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1/8/2014 6:17:57 PM EDT
m having a problem with my fortis rail. I finally got around to shooting my ar and while sighting it in I found that I couldn't hit paper. I adjusted the front site (MI) as far up as it would go and finally started hitting paper but had to aim off target. I took it home and after looking at it, I noticed that the barrel don't sit centered in the rail. Anyone else notice problems like this with free float rails? I mean it's not like the rail is held on by much. Heres some pics.Am I doing something wrong? I emailed Fortis and they didn't seem too inclined to help. The customer service guy basically said to try reinstalling it and to not tighten it too much. The cap that holds it on is a pain to get off too.





1/8/2014 6:31:09 PM EDT
[#1]
What barrel do you have?
1/8/2014 6:43:42 PM EDT
[#2]
We have found when installing these you have to be evenly tighten the 4 screws you cant do 1 side then the other or it can end up off center.
1/8/2014 6:56:10 PM EDT
[#3]
BCM 14.5
1/8/2014 6:58:42 PM EDT
[#4]
I did it in a criss-cross pattern like you would a wheel on a car. If I take the screws out, do you think I can adjust the position of the barrel/rail as I tighten?
1/8/2014 7:18:37 PM EDT
[#5]
I had that same issue and Fortis ended up replacing it via Rainier Arms who actually handles all of their warranty claims.  Who emailed you back? The guy I delt with was named Paul and he got me squared away asap.

The correct torque is 60 - 70 INCH pounds and you want to tighten in stages using a criss cross pattern. Do NOT use ANY locking compounds (like loctite) or the inserts may back out when losening the screws. Do NOT over tighten!
1/8/2014 7:19:48 PM EDT
[#6]
Yea it's definitely off centered. Try again being aware of where the barrel is keeping it centered. I'm sure you'll get it this time.
1/8/2014 7:22:48 PM EDT
[#7]
Another reason why I like monolithics
1/8/2014 7:23:40 PM EDT
[#8]
Quote History
Quoted:
Yea it's definitely off centered. Try again being aware of where the barrel is keeping it centered. I'm sure you'll get it this time.
View Quote


If the barrel nut is in spec and the REV isn't damanged it will center itself as you tighten the clamp.

ETA:

Tightening one side at a time will cause it to be off center like StoneFire said.
1/8/2014 7:48:27 PM EDT
[#9]
I'd do as previous posters have said and try to reinstall it....looks like you have a pretty good gap between the receiver and rail too, I'd snug that up... and then slowly tighten up the screws in a criss cross pattern little by little to make sure the rail stays straight.
1/8/2014 7:52:47 PM EDT
[#10]
Thanks for the help. Yes the guy's name was Paul. He said he never heard of the problem before. Ill take it apart and reinstall it and see what happens. If I have the same problem, Ill look into sending it back.
1/9/2014 3:01:58 AM EDT
[#11]
OP, is the rail able to move around any while tight?
1/9/2014 9:36:39 AM EDT
[#12]
There is a little bit of flex in the rail.
1/9/2014 2:24:27 PM EDT
[#13]
Mine did that with a PSA barrel nut. No matter what I tried it just would not straiten out. I switched it with a Rock River and it was fine.
1/9/2014 4:47:33 PM EDT
[#14]
Yea just try reinstalling it. If it doesn't work, you need to get whatever barrel nut the manufacturer calls for. I highly doubt that the problem is in the rail.
1/9/2014 4:57:13 PM EDT
[#15]
OP, I just received my 14" REV tonight. I was about to install it and noticed the receiver end looks to be milled in an odd way. I'll post more details and some pics once I get it installed.
1/9/2014 7:39:59 PM EDT
[#16]
Livindead, it may not be you.

Try to re-install as others have suggested but I too am having issues with my REV rails concerning this very issue.

I have a 12" and a 14", that is how much I love my REV.

I have had both installed for awhile and never really thought there was a problem until one of my local boys noticed that his REV rail will "shift" on the barrel nut. I was curious to see if it is a problem I have and just never noticed it. I did find both my 12" and 14" will "shift/move" and I am not talking about "flexing" I am talking about movement on the barrel nut, putting the barrel out of centered alignment and it staying there.

To test I removed my upper with the 12" and placed it on a flat surface. I then put pressure, not a lot BTW on the center of the upper and saw the rail move and stay, not spring back to center. Upon further playing with it I found the clamp design on the barrel nut because it is not a super precision tight allows for it to move / shift on the barrel nut. I did this with my 14" upper as well and it did the same thing. Tried to remove and reinstall the rails several times, troubleshooting and close examining each time and it did the same thing, each time. Pretty depressing. :(

The problem with the clamp design on the REV is you can only tighten it so much. Once the clamshell meets the other side you can only tighten so much, if you go too far you can pull out the threaded inserts and damage the rail.
1/9/2014 7:42:04 PM EDT
[#17]
Quote History
Quoted:
Livindead, it may not be you.

Try to re-install as others have suggested but I too am having issues with my REV rails concerning this very issue.

I have a 12" and a 14", that is how much I love my REV.

I have had both installed for awhile and never really thought there was a problem until one of my local boys noticed that his REV rail will "shift" on the barrel nut. I was curious to see if it is a problem I ave and just never noticed it. I did find both my 12" and 14" "shift" I am not talking about "flexing" I am talking about movement on the barrel nut, putting the barrel out of centered alignment and it staying there.

To test I removed my upper with the 12" and placed it on a flat surface. I then put pressure, not a lot BTW on the center of the upper and saw the rail move and stay, not spring back to center. Upon further playing with it I found the clamp design on the barrel nut because it is not a super precision tight allows for it to move / shift on the barrel nut. I did this with my 14" upper as well and it did the same thing. Tried to remove and reinstall the rails several times, troubleshooting and close examining each time and it did the same thing, each time. Pretty depressing. :(

The problem with the clamp design on the REV is you can only tighten it so much. Once the clamshell meets the other side you can only tighten so much, if you go too far you can pull out the threaded inserts and damage the rail.
View Quote


I'd try another barrel nut and see what happens.
1/9/2014 7:45:02 PM EDT
[#18]
I have gone through a total of 5 barrel nuts and two different upper receivers.

All of them have done the same thing. Rail installed perfectly, centered as should be, put pressure on the rail in either direction and it "moves" on the barrel nut.

There is too much space between the rail and the upper receiver. The barrel nut is a smooth surface and you can only tighten to a certain point, there needs to be a texture to "GRAB" onto and stay solid in place.

I would be interested if others experimented with their REV rails to see if theirs moves as well. I know one other that has the same problem as I do.
1/9/2014 7:52:22 PM EDT
[#19]
Use a level that is at least the length of the freefloat rail's and upper receiver's picatinny rail. Slide the freefloat over the barrel nut, and then rest the complete upper upside down on the level. As you tighten the screws, make sure the level stays flush with the upper and rail.
1/9/2014 9:14:58 PM EDT
[#20]
Well I got mine all put together and have the same problem as the OP. The rail is a bit too low and a fair amount too far to the left. It's slightly worse than the pics make it out to be. It's very close to 1/8" off center and a bit more than 1/16" low. I don't have a down-the-muzzle view like the OP, but it looks damn near identical.



It's a brand new BCM barrel and barrel nut and a new Aero Precision upper.

I noticed after unpacking it that the receiver end of the rail isn't milled the same on the left and right sides. I'm not sure if that has anything to do with the issue, but it seemed strange nonetheless.

This pic is from the receiver end and the rail is right side up. You should be able to see closest to the inside that there's a dip on the left and a hump on the right.



This pic is also from the receiver end, but the rail is upside down. You should be able to see closest to the inside that there's a dip on the left and the right is flat.



And this pic shows the threads of the threaded insert poking through. Looks to me like they're not drilled in the correct place.



I then went ahead and installed it. I was careful to tighten the hex bolts evenly and not excessively tight. I took it off and back on several times, altering how I tightened to see if it sequence made any difference. It did not. The rail ended up in the exact same position every time. It was also immediately clear that alignment of the clamp and the rail was slightly out of whack, as the hex bolts on one side threaded easily and the hex bolts on the other side seemed to drag quite badly on the inside of the counter bores.

It looks positioned just about right as seen in this pic.



However, when looking at the left and right sides, the misalignment of the clamp to the rail becomes fairly apparent.

Here's the left side of the rifle.



And the right.



There are a few more pics in my imgur album: http://imgur.com/a/wbYKj/all

I'm happy to take additional photos.

So... livindead... does this look similar to your issue?
1/10/2014 10:55:31 AM EDT
[#21]
Quote History
Quoted:
Well I got mine all put together and have the same problem as the OP. The rail is a bit too low and a fair amount too far to the left. It's slightly worse than the pics make it out to be. It's very close to 1/8" off center and a bit more than 1/16" low. I don't have a down-the-muzzle view like the OP, but it looks damn near identical.

<a href="http://imgur.com/Js8POoY" target="_blank">http://i.imgur.com/Js8POoYl.jpg</a>

It's a brand new BCM barrel and barrel nut and a new Aero Precision upper.

I noticed after unpacking it that the receiver end of the rail isn't milled the same on the left and right sides. I'm not sure if that has anything to do with the issue, but it seemed strange nonetheless.

This pic is from the receiver end and the rail is right side up. You should be able to see closest to the inside that there's a dip on the left and a hump on the right.

<a href="http://imgur.com/1Ix6Qnj" target="_blank">http://i.imgur.com/1Ix6Qnjl.jpg</a>

This pic is also from the receiver end, but the rail is upside down. You should be able to see closest to the inside that there's a dip on the left and the right is flat.

<a href="http://imgur.com/bxvG1MO" target="_blank">http://i.imgur.com/bxvG1MOl.jpg</a>

And this pic shows the threads of the threaded insert poking through. Looks to me like they're not drilled in the correct place.

<a href="http://imgur.com/P405LKb" target="_blank">http://i.imgur.com/P405LKbl.jpg</a>

I then went ahead and installed it. I was careful to tighten the hex bolts evenly and not excessively tight. I took it off and back on several times, altering how I tightened to see if it sequence made any difference. It did not. The rail ended up in the exact same position every time. It was also immediately clear that alignment of the clamp and the rail was slightly out of whack, as the hex bolts on one side threaded easily and the hex bolts on the other side seemed to drag quite badly on the inside of the counter bores.

It looks positioned just about right as seen in this pic.

<a href="http://imgur.com/70LTEi2" target="_blank">http://i.imgur.com/70LTEi2l.jpg</a>

However, when looking at the left and right sides, the misalignment of the clamp to the rail becomes fairly apparent.

Here's the left side of the rifle.

<a href="http://imgur.com/LvVeccq" target="_blank">http://i.imgur.com/LvVeccql.jpg</a>

And the right.

<a href="http://imgur.com/AQCJGzH" target="_blank">http://i.imgur.com/AQCJGzHl.jpg</a>

There are a few more pics in my imgur album: http://imgur.com/a/wbYKj/all

I'm happy to take additional photos.

So... livindead... does this look similar to your issue?
View Quote


Yes it does look similar. My upper is a BCM cosmetic blem. Im wondering if that has anything to do with it. Im getting advise from so many different angles and I have no idea what to go off of. Somebody also sent me this:
http://www.ar15.com/archive/topic.html?b=3&f=12&t=451851
1/10/2014 11:40:02 AM EDT
[#22]
Hmm. That's an interesting thread, but I don't really think I have a problem with my upper receiver or barrel. I think it's fairly unlikely considering we both seem to have the same issue -- yours on a BCM upper and mine an Aero Precision. Is your barrel nut BCM? That might be another common component, as mine is BCM.

I have a really nice Lee Valley Veritas straight edge that I'll check with tonight to be sure of barrel to upper alignment, but the less expensive straight edge I used last night after installing my barrel confirmed no issues with the barrel or receiver being misaligned.

At this point, I'm leaning toward the issue being with the rail itself. The clamp seems okay and it's making good contact with the barrel nut. The rail doesn't seem to align with the clamp properly, which may or may not be contributing to the issue.

Is your REV also milled strangely where it meets the clamp like mine is? I'm curious to know if anyone else's REV looks like that.

Can you also see the threads of the threaded insert poking through that inside corner? That makes me think the threaded inserts weren't placed properly and seems like a prime candidate for the cause of this particular issue.

I IM'd Rainier and pointed them this way to see if they might have anything to add.
1/10/2014 2:37:21 PM EDT
[#23]
I checked the alignment of the barrel to the upper receiver with a good straightedge and everything looks fine. I figure it could still be the barrel nut or the rail itself. I called and spoke to Rainier Arms, who requested I send pictures. After seeing them, they said they'd replace the rail.
1/10/2014 4:52:35 PM EDT
[#24]
Quote History
Quoted:
I checked the alignment of the barrel to the upper receiver with a good straightedge and everything looks fine. I figure it could still be the barrel nut or the rail itself. I called and spoke to Rainier Arms, who requested I send pictures. After seeing them, they said they'd replace the rail.
View Quote


I have yet to take mine apart to look at it. I might check it out tonight. Ill keep you posted. My barrel nut IS bcm. Im wondering if that has anything to do with it.
1/10/2014 6:01:37 PM EDT
[#25]
Quote History
Quoted:
I checked the alignment of the barrel to the upper receiver with a good straightedge and everything looks fine. I figure it could still be the barrel nut or the rail itself. I called and spoke to Rainier Arms, who requested I send pictures. After seeing them, they said they'd replace the rail.
View Quote


Rainier Arms is always really good with customer service!  

I am wondering the odds that two of you have defective rails or there is a similar situation with the upper and barrel nuts.


My status; I got my precision CORE15 barrel nut in today. Measured and it is a .5 millimeters larger in diameter, figured surely it would stop my shifting of the rail. Nope, while it feels a little tighter I was able to manipulate and move the REV rail out of alignment still.

If I was the kind of person that doesn't actually use my back up sights I would probably not care, but two different REV rails, now 6 different barrel nuts and two different upper receivers and the rail moves/shifts around. I may be overly picky but  this is unacceptable to me. I really LOVE these rails too, I like FORTIS. Just wish my outcome was different.

Good luck guys!
1/10/2014 6:08:34 PM EDT
[#26]
Quote History
Quoted:


Rainier Arms is always really good with customer service!  

I am wondering the odds that two of you have defective rails or there is a similar situation with the upper and barrel nuts.


My status; I got my precision CORE15 barrel nut in today. Measured and it is a .5 millimeters larger in diameter, figured surely it would stop my shifting of the rail. Nope, while it feels a little tighter I was able to manipulate and move the REV rail out of alignment still.

If I was the kind of person that doesn't actually use my back up sights I would probably not care, but two different REV rails, now 6 different barrel nuts and two different upper receivers and the rail moves/shifts around. I may be overly picky but  this is unacceptable to me. I really LOVE these rails too, I like FORTIS. Just wish my outcome was different.

Good luck guys!
View Quote View All Quotes
View All Quotes
Quote History
Quoted:
Quoted:
I checked the alignment of the barrel to the upper receiver with a good straightedge and everything looks fine. I figure it could still be the barrel nut or the rail itself. I called and spoke to Rainier Arms, who requested I send pictures. After seeing them, they said they'd replace the rail.


Rainier Arms is always really good with customer service!  

I am wondering the odds that two of you have defective rails or there is a similar situation with the upper and barrel nuts.


My status; I got my precision CORE15 barrel nut in today. Measured and it is a .5 millimeters larger in diameter, figured surely it would stop my shifting of the rail. Nope, while it feels a little tighter I was able to manipulate and move the REV rail out of alignment still.

If I was the kind of person that doesn't actually use my back up sights I would probably not care, but two different REV rails, now 6 different barrel nuts and two different upper receivers and the rail moves/shifts around. I may be overly picky but  this is unacceptable to me. I really LOVE these rails too, I like FORTIS. Just wish my outcome was different.

Good luck guys!


Your not being picky. Free float rails are meant to lock up solid and NOT shift around.
1/11/2014 10:46:09 AM EDT
[#27]
Quote History
Quoted:


Your not being picky. Free float rails are meant to lock up solid and NOT shift around.
View Quote


I know it is not suppose to move, a lot of people have these rails and no problems. While I tend to side with the fact I usually have Irish black luck this is just odd that none of my simple solutions have worked. Instead of trying a few other ideas I have in my head, I decided to reduce my anxiety / stress level and I am just going a different route,  not deal or worry about this anymore. :)
1/15/2014 10:19:50 AM EDT
[#28]
I received my replacement rail today. This one also has the odd milling on the receiver end and the threads of one of the threaded inserts was coming through the inside corner closest to it. I was a bit apprehensive since it had the same characteristics as the one I had sent in.

Fortunately, this one installed just fine, so I have no idea what was causing the other one not to align properly. RA just said it sounded as if it might be out of spec. In any case, all is well now.

The old rail was close to 1/8" off left to right and 1/16" off top to bottom. The new one measured in at around 0.010" off center both left to right and top to bottom, which is fantastic.
1/15/2014 4:50:38 PM EDT
[#29]
Quote History
Quoted:
I received my replacement rail today. This one also has the odd milling on the receiver end and the threads of one of the threaded inserts was coming through the inside corner closest to it. I was a bit apprehensive since it had the same characteristics as the one I had sent in.

Fortunately, this one installed just fine, so I have no idea what was causing the other one not to align properly. RA just said it sounded as if it might be out of spec. In any case, all is well now.

The old rail was close to 1/8" off left to right and 1/16" off top to bottom. The new one measured in at around 0.010" off center both left to right and top to bottom, which is fantastic.
View Quote


Glad they got you squared away
1/26/2014 5:26:49 PM EDT
[#30]
Hope I dont have this issue. Just dropped off my upper to get pinned and I have a bcm barrel nut too!
1/26/2014 6:22:27 PM EDT
[#31]
When I installed mine it was off center about the same as yours.  After I got to lookin at it the pin for the dust cover was just barely sticking out enough to keep the rail from snugging up against the receiver. You might check that out before you get into any major repairs
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