7.5 inch shorty issue

angrysoldier

angrysoldier

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I'm putting together a nea shorty build. Here is the problem. When I tighten the barrel nut and try to put the gas tube into the receiver the ridge on the barrel nut is in the way. Due to how the mating surfaces on the barrel nut interact with the fore end I don't see away around this issue. This is not my fist at build but it's my first with nea parts. Any help will do.





 
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on the left side of pic is a tab that aligns the hand guard with the upper. I cannot torque it more due to the alignment of the tab. Might try the shim idea.
 
angrysoldier said:
on the left side of pic is a tab that aligns the hand guard with the upper. I cannot torque it more due to the alignment of the tab. Might try the shim idea.
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Last NEA forearm I installed I had to SHIM the barrel nut for it to index proper. Finding them were hard, when I talked to Questar they said they never had to order in shims before.

I ended up making mine out of Copper washer. I thought with NEA you install the notch before and twist, than it centers.
 
back off and re-install the nut a couple of times, it will help seating the nut a bit more snug. you can also back of the nut just a hair to line things up, once installed your gas tube will lock the barrel nut in place anyways.
 
If you have a friend with a lathe skim off a small amount and get the alignment perfect.

Or have it surface ground by gunsmith enough to mate perfectly. Very quick and easy job.
 
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angrysoldier said:
on the left side of pic is a tab that aligns the hand guard with the upper. I cannot torque it more due to the alignment of the tab. Might try the shim idea.
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Huh? Tighten the barrel nut so that the gas tube channel in the barrel nut lines up with the hole and then slide on and install the handguard. The tab on the handguard should in no way interfere with the barrel nut installation.
 
The barrel nut is machined to fit the fore end. I wish it was as easy as my Yankee hill machinery's fore end. I will take it to work tomorrow and work on it there at lunch
 
angrysoldier said:
The barrel nut is machined to fit the fore end. I wish it was as easy as my Yankee hill machinery's fore end. I will take it to work tomorrow and work on it there at lunch
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I don't understand why you can't install the barrel nut to allow the gas tube install and then put on the handguard. The handguard can be installed anywhere on the barrel nut and then rotated until that tab hits the upper. For instance, you could slide the handguard on the barrel nut upside down and then rotate 180 degrees clockwise until the tab meets the upper and then tighten the two hex nuts to keep it in place.

I've installed half a dozen NEA handguards. Feel free to pm me if you'd like.
 
Even with a barrel nut wrench it's not lining up. I've high lighted the issue. This is one of the new nea 9 inch fore end with the new barrel nut. Inside the fore end there are Groves that match up with detents on the barrel nut. When tightened to contact with the upper and torqued it is missing aligned. Pics to follow.
 
angrysoldier said:
Even with a barrel nut wrench it's not lining up. I've high lighted the issue. This is one of the new nea 9 inch fore end with the new barrel nut. Inside the fore end there are Groves that match up with detents on the barrel nut. When tightened to contact with the upper and torqued it is missing aligned. Pics to follow.
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You need to shim it. So the gas tube groove aligns ( envolves taking off the barrel nut and slipping a washer over the barrel ) Than reinstalling the barrel nut. You might need to play with the thickness, till it indexes. Than you push the rail on a angle and twist to center it. The forearm doesn't slide in straight and clamps.If you look into the fore arm, you will notice grooves, and area for those tabs on the barrel nut to slip into another groove. Basically centering it.
 
angrysoldier said:
Even with a barrel nut wrench it's not lining up. I've high lighted the issue. This is one of the new nea 9 inch fore end with the new barrel nut. Inside the fore end there are Groves that match up with detents on the barrel nut. When tightened to contact with the upper and torqued it is missing aligned. Pics to follow.
Click to expand...

I think you need to take it to some one with more experience to help you out.

If not, follow these steps:

1) install barrel nut to acceptable tightness with the gas tube groove lined up with the hole in the upper.

2) install your gas block/tube.

3) slide handguard on with the tab just offset from the upper.

4) rotate the hanguard into alignment. It may take a bit of effort and twisting back and forth as these handguards fit tight on the nut.

5) tighten the two clamp bolts. Do not over torque.

From your pic I would back the nut off the little bit and install the gas tube, provided it's still tight enough.
 
Stevo said:
I think you need to take it to some one with more experience to help you out.

If not, follow these steps:

1) install barrel nut to acceptable tightness with the gas tube groove lined up with the hole in the upper.

2) install your gas block/tube.

3) slide handguard on with the tab just offset from the upper.

4) rotate the hanguard into alignment. It may take a bit of effort and twisting back and forth as these handguards fit tight on the nut.

5) tighten the two clamp bolts. Do not over torque.

From your pic I would back the nut off the little bit and install the gas tube, provided it's still tight enough.
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I've been building guns for 20 plus years.this is the first at that has ever given me a problem. I will take it to the shop where I work and get a second opinion. This is my first low budget build and my last.
 
angrysoldier said:
I've been building guns for 20 plus years.this is the first at that has ever given me a problem. I will take it to the shop where I work and get a second opinion. This is my first low budget build and my last.
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Yeah but you never used this system before, so building for 20 + years is useless. Listen to what hes saying. I built AR15s since 2004, and first time I worked with a NEA system, I was confused. What Stevo is saying is 100% correct with this NEA system.

Paying someone for a second opinion, is wasting your time. Also when they tell you the same thing your arguing against people trying to help. Your going to be embarrassed. Amuse us .. Why not just try to back off the nut to get it to align and just try it. If it works than all you need to do is shim so it indexes.

Anyway you put it you need to align the barrel nut for the gas tube to go thru.
 
The barrel nut should be torqued to 30 foot poundish.

If you back up half a slot and you can still get around 25 foot pound. i will call it a day. Otherwise, get a shim off MacMaster Carr.
 
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