A friend of mines daughter uses a 223, and has yet to not take a deer (buck) for the last 3 years. I also know of an a-hole that has shot deer with a 17 cal., i say a-hole because its against the law in Okla..The .22 cal. is legal, but shes a little bigger now an ready for a 243, we think. My own daughter is thinking of deer hunting (and for a 14 year old she is a very tiny girl) and the 223 may get passed around, if so there will not be ant varmint bullets being shot, or fmjs. The legal weight here is 55gr, heavier is better.