The Stoner AR is like the Browning 1911, there are never 2 quite the same.
All I know is there was a version of the AR designed specifically for use on the Bradley IFV...that might be the XM177. I think it was Shek who said that was a piece of junk. Not sure if it was Shek, but definitely someone on this board had worked with the XM177 and the Bradley.
By the way, next year is the 100th anniversary of the Browning 1911 design.