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 How to tell what length gas tube to get.
easttntactical  [Member]
7/18/2009 11:03:43 PM
If I was to order a barrel from Midwayusa, how do I tell what length gas tube to order with it?
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Winn  [Team Member]
7/18/2009 11:09:11 PM

What is the bbl. length ?

easttntactical  [Member]
7/18/2009 11:10:12 PM
it will be either 18 or 20
JoshAston  [Team Member]
7/19/2009 5:22:34 AM
18" barrels will be either mid length or rifle length. 20" barrels should be rifle length. It should say in the description what length of gas system they're set up for.
Jusbo47  [Team Member]
7/19/2009 11:51:04 AM
16 inch barrel––––- carbine length gas tube


18 inch barrel––- depends on where the gas hole is drilled

20 inch barrel–––– rifle length gas tube
Winn  [Team Member]
7/19/2009 12:35:28 PM
Originally Posted By Jusbo47:

14.5 inch barrel - most likely a carbine length gas tube

16 inch barrel–––– carbine mid-length gas tube

18 inch barrel–– depends on where the gas hole is drilled ... mid, intermediate or rifle

20 inch barrel–––– rifle length gas tube


fixed.


Also,
http://www.ar15.com/forums/topic.html?b=3&f=118&t=452344

kteaton  [Member]
7/19/2009 4:30:29 PM
Originally Posted By Winn:
Originally Posted By Jusbo47:

14.5 inch barrel - most likely a carbine length gas tube

16 inch barrel–––– carbine mid-length gas tube

18 inch barrel–– depends on where the gas hole is drilled ... mid, intermediate or rifle

20 inch barrel–––– rifle length gas tube


fixed.


Also,
http://www.ar15.com/forums/topic.html?b=3&f=118&t=452344



That edit still isn't 100% accurate. Many 16" bbls come in carbine length. Plus for all we know the OP could have a 16" dissy. He's really the only one that can help himself unless he posts pics or contacts Midway.
Winn  [Team Member]
7/19/2009 5:21:46 PM

The point is ... that given the various advances / options currently available, most anyone opting for a carbine length gas system on a 16" bbl. should probably go back to school.

Primos  [Member]
7/19/2009 9:51:06 PM
Originally Posted By Winn:

The point is ... that given the various advances / options currently available, most anyone opting for a carbine length gas system on a 16" bbl. should probably go back to school.



Carbine length gas systems work just fine.
Primos  [Member]
7/19/2009 9:52:12 PM
Originally Posted By Winn:
Originally Posted By Jusbo47:

14.5 inch barrel - most likely a carbine length gas tube

16 inch barrel–––– carbine mid-length gas tube

18 inch barrel–– depends on where the gas hole is drilled ... mid, intermediate or rifle

20 inch barrel–––– rifle length gas tube


fixed.


Also,
http://www.ar15.com/forums/topic.html?b=3&f=118&t=452344




The most common style on 16" barrels is NOT mid length gas system.
FP2000H  [Team Member]
7/19/2009 10:23:17 PM
Originally Posted By Primos:
Originally Posted By Winn:
Originally Posted By Jusbo47:

14.5 inch barrel - most likely a carbine length gas tube

16 inch barrel–––– carbine mid-length gas tube

18 inch barrel–– depends on where the gas hole is drilled ... mid, intermediate or rifle

20 inch barrel–––– rifle length gas tube


fixed.


Also,
http://www.ar15.com/forums/topic.html?b=3&f=118&t=452344




The most common style on 16" barrels is NOT mid length gas system.


This is true, and the quote about anyone getting a 16" barrel in a carbine gas system needing to go back to school isn't quite fair. I plan to have my LMT 16" barrel cut and recrowned by Rainier Arms when I SBR the weapon sometime next year. That's cheaper than buying a whole new barrel and the LMT barrel won't be anywhere close to worn by next year. I don't shoot it hardly enough. The OP's rifle is probably a carbine length. What are the distances the holes are drilled at? Someone?
phatjohn  [Member]
7/19/2009 11:33:49 PM
Ok, you guy's just confused me, are there 2 or 3 different length gas tubes?
Russ4777  [Team Member]
7/20/2009 12:04:32 AM
Three.

Carbine, mid, and rifle. Check the specs in Midway's ad. They are pretty good about describing stuff.
RD001  [Member]
7/20/2009 12:07:50 AM
Yes, there are many different types of gas tubes.

14.5" would be carbine.

For 16" barrels, there are carbine and mid-length.

For 18" There are usually rifle and mid length (or intermediate if you are cool).

For 20" I have never herd of anything other than rifle length.

The point is it depends on your barrel. It will almost defiantly tell you on the product page. If you still can't find it, just post a link to the barrel in question and I'm sure someone could help you out.
Primos  [Member]
7/20/2009 12:12:21 AM
There's also a shorter length gas system/tube for 7.5" pistol/SBR barrels. Just an FYI.
PropDoc  [Industry Partner]
7/20/2009 6:22:21 AM
Originally Posted By easttntactical:
If I was to order a barrel from Midwayusa, how do I tell what length gas tube to order with it?


Midway describes their barrel pretty well, and tells which gas tube length you will need. If from another company, then you may have to go by what they call the barrel. Pistol =Pistol length, CAR = Carbine, Mid = Mid-Length, Intermediate = Intermediate, Rifle = Rifle length. They may say 16" CAR, or 16" MID, etc, and the length of gas system is there.

So, we have now learned there are currently 5 production gas SYSTEM lengths. Gas TUBE lengths are a different story. Get the right gas tube, for the length of system, you will be fine.

yolop  [Member]
7/20/2009 8:54:33 AM
After reading this entire page I have a simple solution



MEASURE IT.
Take out a measuring device, a tape measure would work best since Bravo Company wouldn't know how to measure 4.1 legos, and measure from the barrel to the gas block. Then find the closest sized gas tube. I had a midlength on a 16 inch barrel. Some people run carbine length.


You could also call the Manf. and ask.
Winn  [Team Member]
7/20/2009 10:07:28 AM
Originally Posted By Primos:
Originally Posted By Winn:

The point is ... that given the various advances / options currently available, most anyone opting for a carbine length gas system on a 16" bbl. should probably go back to school.



Carbine length gas systems work just fine.


I didn't say they don't work

However, the fact of the matter is that generally speaking, the MLGS is a much better solution for a 16" bbl.

The carbine length gas system was originally designed for & intended to be used on an ~ 11" barrel ...

... you do the math.

engineer2001  [Member]
7/20/2009 12:39:02 PM
Originally Posted By RD001:
Yes, there are many different types of gas tubes.

14.5" would be carbine.

For 16" barrels, there are carbine and mid-length.

For 18" There are usually rifle and mid length (or intermediate if you are cool).

For 20" I have never herd of anything other than rifle length.

The point is it depends on your barrel. It will almost defiantly tell you on the product page. If you still can't find it, just post a link to the barrel in question and I'm sure someone could help you out.


Well, that list is still wrong. CMMG sells 14.5" barrels in midlength gas, and DPMS sells 16" barrels with rifle-length gas. Plus, there is a pistol gas system too for the really short barrels and an intermediate system Dave from ADCO mentions above.

You are right overall, however. Basically, you have to check with whomever is selling the barrel. As long as the barrel is long enough, you can get a gas system that you choose. For instance, a 10.5" barrel can't have a rifle gas system because the barrel is too short, but you could get a 16" barrel with carbine, middy, or rifle gas.

Edit: JSE Surplus got a batch of SS barrels that surprised them.
http://www.jsesurplus.com/wilsonarmsnm1x816inchbarrelwithgastubeandpingunsmithspecial.aspx
gee223  [Member]
7/20/2009 2:45:05 PM
Run it without one, it will work better!
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