Not much. It has more punch, but between the 6.5 and the 6.8, the 6.5 seems to garner more praise.
Hehehe...I'm gonna have to learn more about guns.
I used to have a 5.56 AR, but sold it when I got discharged.
I never have trusted the gas system/bolt-carrier/bolt arrangement in such a light-powered round.
If the heavier loads are more reliable (or if someone would just put a damned buffer rod in the gas system) I'd be pleased to get an AR-type rifle: The lower receiver is simply brilliant.
http://www.bushmaster.com/shopping/lowers/
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