I know of Armalite, and DPMS that produce 308 AR rifles and parts. Bushmaster has discontinued their 308 product line.
Are there any others? I'm thinking of getting an MGI quick change upper receiver, a barrel, and a 308 lower receiver to build a 308 AR rifle.
a 223 upper will not fit a 308 lower, even if its a CD upper
223 uppers pins are too close toghether to work on the 308 lower.
They are two diffrent animals size wise, and also very from manufacture to manufacture when dealing with the 308 version,
MGI may be building a QD upper set up for the ar10, not sure if this was the version that you are refering too, or when it may be availible