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  #1  
Unread 10-30-08, 19:22
Solomon Offline
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Help me SBR my 6920 (legally but non-NFA)

First and foremost, I do understand that I need a permanently attached device, but I am trying to make my 6920 as close to a 6921 as realistically possible and not damage the value of my Colt. My options appear to be:

Barrel replacement option: where can I buy a 6921 barrel with a Vortex permanently attached (are there better options than the Vortex, given that the A2 is too short NFA-wise for a 14.5" barrel)?

Barrel cutting option: if I get my barrel cut down to 14.7" (to use the stock A2) or 14.5" (to use a Vortex or other), will my barrel be otherwise identical to the stock 6921 14.5" barrel? (i.e., are the M203 cut and the FSP mount in the same place distance-wise from the upper on both the 6920 and 6921 barrels, and would I need to re-zero?)

Upper swap option: where can I buy (or exchange my unfired 6920 upper for) a Colt 6921 upper with a permanently attached Vortex?

Any other ideas? Thanks in advance!
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  #2  
Unread 10-30-08, 19:34
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I advise you to just enjoy it the way it is... There is no need to do anything crazy like cut 1.3 inches off the barrel...

Just my .02

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  #3  
Unread 10-30-08, 19:37
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Indeed. Chopping on a Colt barrel after it's left the factory should be illegal.

And a permmed 14.5 is almost NO different in length than a 16 with FH. Not even worth the effort.

If you already have a 14.5 than perming isn't a biggie. But a cut and perm is too much trouble for almost no gain.
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  #4  
Unread 10-30-08, 19:39
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Quote:
Originally Posted by Buck View Post
I advise you to just enjoy it the way it is... There is no need to do anything crazy like cut 1.3 inches off the barrel... B


I agree.

That's a lot of trouble, expense and possible law violation for less
than 2 inches of barrel.

Unless you look real close, you can't tell the difference anyway.
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Last edited by JBnTX; 10-30-08 at 19:41
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  #5  
Unread 10-31-08, 11:34
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Sabre Defence makes an extended A2 flash hider that when permanently attached makes a 14.5" barrel legal length. I would recommend not cutting on your barrel or permanently altering it if you are concerned about value. That being said, on my guns if I know I will never sell it or get rid of it I do what I want to make it the way I want/need it. YMMV.
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  #6  
Unread 10-31-08, 13:48
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Don't cut on a 6920...not even worth it.
If you NEED a 14.5 perm-attached FH, buy an LMT upper in 14.5 and have someone do the work.
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  #7  
Unread 10-31-08, 14:00
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I with the other guys here, I LIKE my 16" carbines better than my 14.5" with the permanent flash hider.

You you want to get a shortie, then get a 10-12" one.

Cameron
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  #8  
Unread 11-29-08, 01:54
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Here ya go,

http://www.fidelisfirearms.com/colt.htm

Then find someone to put a long Flash Suppressor on permanently.

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Last edited by IPSC_GUY; 11-29-08 at 01:57
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  #9  
Unread 11-29-08, 03:36
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Quote:
Originally Posted by Dave L. View Post
Don't cut on a 6920...not even worth it.
If you NEED a 14.5 perm-attached FH, buy an LMT upper in 14.5 and have someone do the work.
+1 on this.
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  #10  
Unread 11-29-08, 09:23
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I'll be the oddball here. Just left a barrel to be turned and cut down. Unknown mfg. HBAR that shoots OK. Not chrome lined. I wanted to get the weight off and thought I might as well get it shortened at the same time. Why? Just because I wanted to and had it off anyway. Now or never. $90 total. I wouldn't have been "happy" unless I did it...............
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  #11  
Unread 11-29-08, 09:32
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Why would it be against the law to chop a Colt barrel after it's left the factory? As long as someone qualified does the work and you end up with 16" overall with the perm. flashhider what's the problem?

I'm not saying it's worth it ... but why would it be against the law?
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Last edited by mmike87; 11-29-08 at 09:33
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  #12  
Unread 11-29-08, 09:51
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Quote:
Originally Posted by mmike87 View Post
Why would it be against the law to chop a Colt barrel after it's left the factory? As long as someone qualified does the work and you end up with 16" overall with the perm. flashhider what's the problem?

I'm not saying it's worth it ... but why would it be against the law?
NO! It SHOULD be against the law.... I'm exaggerating.

If you want a 14.5 inch Colt barrel, buy one from Fidelis. You could sell the 16" and probably about break even.

Cutting on a Colt barrel is just wrong.
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  #13  
Unread 11-29-08, 12:11
Solomon Offline
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Thanks for all the replies. Other than sending it to S.A.W. for the Reliability Package, I've decided not to make any permanent changes to it.
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  #14  
Unread 11-29-08, 13:59
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Is it unreliable now??? Just take it out and shoot it… Enjoy it the way it is… ;-)

B
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  #15  
Unread 11-30-08, 10:59
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Yeah. Forget the reliability package.
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  #16  
Unread 11-30-08, 12:01
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A 14.5" Colt M4 barrel with a permanently attached Vortex flash suppressor will be approximately 1.1" shorter than a 16" Colt barrel with an A2 flash suppressor.




Cutting a 16" 6920 barrel to 14.5" will not give you an "otherwise identical" barrel to a stock 14.5" 6921 barrel as the barrel stamps are positioned differently. While the dimensions will be the same, you will have destroyed most of the original barrel stamp in the process. You mentioned your concern for not damaging the "value" of your Colt; well in the eyes of many true Colt aficionados, this will have made the barrel next to worthless (as evidenced by many of the previously posted comments.)






M4




Your best bet is to try to find a 6921 barrel (or better yet, an M4A1 barrel [6921HB]) and have a Vortex flash suppressor permanently attached and then swap out the barrels.




Last edited by Molon; 11-30-08 at 12:14 Reason: ..
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  #17  
Unread 11-30-08, 14:06
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I never understood the point of sub-16" barrels with a permanently attached FS to bring it to legal length. You get all of the negatives of an SBR with none of the advantages.

This applies less to 14.5" barrels than 10.5" barrels with permanent flash hiders.
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  #18  
Unread 11-30-08, 16:42
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Just an observation, but is the gas port in the barrel a different size for 16" versus 14.5"? If it is, a shortened barrel could create reliability or function problems.
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  #19  
Unread 11-30-08, 20:34
Molon Offline
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Quote:
Originally Posted by Guntoter View Post
Just an observation, but is the gas port in the barrel a different size for 16" versus 14.5"? If it is, a shortened barrel could create reliability or function problems.
IIRC the gas port diameter is the same for the 14.5" and 16" barrels.
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  #20  
Unread 11-30-08, 20:40
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Quote:
Originally Posted by Molon View Post
IIRC the gas port diameter is the same for the 14.5" and 16" barrels.

Cool, I did not know that.
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