dimbulb
that's just silly. There's a dramatic diff in power between a .22LR and .223 - huge diff.

LOL, indeed.

.223 will work, with caveats expressed by many here - the main one being, under expert guidance (that puts me out of the running). Broadside through ribs into heart/lungs, with hunting bullet? Dead deer (though may run a bit, just as with anything else). I think it's a bit light, when there are so many better choices, but it would do. .243 is a lot more bullet (but still light, IMHO). It the kid is a deadeye with discipline to pass up on less-than-ideal angles, it would do (again, that puts me out of the running)

I've a friend in GA whose daughter used a .223 NEF single-shot. She got several deer... then nailed a very large (around 180lbs) buck. Great shot, to the shoulder. They spent half the day tracking that deer - it laid down several times - finally shotgunned it. Point is - it was great shot placement for a 30-30 or bigger, but not a .223. She's moving up in to a bigger gun (I voted 30-30)

I personally would look to a heavier bullet. 243 is a lot more than .223, despite what some internet dimbulbs will tell you. It won't kick all that much, and will have all the range a youngster can use.

still... I vote 30-30. sufficiency, and light kicking in 150gr.

IMHO, of course...