I and those I've hunted with have used 223's on several deer and antelope. My brother killed two does with one shot using 60 gr Partitions. The bonded-core bullets have been used several times, along with 68 and 75gr Hornady BTHP, and a few Hornady 55gr PSP. All have exited the chest or neck, regardless of shot angle, though most have been broadside, regardless of the amount of bone hit. Distances have been from about 60 to a bit over 200 yds. Though I'd not carry the 55's when hunting trophy deer, my nephew shot a huge whitetail through both shoulders at about 200 yds using them. The heavier bullets have all gone through at least one shoulder, and the Hornady BTHP have both been shot through both shoulders of deer 180-220 lbs. The Partitions and bonded bullets are surprisingly hard to stop, since both have been used on quartering shots and have still exited. The two does with one shot and a Partition were broadside. The 2nd doe was hit through the low shoulder after no bone was hit on a ribs shot of first doe. We had several doe tags, by the way.
So I have no fears about using 223's on medium game animals at standard ranges. The wound channels aren't ever huge, but that has been irrelevant. The animals have never gone very far, no more than a handful of steps. The 223's are easy to shoot well, even for kids, which likely also contributes to their effectiveness, because all bullets have been placed well.
