by Hoot » Sat Jan 07, 2017 12:25 pm
I have both of those penetrant components. When I run out of Kroil, I'll give them a try.
There seems to be some confusion of terms.
The barrel nut holds the barrel to the receiver. It is often threaded to receive a handguard.
I have seen handguards that were threaded on one end to also serve as the barrel nut. Kind of a 2-in-1. I actually have one.
Bushmaster uses a small threaded on the inside, knurled on the outside, lock ring that you screw on before the handguard.
The lock ring allows you to index the sling stud in the proper position and then lock the handguard in place, like a jam nut.
Unfortunately, the term "jam nut" can be self prophesying. If you do not break the jam of the lock ring against the handguard,
you could damage the threads on the barrel nut that both of them are threaded onto. You could also cause the barrel nut to
rotate and kink the gas tube. Removing the barrel nut itself is a job for a barrel nut wrench only. Anything else is inviting
disappointing results. Some factory gorillas totally disregard the barrel nut torque spec when trying to get the gas tube holes
to align that last little bit of rotation. I had a Rock River upper once that was like that once. My entire 265 lbs of body weight
would not budge it. Wound up having to cut the nut transversely just short of the threads and pop it with a cold chisel. Had
to do that once with a muzzle brake that an inattentive owner allowed to rust in place. Very nerve wracking. Different story.
I suspect that depending upon who tightened the Bushmaster handguard and lock ring at the factory, it could be real easy to
break free or a real PITA. I must have gotten lucky on mine.
Hoot
In Theory, there is no difference between theory and practice. In Practice, there is.