Oh, and you're right about the aluminum barrels, they were steel inner barrels with an aluminum outer; just like an AR7 barrel. It was that ruptured barrel incident that bumped the AR10 out of the running for the US service rifle, leaving the FN and M14 to fight it out.
Oh, still remembering details...did yours have a chrome bolt and carrier? Did it have the cocking handle in the carrying handle?
