AP BAR Nut

[hg8057]

I recently received an AP BAR Nut (w/shims) to mount a barrel to a standard forged upper. There weren't any instructions included. I've got a vine out to AP and haven't heard back yet. Can someone help me out with install instructions? I'll include a pic for clarity.

[UWone77]

Same as a Seekins MCSR/BAR Rail install.

You'll need a 2 pin armorers wrench.

Handtighten, and then torque to 35-50ft-lbs. Use the shims as needed to time the barrel nut to the screw holes.

[hg8057]

Pretty straightforward. So, in theory, if I'm lucky I could torque it down without having to use any shims. Thanks a bunch.

[hg8057]

...I've got a vine out to AP...

I sure didn't realize vine is has a newer literal meaning. Let's just substitute "message".

[hg8057]

Handtighten, and then torque to 35-50ft-lbs. Use the shims as needed to time the barrel nut to the screw holes.

I finally heard back from AP. Their specs seem way too high. My favorite part was, "I believe our assembly team downstairs..." Uh, call down there and find out. Here's what they told me:

" We actually don't have any literature at this time for the install of the BAR barrel nut, but we are working on getting some instructional videos posted to the website to assist customers with their builds for these specific barrel nuts we offer. I can try and help you out as best I can, as I know these probably won't be available until later this year.


First, you definitely want to make sure all threaded areas are properly greased up to avoid any seizing up, which I'm sure you're aware of. Then you want to try and mount the barrel nut without using the shims to see if it will align correctly for the gas tube to fit through. If it does not align, add 1 shim at a time as needed to get that proper alignment. I believe our assembly team downstairs torques to the specified torque of 55ft lbs, then backs off, and then repeats this process 2 more times. You can torque up to 75ft lbs without over torquing the barrel nut in case a little further adjustment is needed. "

[UWone77]

I think I got the specs from Seekins. For the most part, I've had no issues with any of my AP Barrel nuts torqued at 35-50 ft-lbs.

[hg8057]

I think I got the specs from Seekins. For the most part, I've had no issues with any of my AP Barrel nuts torqued at 35-50 ft-lbs.

I'm gonna go with your torque specs. You know what you're doing, the guy from AP didn't seem too sure. Now only if I could get my barrel back from having it dimpled for a set screw gas block...

[SINNER]

Grease the barrel extension and both male and female threads lightly.

Hand tighten the barrel nut to see where the gas tube hole falls. You want the gas tube hole to fall between 10-11 o'clock hand tight.

Set your torque wrench to 40 ft. Lbs.

With one hand slowly and smoothly start applying torque to the barrel nut while with the other hand push the gas tube into the receiver.

I find that right around 40 ft lbs the gas tube with slide into position and that's it. I will go as high as 60-65 ft lbs to get the holes aligned correctly. On forged uppers I often find one shim is the magic number. So often that now I usually start with one from the beginning.

[hg8057]

UWone77 & Sinner:

Thanks a bunch. I knew I could get the right info here.

[hg8057]

UWone77 & Sinner:

Thanks a bunch. I knew I could get the right info here.

Finally got it done today. Came in at just a smidge over 40 ft/lbs with one shim.

Thanks again.

[UWone77]

Finally got it done today. Came in at just a smidge over 40 ft/lbs with one shim.

Thanks again.

Where are the pics of the gun?!

[hg8057]

Where are the pics of the gun?!

Well, I wasn't quite accurate. The upper is done. The lower lacks only a trigger and a different mag release button. Waffling between the Geissele G2S and the RRA Varmint 2 Stage.