Can't get VTAC rail to slide over barrel nut!

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[ARCHIVED THREAD] - Can't get VTAC rail to slide over barrel nut!

Posted: 7/25/2013 4:38:06 PM EDT

First build so please excuse the newb question.

I have a 9" Vtac rail and Armalite basic Ar-15 barrel nut from Primary Arms. Troy states the VTAC rail uses the standard barrel nut so that's correct.

The issue is when I try and slip the rail over the barrel but (uninstalled from the upper) it will not go into the rail. Tried a little CLP to lube it up a tad, but no luck.

How easy should the rail slip over the barrel nut?

Thanks,
Kiel

Posted: 7/25/2013 4:43:23 PM EDT

[#1]

Can you get it over the nut at all? They need to slip over the nut then be aligned.
Here is a video that shows install Around the 28:40 mark
http://www.youtube.com/watch?v=Yd6ydTAdMjw

Ryan

Posted: 7/25/2013 4:46:02 PM EDT

[#2]

No I can't get it over the nut at all. Even with the nut off the upper, I can't get the nut to slide into the rail. It's like the teeth on the nut don't line up with the splines of the rail correctly.

Posted: 7/25/2013 4:50:17 PM EDT

[#3]

It must be the TRX model that needs their nut/wrench

Posted: 7/25/2013 4:54:43 PM EDT

[#4]

Quote History

Quoted:
It must be the TRX model that needs their nut/wrench

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No its says on their site it uses the factory/basic barrel nut.
http://store.troyind.com/Troy_VTAC_BattleRail_Alpha_p/strx-avk-90bt-01.htm
I'm thinking the barrel nut is slightly out of spec. It shouldn't be this hard. Could be user error though

Posted: 7/25/2013 5:12:57 PM EDT

[#5]

Pictures are your friend. Are you canting it when you try to slide it over? Do you have the screws threaded in only a round or so? It's tight but it should go. If it doesn't work try a different brand of barrel nut. I know the core 15 nuts have issues with them.

Posted: 7/25/2013 5:35:59 PM EDT

[#6]

Quote History

Quoted:
Pictures are your friend. Are you canting it when you try to slide it over? Do you have the screws threaded in only a round or so? It's tight but it should go. If it doesn't work try a different brand of barrel nut. I know the core 15 nuts have issues with them.

View Quote

Some times they are difficult to get lined up just right to go on.

Posted: 7/25/2013 6:55:30 PM EDT

[#7]

Quote History

Quoted:
Can you get it over the nut at all? They need to slip over the nut then be aligned.
Here is a video that shows install Around the 28:40 mark
http://www.youtube.com/watch?v=Yd6ydTAdMjw

Ryan

View Quote

Yeah in this video the rail slips right over the teeth on the barrel nut. The guy had a little trouble getting the tabs over the nut correctly but that isn't my problem.

Posted: 7/25/2013 7:15:33 PM EDT

[#8]

Here's a pic. Cant get it any further than this.

Posted: 7/25/2013 7:20:25 PM EDT

[#9]

Quote History

Quoted:
http://www.tacomaworld.com/gallery/data/500/medium/20130725_230803.jpg

Here's a pic. Cant get it any further than this.

View Quote

can you post a pic looking from the barrel nut forward please.

ETA: I have an that same rail in 13" and it was VERY snug on a CMMG nut. I had to put the upper in a vice to slide it on.

Posted: 7/25/2013 7:40:13 PM EDT

[#10]

Quote History

Quoted:

http://www.tacomaworld.com/gallery/data/500/medium/20130725_230803.jpg

Here's a pic. Cant get it any further than this.

View Quote

unless im missing something obvious, but thats the wrong end

edit: is the rail have the same ID from end to end? i have no idea, ive never looked

Posted: 7/25/2013 7:51:48 PM EDT

[#11]

Quote History

Quoted:
unless im missing something obvious, but thats the wrong end
edit: is the rail have the same ID from end to end? i have no idea, ive never looked

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
http://www.tacomaworld.com/gallery/data/500/medium/20130725_230803.jpg

Here's a pic. Cant get it any further than this.

unless im missing something obvious, but thats the wrong end
edit: is the rail have the same ID from end to end? i have no idea, ive never looked

No its the correct end. If you look close enough you can see the tab that stops next to the upper when installed on the right side if the pic. Did try both ends to make sure the rail is out of round. Its equally as hard to fit at both ends.

After a lot of pushing clp and I got it to go in but with a lot of pressure. I don't think it should be that hard, and imagine it would be a lot more difficult with the gas tube and block installed. I'm going to order another nut and see what happens.

Posted: 7/25/2013 7:56:16 PM EDT

[#12]

Quote History

Quoted:
No its the correct end. If you look close enough you can see the tab that stops next to the upper when installed on the right side if the pic. Did try both ends to make sure the rail is out of round. Its equally as hard to fit at both ends.

After a lot of pushing clp and I got it to go in but with a lot of pressure. I don't think it should be that hard, and imagine it would be a lot more difficult with the gas tube and block installed. I'm going to order another nut and see what happens.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:

http://www.tacomaworld.com/gallery/data/500/medium/20130725_230803.jpg

Here's a pic. Cant get it any further than this.

unless im missing something obvious, but thats the wrong end

edit: is the rail have the same ID from end to end? i have no idea, ive never looked

No its the correct end. If you look close enough you can see the tab that stops next to the upper when installed on the right side if the pic. Did try both ends to make sure the rail is out of round. Its equally as hard to fit at both ends.

After a lot of pushing clp and I got it to go in but with a lot of pressure. I don't think it should be that hard, and imagine it would be a lot more difficult with the gas tube and block installed. I'm going to order another nut and see what happens.

my mistake. anyway if it fits (even with a lot of effort) then it seems to be a tolerance stacking issue. a different nut is definitely worth a try

Posted: 7/25/2013 8:05:46 PM EDT

[#13]

Quote History

Quoted:
my mistake. anyway if it fits (even with a lot of effort) then it seems to be a tolerance stacking issue. a different nut is definitely worth a try

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
http://www.tacomaworld.com/gallery/data/500/medium/20130725_230803.jpg

Here's a pic. Cant get it any further than this.

unless im missing something obvious, but thats the wrong end
edit: is the rail have the same ID from end to end? i have no idea, ive never looked

No its the correct end. If you look close enough you can see the tab that stops next to the upper when installed on the right side if the pic. Did try both ends to make sure the rail is out of round. Its equally as hard to fit at both ends.

After a lot of pushing clp and I got it to go in but with a lot of pressure. I don't think it should be that hard, and imagine it would be a lot more difficult with the gas tube and block installed. I'm going to order another nut and see what happens.

my mistake. anyway if it fits (even with a lot of effort) then it seems to be a tolerance stacking issue. a different nut is definitely worth a try

Thanks for the reply! Which nut should I try? I was thinking BCM

Posted: 7/25/2013 8:46:39 PM EDT

[#14]

My experience is that if troy products don't fit on a rifle then the rifle is out of spec.
Had this happen a while ago with the same rail on a SOTA arms upper. Would not fit, period.
Got a blem bcm upper to compare it to and the sota upper was WAY off.
I would second your choice of bcm but.

Posted: 7/25/2013 10:31:28 PM EDT

[#15]

did you try the barrel nut with a armors wrench to see it it fits that.

Posted: 7/26/2013 1:55:01 AM EDT

[#16]

I got a few extra nuts if you want a couple.

Let me know and I will ship em to ya.

Posted: 7/26/2013 2:44:37 AM EDT

[#17]

On my build I used the same rail but longer with a BCM nut. It was on the snug side but it fit.

Posted: 7/26/2013 5:51:07 AM EDT

[#18]

I have installed 5 or six of these. I had the same issue with one gun. Turns out the nut was out of spec (the lugs were too big) . I replaced the nut with a high standard nut from Brownell's and the VTAC slipped right on. That is probably your issue too. The nuts are not that expensive, get one.

Posted: 7/26/2013 6:32:54 AM EDT

[#19]

Quote History

Quoted:
I got a few extra nuts if you want a couple.

Let me know and I will ship em to ya.

View Quote

HAHA! Thanks, but hold onto your nuts!

I ordered a BCM for half the price of the Armalite. I hope it's just that. After reading the reviews on PA one user said he had to file his barrel nut down in order to work.

Posted: 7/26/2013 7:13:12 AM EDT

[#20]

I had to tap mine on with the plastic end of a hammer the first time it went on. Could not get it on by hand. I removed and reinstalled it a couple of times changing things around and it got easier each time. Barrel nut was a BCM on a completed upper from them. Remember that the rail has to be cocked off center about 5 degrees when slipping over the barrel nut then rotated into final position once the barrel nut drops into the groove on the inside.

Posted: 7/26/2013 8:52:53 AM EDT

[#21]

Is it a new barrel nut? I had an issue in the past utlizing a used barrel nut that had one or more teeth on the nut SLIGHTLY damaged (bent/flattened, etc) from being removed/installed multiple times and that was my problem; it looked similar to yours. That being said i used a different barrel nut and it went on fine. Thoroughly examine each tooth on the nut and make sure you dont have one thats a problem.

Posted: 7/26/2013 9:41:58 AM EDT

[#22]

Ok, after fitting and fitting and fitting. I finally got the rail over the nut. I don't think there was anytime wrong with the nut or the rail. I would chalk this up to a newby error! Still don't think it should've been that hard, but it actually fits nice and tight!

Posted: 7/26/2013 9:49:19 AM EDT

[#23]

Quote History

Quoted:
Ok, after fitting and fitting and fitting. I finally got the rail over the nut. I don't think there was anytime wrong with the nut or the rail. I would chalk this up to a newby error! Still don't think it should've been that hard, but it actually fits nice and tight!

View Quote

They can be a little tricky to get installed but once they are mounted they are like a rock; hence their popularity. Troy puts out a great product and the alpha is def my fav handguard for under $200.