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  #1  
Unread 10-18-09, 14:28
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12 inch omega rail?

I was going to get one to put on my lmt upper with shaved front sight post untill I read on bravocompany's sight that it is not for use with a lo pro gas block or any gas system other than rifle. My question is why not? Will it cause any problems? Your input is appreciated, thanks.
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Unread 10-18-09, 14:31
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It will fit under a VERY low profile gas block like a shaved FSB, Vltor, YHM, or Stag. I have successfully installed on over a Noveske marked Vltor block with no problem.
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Unread 10-18-09, 14:58
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As mentioned before it will fit under if shaved very cleanly. I know ADCO can do this for you for like $30.
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Unread 10-18-09, 15:06
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Quote:
Originally Posted by greene View Post
I was going to get one to put on my lmt upper with shaved front sight post untill I read on bravocompany's sight that it is not for use with a lo pro gas block or any gas system other than rifle. My question is why not? Will it cause any problems? Your input is appreciated, thanks.
I a while ago shaved a .625" FSB to fit under a 12" Omega (CMMG barrel). It had a perm. attached flash hider. I had to make it WAY small. I highly doubt you'll get a .750" FSB shaved to fit under it....

Here's a pic of the .625" FSB shaved in place on the barrel before refinishing with Norrells moly resin.


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  #5  
Unread 10-18-09, 15:12
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Quote:
Originally Posted by gotm4 View Post
I a while ago shaved a .625" FSB to fit under a 12" Omega (CMMG barrel). It had a perm. attached flash hider. I had to make it WAY small. I highly doubt you'll get a .750" FSB shaved to fit under it....


I have not done this, but why would a .625 shaved FSB be lower than a .750? The hole for the barrel is different but they should be the same height at the gas tube exit location...

Just thinking out loud
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  #6  
Unread 10-18-09, 15:24
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Quote:
Originally Posted by eguns-com View Post
I have not done this, but why would a .625 shaved FSB be lower than a .750? The hole for the barrel is different but they should be the same height at the gas tube exit location...

Just thinking out loud
You're able to the the .625" FSB smaller.....

edited to add: It's not the height of the FSB it's the width of the .750" FSB, you can only get it so thin, the .625" FSB starts off smaller.
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Last edited by Robb Jensen; 10-18-09 at 15:34
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Unread 10-18-09, 17:11
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The problem isn't getting it to fit, because it does I've tried it with a 9 inch omega, but is why do they not reccomend using a lo pro gas block with it. Once installed I don't see their being any kind of issues, what possible problems could occur if any?
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Unread 10-18-09, 17:28
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Quote:
Originally Posted by greene View Post
The problem isn't getting it to fit, because it does I've tried it with a 9 inch omega, but is why do they not reccomend using a lo pro gas block with it. Once installed I don't see their being any kind of issues, what possible problems could occur if any?

The clearance is so close to gas blocks that with 12" rails you can just tap the rail and it'll flex a little and actually hit the gas block. This isn't good.
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Unread 10-18-09, 19:27
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Robb

So you're saying you can get the FSB shaved to get the rail to fit, but it's still too big where any pressure on the rail will cause contact to it resulting in less than desireable results? I was just curious as to what Steve does at his place with his shaving/repark technique to accomplish this. I don't think it'll be a problem for me since I'm using a 13.2 LaRue rail, but was thinking about going with the DD like the OP. Thanks.
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  #10  
Unread 10-18-09, 20:46
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I have an Omega 12.0 installed over a PRI low-pro with ample clearance (meaning I can't force it to make contact with hand pressure and there are no signs that it's contacting under recoil), and it was previously over a VLTOR low-pro with same results...

I just shaved down an A2 for my 6.8 and it fits under my Troy rails, but it took a LOT of time with a file to achieve enough clearance, and there's no way I could get it down far enough to clear my DD while still leaving enough structure to trust the strength...

Last edited by Hell_Bent; 10-18-09 at 20:52
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  #11  
Unread 10-18-09, 21:12
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Quote:
Originally Posted by JackOSU View Post
Robb

So you're saying you can get the FSB shaved to get the rail to fit, but it's still too big where any pressure on the rail will cause contact to it resulting in less than desireable results? I was just curious as to what Steve does at his place with his shaving/repark technique to accomplish this. I don't think it'll be a problem for me since I'm using a 13.2 LaRue rail, but was thinking about going with the DD like the OP. Thanks.
The DD Omega has the tightest inside clearance of ANY rail/FF tube I've ever seen. I can shave and do so many times per month FSBs to fit under many FF tubes/rails. Steve probably does similar to what I do. I use a plasma cutter, a grinder, a disc sander and a bead blaster, then coat with Norrels moly resin. This is what mine look like.




The shaved FSB all the way on the right will fit under a DD Lite Rail, RISII, LaRue, YHM and most other rails. It will BARELY fit under a DD Omega and when it does all it takes is you to hit the rail firmly with your hand and it'll run into the gas block.
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  #12  
Unread 10-19-09, 02:08
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Looks good Robb. How does the moly resin compare to a park job? I assume the overall function is pretty much the same?
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  #13  
Unread 10-19-09, 06:27
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Quote:
Originally Posted by JackOSU View Post
Looks good Robb. How does the moly resin compare to a park job? I assume the overall function is pretty much the same?
Moly resin is actually best over parkerizing. But it does really well on raw carbon or stainless steel that's been blasted. It doesn't cook off.
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