Ever cut a 20" barrel down to 18"? Gas system conflict?

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[ARCHIVED THREAD] - Ever cut a 20" barrel down to 18"? Gas system conflict?

Posted: 12/21/2005 2:03:05 PM EDT

I need some input on cutting down a 20" barrel to 18". I have the means of doing so but my main concern is with the gas system. Is there gonna be a reliability conflict concerning the gas system if i go cutting off 2"? Such as the bullet not staying in the barrel with the full size gas system. Let me know if anyone has factual info that would yield it to be not a wise thing to do.

Posted: 12/21/2005 2:11:37 PM EDT

[#1]

removed

Posted: 12/21/2005 2:23:56 PM EDT

[#2]

Alright ya an SPR build is what i have in mind. But I wasn't sure if SPRs use a full length gas system.

Posted: 12/21/2005 7:16:33 PM EDT

[#3]

My RRA 18" runs great , even with Wolf ammo,with a standard gas port. I have fired it in temps down into the low 40's with no function problems

Posted: 12/21/2005 7:46:44 PM EDT

[#4]

removed

Posted: 12/22/2005 9:52:35 AM EDT

[#5]

Quoted:
your personal results are all well and good, that's great...

but we base reliability on the results of many more than one rifle, and under a wide range of environements -- I am just relaying lessons learned: he may want to open the port a little, the SPRs have the port opened and it is not just for GP.

Of course, the best solution is the Intermediate Gas System which was developed specifically as an enhancment for the 18" barrel -- but, a person can do whatever the please I guess.

When you say intermediate, do you mean a mid length gas system, or are you refering to something a little closer to the barrel, like a 10-11 gas port location/handguard length?

Brett

Posted: 12/22/2005 9:57:43 AM EDT

[#6]

removed

Posted: 12/22/2005 10:07:33 AM EDT

[#7]

I cut mine from 24 to 18 with no problem.

Posted: 12/22/2005 10:22:22 AM EDT

[#8]

shouldn't be a problem.

Posted: 12/22/2005 11:08:53 AM EDT

[#9]

Quoted:
Quoted:
Quoted:
your personal results are all well and good, that's great...

but we base reliability on the results of many more than one rifle, and under a wide range of environements -- I am just relaying lessons learned: he may want to open the port a little, the SPRs have the port opened and it is not just for GP.

Of course, the best solution is the Intermediate Gas System which was developed specifically as an enhancment for the 18" barrel -- but, a person can do whatever the please I guess.

When you say intermediate, do you mean a mid length gas system, or are you refering to something a little closer to the barrel, like a 10-11 gas port location/handguard length?

Brett

Intermediate is a dedicated system for the 18" barrels, it is between the midlength and rifle gas systems.

www.gunzilla.com/images/VLTOR3s.JPG

Ok, cool, is that a 12" handguard then?

Brett

Posted: 12/22/2005 1:26:53 PM EDT

[#10]

Sounds good.

Posted: 12/23/2005 7:41:50 AM EDT

[#11]

i had a bushy 20" gov barrel cut to 18" and needed to open up the gas port to .090" to make it 100%.

i was shooting on a cool morning (about 45 degrees) and was getting some rounds that would not lock the bolt back on the last round in the mag. this was with winchester q3131 (not A).

other than that it cycled fine. i actually trying to sell the barrel now on the EE

Posted: 12/23/2005 8:14:41 AM EDT

[#12]

I had Gemtech cut my 20" KAC SR15 Match down to 18" - functions 100% with no change to the gas port or gas block. Both suppressed and un-suprpessed yield the same results.

Posted: 12/23/2005 10:37:41 PM EDT

[#13]

You are probably fine at 18" without touching the port, unless it's on the small side now.
At 17" you will need to open the gas port.
I don't recommend any shorter than 17" on the rifle-length gas system.
16" barrels on the rifle-length gas system get ammo sensitive.

Much more about gas systems here.

Kino-

Tell me more about "intermediate" length gas tubes.
Who makes them and where do I get them.
Are they a custom shortened rifle tube?
The basic RRA/Armalite mid-length is just the Carbine tube extended 2", but you are saying there is a mid-mid-length between normal mid-length and rifle now?

[ARCHIVED THREAD] - Ever cut a 20" barrel down to 18"? Gas system conflict?

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