If it is about performance evaluation, shouldn’t you be comparing the shorty AR you tout? And 600 yds isn’t really that far, if you’re talking about sniping.u r fos. 80 gr vld's still have 500+ ft lbs
at 600 yds, fired from a 24" barrel. That's the same level of power as the much ballyhooed 4" 357 revolver has at 10 ft, using 125 gr jhp's. You dont NEED to knock the man on his ass at such ranges. All you have to do is ruin his ability to hurt you, and the 223 does that just fine. You powermad assholes are such twits about such things. Nobody HAS to hunt at ALL, much less take game at such ranges. Nobody has to "snipe" at such ranges. Like little KIDS, WANTING-to is the samething to you as "needing to". Well, there IS a diff, and the 223 DOES do many things that the 308 CAN'T do, like use a .22 unit, used the GI rifle rd, be usable one handed, conceal in an attache case, conceal on your person, be handy with a can attached, all of which are of considerable value NOW, and may well be priceless advantages if shtf.
No, dumb ass, it's NOT "apples to oranges". It's about PERFORMANCE evaluation, something which you are UTTERLY uncapable of doing.
please define shtf, because your list of requirements seems very specific and unrealistic.