Since AK platforms are considered a bit shorter range than the AR platform, why not get it in the real AK caliber, 7.62x39?
While more expensive than 7.62 now (the Russian stuff), .223 would be easier to access/come across later.
The 7.62x39 is what MAKES the AK a shorter range gun.
Of course, crappy barrels, flexible sheetmetal recievers and a feed system that is not kind to maintaining concentricity of the round during loading also contribute.