Most any bullet, is as lethal as the next, if you use proper placement, which is paramount using any round, but more important when using what some might say marginal rounds for a job.
Whatever bullet is used, in any round, should be placed to maximize it's design. Soft bullets work best on soft tissue like lungs, harder bullets do better on bone.
I have faves, but I have used 'marginal bullets' - IN marginal rounds, with deadly effect on whitetails. One example, a 70 TNT in a 243, and also in 6mmBR. NOT my chosen HUNTING bullet for game, but in those situations it was what the rifle was sighted in for, so I used accordingly. The 243 nearly decapitated a WT at 50 paces........and a 6BR using said bullet destroyed both lungs at about 200 yds......so yes one was DRT and the other went 60 yds......Both DEAD.
Any 'hunting bullet' made for 223s, avoiding varmint and target bullets, should work fine - when using good placement. I would not sweat bullet choice, but instead be very sure of proper placement which is rather easy to say 250 yds and under in any decent rifle, with good trigger and sights. Lungs on longer shots, MAYBE neck and even head shots on close shots, but not on any trophy deer where you risk messing up a mount, or a last second move causing a wound or miss.........so for ME, I would save neck/head shots for Doe's.
Good hunting folks.
