Rock River nm sling swivel

[TomMPR]

Hello all, i'm trying to assemble my new rock river national match flat top.  I can't figure out how to put the nut on the sling stud that goes through the botom rail of the handguard and tighten it.  Just not much room to work right there. I feel like i'm missing something. If it was that difficult to install then it makes sense that rock river would do it when they build the rifle. Seems like anybody with a use for a nm rifle would need the sling swivel on there. Would appreciate help if anyone has experience with this setup. Thanks

[Mark Davis]

I pulled rock river NM rifle out of the safe after reading your question.
No help here, mine lacks a bottom rail, the front sling swivel is riveted to two tabs that are welded to the free float tube.
Can you post a pic of your parts?
Is there a chance that some heavy grease will make you nut stick in place long enough to thread it?

[TheMenace]

Is it an M-lok forend? If so, the nut (attached to the screw) will slip into the slot and with tension away from the rail will rotate and lock as you tighten the screw. There are YouTube videos showing the method.

[TomMPR]

I can't figure out how to post a picture. Rock river's nm sling swivel goes through the frontmost hole that mounts the bottom section of rail to the handguard. It doesn't have a t-nut like an m-lok set up. Countersunk hole in rail, threaded hole in handguard. The swivel came with a fiber washer, and a nut that has grooves around the circumference like it's only supposed to be hand tightened. I'm starting to wonder if the nut is somehow supposed to act as a jam nut just to keep the swivel indexed?

[Tennessee Beast]

Like the one here?

https://www.impactguns.com/Semi-Automatic-Rifles/Rock-River-LAR-15-NM-A4-CMP-Rifle-5-56-20-Barrel-12-5-TRO-Rail-20-Rd-Mag-RRA-AR1289-AR1289/

[TomMPR]

Yep, that's it

[TheMenace]

I have that rifle. My swivel attaches at a tapped hole in the handguard. The washer and nut are "jammed" between the swivel and the forend.

[TomMPR]

I wondered if that was it. Is the washer between the nut and swivel, or between the nut and handguard?

[TheMenace]

The washer is between the nut and swivel. Although, it would make more sense to have the washer between the nut and handguard. Mine was assembled at the factory that way.
Try it and see which one results in a sturdy mount.  I've been happy with my RR MN rifle. Good luck.
In Liberty!
Dennis