The lower I ordered is stamped multi caliber. Does that mean I can use a .308 upper, or is that just meaning .223/5.56?
Multi just means that you aren't stuck with .223/5.56x45.
Why hasn't anyone tried to use mag blocks and conversion kits in AR10's?Dammit. thought you could throw a .308 upper on a .223/5.56 lower. Boosauce.
Good thing I didn't order that Armalite upper...