Fellas - I told myself a long time ago I wasn't going to talk about this but I hafta put somethin' to bed here. I served 30 mo in Vietnam/S.E. Asia, and a some additional time in South America. I used the M16 in combat. I also used a FAL in 7.62, numerous AK-47s, Sten Guns, Swedish K's, S&W76s, the M1, the M14 and numerous pistols. But, as to the effectiveness of the 223 - it works.
The AK-7.62x39 is better for close in fighting and yes, if they use hp ammo it will make a mess of whoever it hits. The same is true for the 223 - if it is ball ammo it is liable to penetrate t&t with little damage, but if it hits bone it will provide excellent results. If we used soft points of hps in our M16s, it would be an entirely different story. If you hit a bone or hard muscle with the 223 ball, the effect is noticeable immediatley. I certainly agree with j two dogs on this.
I actually have few qualms with the 223 as I know it works but in combat it is a real difficult job to try and make your rounds count under stress, and one problem with the M16 is that even a 30 rnd mag doesn't last long if you are just throwing them out there.
One night we went out trail watching with 16s and night scopes and hit the jackpot, so to speak. Two of us made an incredible number of shots and each counted. Charlie was throwing ammo around to try and flush us out but was getting nowhere and we were hitting him everytime we pulled the trigger and everytime we did that it took only one shot, center of the chest.
I can tell you that a 223 ball round with the point flattened is a much better killer than it is otherwise. Maybe if we just forgot about the Hague or Geneva Conventions our little 223 round would become more effective. Mikey.