From what I have gathered so far, 7.62x39mm's supposedly will penetrate people and obstacles like a knife through hot butter, whereas the .223 won't. Basically, I'm worried about overpenetration for in-house fighting in non-military environments. I don't want to shoot someone, have the bullet penetrate the person, come out the other side, go through a dry wall, and hit someone else. So, my question is, is the .223 preferable over the 7.62 in terms of overpenetration? Has anyone had experience or tested .223's on dry walls? If so, did they overpenetrate as well? Any help would be greatly appreciated. Thank you.