Re: Will a 5.45x39mm Mag hold .223 shells?
Hoser, this one of those" If you have to ask, you should not be doing it" kinda questions!
I recently observed a fellow putting 7mm remington (.284 Rem) cartridges, into a rifle later determined to be a 7 Mag. His assumption was, that if the rifle would handle the 7mm Mag loads, the 7mm Rem would be a great understudy, for practice.
Practice ended early, with a broken stock, bottom metal blown out on the ground, and a stuck bolt.
Anything that shoots the 5.45 X39 round will handle the .223/ 5.56 Nato ammo, but first the barrel will have to come off, and be re-chambered for the cheaper round, and the gas system adjusted, to reliably function.
The mags themselves may have to be modified to feed, reliably, as the .223 case body diameter is some smaller than the AK 74 round.
In a word, my advise is, "Don't", and certainly do not attempt to fire .223 ammo, in a 5.45 X 39 chamber; fingers and eyes just don't regrow!
Don't start no s**t and there won't be none, Terry