you really have zero combat experience against people with AKs that want to kill you. Your fantasy world and reality are very far apart.with AK'S, cause they "think' that the harder they yank on the trigger, the more they "hump" their shoulders into the butt, the faster the bullet goes. So much for any "need" to fire at ranges greater than the 700 yds offered by a 24" 223 sniper rifle, using VLD match bullets. Your only concerns are if they have the belt feds, grenade launchers, mortars, and coordinated discipline,radios, etc, to outflank you, call in help, etc. That wont be the case if shtf, and by far most of the populace of the US is JUST as ignorant about guns, and many of them "think" that an AK is THE way to go. It's SO reliable, you know. It will ALWAYS fire, until u run out of ammo, TRYING to hit a head that's bobbing around cover,or a dodging torso, at 300m.
Also, a 24" AR is not your shorty. Your need for special ammo is laughable.
If I was "stuck" with an AK, I would not be under gunned, as it would be comparable to your shorty AR, and is also very suppressible.
You should compare the .300 Blackout to the 7.62x39 some time...
but that would take effort on your part.