Howdy all,

  My friend and I built up a couple of nice AR carbines this weekend, and ran into a snag.   I have a Shilen .223 Wylde, 20" .936 fluted barrel, that I mated to a Rainier arms billet upper receiver.  Everything went fine....until I tried to put the barrel nut on.  The barrel OD is too large for the ID of the barrel nut.   Out of curiousity, I took an old Yankee hill machine carbine rail with it's proprietary barrel nut, and it fit fine.    So obviously I need a specific type handguard that comes with a proprietary barrell nut with a larger ID to fit.    I am looking for a handguard like the JP unit that is smaller/lighter, and has slots/holes for rails.   When going thru the various sites, there is no info on the ID of their proprietary barrel nuts.

  Any one have any info......and....is there a company that makes a standard type barrel nut.....with a larger OD???    


Thanks much

Pat

I ran into that also with the DPMS SASS barrels in .223   The Spikes/ Seekins BAR and SAR wouldnt fit.   but they would have made me a nut that would have.   or i could have had a machine shop open up the diameter of the nut slightly or profiled the barrel.

Here is a drawing of the mil spec nut.



I would suggest contacting Shilen and asking them which nut they spec for their barrel.




 

After some measuring of the ID of the stock barrel nut, and the YHM barrel nut, it was obvious that there was a .120 difference.  My friend is taking two stock barrel nuts down to a local machine shop to have him open up the ID on a lathe.is  Cost will be about $40, which is significantly cheaper than purchasing a $330 PRI forend, or having the barrel turned down.

So...alas...I guess I can wait while the loctite "green" sets on the barrel/receiver.

Thanks for the input...and glad I'm not the only that has run across this issue

Pat

I've never heard anything like that before. My Krieger barrel was 1 inch in front of the barrel rear shoulder, and took a .936 gas block. I just measured a Mil Spec. Barrel nut. The dia that goes against the rear shoulder is 1.015. Sure as hell should go over a .936 dia barrel. The hole in the barrel nut is .079 larger.
APEX rails will fit over a standard barrel nut. Put the rails anywhere you like. Also look a lot better than the JP ones. Look on Rainiers site. I have 5 sets, love the feal.

Why are you going to use Loctite in this area?  I can guarantee that you will regret it later when you try to remove the nut/barrel the next time.

Oh hell yes, especially the green stuff. And if you were going to use any Loctite, I would surely want that barrel tightened down and torqued to proper specs when it sets up. That green stuff is for bearing seats and press fits. Not meant to be removed. Removal will take a lot of heat!