I tried with my Saiga conversion.
Couple of problems. Finding reloadable brass is a real PITA. Once you do collect a couple hundred and reload them, the semiauto's chuck the brass into next week and the Easter egg hunt begins.
Then there's the bullet fit issue. AK pattern guns use a 311 bullet. 308 can be used but accuracy is so-so.
I sold my Saiga and picked up an AR due to the reloading issue. I didn't want to be reliant on the whims of ammo manufacturer's supply chains, especially foreign sources. 223 is abundant and easily scrounged. I have a 5-gallon bucket of the stuff.
I still have a CZ Carbine in x39 and use cast lead in it.