Have both 308 and x39. You can interchange the stocks but since the 308 stocks dont have that welded bridge to hold ak mags, you wont be able to use ak mags. I tried it and the ak mag will insert in 308 stock and will lock in but it is extremely wobbly!!!! Doubt you would be able to cycle any rounds through it. Unless you want to use it as a single shot rifle then yeah you can swap stocks. Hope this helps.