I took my Spike's upper to the appleseed project this weekend. it comes with a YHM rail on it. this was the first time I have ever used it with a sling and it was mounted to the bottom of the rail.

well I was laying prone and really trying to get that sling nice and tight. when I tightened it up the entire rail rotated! the rail is screwed onto the barrel nut and has anti-rotating pins on it. so that mean the entire barrel nut started to back off. when I got home I took out the anti rotating pins and removed the HG. the barrel nut is snug but not 50-80lbs like I have found it's supposed to be. but the thing is there is no way I would be able to turn the nut so that it lines up with the next gas tube notch.

so what do I do? I am afraid of turning the barrel nut and trying to force it to the next gas tube notch. I am sure I can get that wrench torqued down to 80lbs but doubt it will make it to the next hole with out shattering that barrel nut.

Should I use loc-tite on it? will that help or bad idea?

opinions?

No loc-tite on the BN.  You are supposed to use grease.

IMO the railed HG slipped.  Use a tad of loc-tite on that.

Double check the BN and I am guessing you'll find it is still tight.  No way a sling should pull a BN loose.

IIRC the Ft lbs on a BN should be around 40 lbs.  Again - I could be wrong, but think 80 lbs is way too much!

according to the sticky, it's supposed to be between 30-80.

the HG didn't slip, it can't, it has anti-rotate pins in it.  the only way for the HG to move is if the BN also moves.

The nut shouldn't be able to rotate much, given that the gas tube goes straight through it.  That said, you certainly want it tighter than that.

Try tightening it and backing it off a few times with some grease on the threads.  Sometimes that'll loosen things up enough to get it to the next gas tube hole.  Worst-case, some people have lapped the forward face of the receiver a tiny bit to let the nut snug up further, but that shouldn't be necessary.