From all of the tests I have read, .223 is perfect for deer up to around 200 yards but they recommend 150 yards to be safe. I wont usually take a shot unless I am within 100 yards with a 3030 so I shouldn't have a problem with my new .223 AR.
Using 62 gr. 223 Fusion ammo, under 100 yards in the vitals area will drop any Michigan whitetail. Ive seen it done many many times...most dont run far. Plenty enough caliber