There are a few things about the 6.8 that makes it a little different from a 5.56. First there is .010 difference between the the minimum and maximum allowable chamber sizes . If the barrel bolt combo are just under the no-go and the factory ammo is .004 under the minimum you can have .012-.0013" of slop which hurts accuracy. Sizing the brass(shoulder location) .002-.004 under the actual chamber size helps accuracy.
SSA brass is .415" dia at the base, Hornady and most of the others are .417-.418, the chamber is .422 minimum, .424 max. That slop doesn't help accuracy either. Hornady 110gr HPBT seem to be more accurate than most factory ammo.
Muzzle rise with the 6.8 is a little worse than a 5.56 especially with a shorter lighter barrel, a sling or some front end control can help.
The lock time on an AR is slower than a Rem 700. Many guys have a hard time when they first start shooting ARs until they use proper trigger follow-through. A good non mil spec trigger makes a huge improvement.
Last edited by constructor; 04/23/16.
