in my preference for larger calibers was a case of terrible shot placement on 2 does 10 yrs apart. Not my finest hour. I gut shot a doe at 285 yds with a .300 H&H (190 gr Smkhp). It knocked her down so hard that she died before she was able to get up. I watched her die. That sucks. Did it again 10 yrs later with a 7-08 at 140 yds. She didn't go down, stood still for a minute, then walked about 20 yds and fell over. That sucks too, (it ruined both hunts for me) but in both cases, neither deer made it out of my sight. With a .223, I doubt I would ever have found either one.
My go-to gun is a .30 x .378, backup is a 7-08 or a .280 Rem. All can shoot better than I can, but the .30-by is an open can of whup-***. BTW,I do have a very fine AR-15 that I carry with me in case I get a chance to hose some pigs. And I'm not a bit picky about the distance on them.
I regret getting so long-winded, but to sum up, if you have a choice, I still don't recommend limiting your hunting with a caliber that has so many practical and ethical limitations.
A comment for Dave King's bell curve. "That's funny, I don't care who you are". Just once though, I'd like to be in statistical control on ANY bell curve.
Whatever you decide, good hunting, Tom
