The .223 stinks threads are always interesting. Bottom line is that it doesn't have the horsepower to close the deal on a marginal shot or even a good shot like the one I mentioned in my original response. And, if we are all honest, we will take the marginal shot from time to time. The doe I mentioned in my first post would have been stone dead with something that had the penetration to travel through her. A Barnes bullet and the patience to exactly place the shot aren't always possible. I haven't found a Barnes that shoots good in my rifles with factory ammunition. 77 grain Sierra's out of a 20" barrel have given me the highest success rate on shooting deer with permits.