Converting m16 to .308 or 7.62x51mm

Question

when u convert an m16 or any of its family members from .223 or 5.56x45mm into .308 or 7.62x51mm, do u have to change the lower receiver? because the magazine is bigger for .308 than .223, so in order for a .308 mag to fit, wouldnt u need a different lower receiver?

Answer 1

Yes, the lower receiver also needs to be changed.