Reliable feeding with such would be almost impossible as would extraction. I tried modifying bolt heads and numerous other methods to get 7.62 NATO blanks to feed and extract for a training company I contracted to. Never proved successful.
Besides, having recovered numerous MNs, both rifle and M44 types from Viet Cong I never found them short of 7.62x54R ammunition. Also recovered or destroyed tons of that ammo in their cashes. I doubt there ever was a need to shoot 7.62 NATO in their MNs. They would have used the captured 7.62 NATO in the captured guns, mostly M60s.