Have a smith check it out with a bore scope. See if you damaged the mount or any baffles. If you did, I would contact Surefire to see what can be done.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body">You didnt have the lock collar torqued down properly.... The 556 mounts are the same as the 762 mounts minus bore hole ID. </div></div>
^^^^^^
Same thing happened to a friend of mine (honestly, it wasn't me...). Happened on about the 5th shot, amazingly no baffle damage.