PDA

View Full Version : Help me SBR my 6920 (legally but non-NFA)



Solomon
10-30-08, 18:22
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!

Buck
10-30-08, 18:34
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

B

markm
10-30-08, 18:37
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.

JBnTX
10-30-08, 18:39
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.

Josh_Denny
10-31-08, 10:34
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.

Dave L.
10-31-08, 12:48
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.

Cameron
10-31-08, 13:00
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

IPSC_GUY
11-29-08, 00:54
Here ya go,

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

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

IPSC_GUY
SIERRA II ALPHA

CarlosDJackal
11-29-08, 02:36
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.

peasant
11-29-08, 08:23
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...............

mmike87
11-29-08, 08:32
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?

markm
11-29-08, 08:51
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.

Solomon
11-29-08, 11:11
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.

Buck
11-29-08, 12:59
Is it unreliable now??? Just take it out and shoot it… Enjoy it the way it is… ;-)

B

markm
11-30-08, 09:59
Yeah. Forget the reliability package.

Molon
11-30-08, 11:01
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.


http://www.box.net/shared/static/inxrnrnvm6.jpg

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.)



http://www.box.net/shared/static/ck8lsid4r3.jpg


M4
http://www.box.net/shared/static/nmjvjpcfua.jpg



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.



http://www.box.net/shared/static/r1dpv5sx6t.jpg

Dave_M
11-30-08, 13:06
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.

Guntoter
11-30-08, 15:42
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.

Molon
11-30-08, 19:34
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.

Guntoter
11-30-08, 19:40
IIRC the gas port diameter is the same for the 14.5" and 16" barrels.


Cool, I did not know that.

mmike87
11-30-08, 20:12
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.

Dammit - that went right over my head and I missed it! :o

scottryan
11-30-08, 22:32
Permanently attaching a flash hider is stupid.

By the time you are done with all this BS, you could have bought an SBR.

Mailing barrels back and forth, arranging a welder, swapping barrels, lowering the value of the factory Colt barrel. All bullshit.