any input? Gas problems! heh...

cutlass1972 · August 01, 2005, 12:55

Okay, I am getting tired of this one..... I have a G1 barrel I have been monkeying with for about a year now. It has been cut down to 16 1/4", gas tube cut in half and silver soldered on, gas port opened up, and I STILL must close the gas adjustment all the way to get it to feed reliably. This gas tube worked just fine on another build before this one so I dont think this one is oversized or anything. I am useing a Tapco gas piston (yes I tried a couple others to rule it out). and I have tried 2 different gas plugs with the same results....

only thing I have not changed out is my piston spring (original). Surely it is not too strong?

WTF????

**bykerhd** · August 01, 2005, 15:19

Couple things more to check.
Barrel timing ? If off enough it could be causing the piston to bind.
Bolt carrier binding up in the upper ? Rough or high spots in the upper causing drag.
Recoil springs too strong, too dry, too wet or dirty. Includes the rcoil spring tube.
Hammer binding ?
Hammer spring assembly binding ?
Headspace too tight ?
I'm sure there are a few I've missed. Hang in there.

cutlass1972 · August 01, 2005, 15:26

well, it now has a para carrier and para setup, however it did the exact same thing when it was a non para.

3doghouse · August 01, 2005, 17:09

If you remove the upper, and assemble it without the gas piston spring, does the piston slide with gravity only?

Blood of Tyrants · August 06, 2005, 21:56

Here is a something you might want to try. The gas bleed port on a metric rifle is drilled straight down from the top as you know.

Is there a possibility gas is leaking from between the bottom of the front sight and the gas block? You can drill the gas access hole ONLY to #29 drill bit size and tap for a 6-32 allen head set screw and then loctite it in place to eliminate that possibility.

mr fixit · August 06, 2005, 22:10

What size is the gas port? Did you open it up (the port) when you cut the barrel?

look at this thread:
other short barrel thread

ratas calientes · August 06, 2005, 22:22

G1 barrels are notoriously leaky. Many were well used. On my G1 build I had a similar problem, and it remained full-length. I silver soldered the gas tube, and that still wasn't enough. I had to open up the gas port to ~0.109 or so to finally get it to run. Hopefully you can get yours to run before the gas port gets too large. What size is your gas port now?

Rich@CGW · August 10, 2005, 13:16

If your gun will not FEED properly, You need to be looking at the areas mostly responsible for feeding and chambering. ( guide rails , feed ramps , chamber etc.. )

The least of which is the gas system, which is for extraction and recycle.

August 01, 2005, 12:55	#1
cutlass1972 Registered FALaholic #: 4492 Join Date: Oct 2001 Location: cynthiana, ky 41031 Posts: 504	any input? Gas problems! heh... Okay, I am getting tired of this one..... I have a G1 barrel I have been monkeying with for about a year now. It has been cut down to 16 1/4", gas tube cut in half and silver soldered on, gas port opened up, and I STILL must close the gas adjustment all the way to get it to feed reliably. This gas tube worked just fine on another build before this one so I dont think this one is oversized or anything. I am useing a Tapco gas piston (yes I tried a couple others to rule it out). and I have tried 2 different gas plugs with the same results.... only thing I have not changed out is my piston spring (original). Surely it is not too strong? WTF???? __________________ Drive Hard and Shoot Straight

August 01, 2005, 15:26	#3
cutlass1972 Registered FALaholic #: 4492 Join Date: Oct 2001 Location: cynthiana, ky 41031 Posts: 504	well, it now has a para carrier and para setup, however it did the exact same thing when it was a non para. __________________ Drive Hard and Shoot Straight

August 01, 2005, 17:09	#4
3doghouse Registered FALaholic #: 5240 Join Date: Jan 2002 Location: Augusta, GA USA Posts: 714	If you remove the upper, and assemble it without the gas piston spring, does the piston slide with gravity only? __________________ :fal:

August 06, 2005, 21:56	#5
Blood of Tyrants Registered FALaholic #: 1244 Join Date: Oct 2000 Location: Middle Tennessee Posts: 2,843	Here is a something you might want to try. The gas bleed port on a metric rifle is drilled straight down from the top as you know. Is there a possibility gas is leaking from between the bottom of the front sight and the gas block? You can drill the gas access hole ONLY to #29 drill bit size and tap for a 6-32 allen head set screw and then loctite it in place to eliminate that possibility. __________________ From time to time the tree of liberty must be watered with the blood of patriots and tyrants. Thomas Jefferson One day, in the not too distant future, good men and women like those that serve in Iraq, will decide that the United States isn't worth fighting for and the blame will be squarely on the shoulders of the DemocRat Party.

August 06, 2005, 22:10	#6
mr fixit Registered FALaholic #: 5663 Join Date: Feb 2002 Location: N. E. Texas Posts: 809	What size is the gas port? Did you open it up (the port) when you cut the barrel? look at this thread: other short barrel thread __________________ Check out my blog: The Fixit Shop A finely crafted weapon is a joy to see and own, no matter what it's age. "Every man is responsible for defending every woman and every child. When the male no longer takes this role, when he no longer has the courage or feels the moral responsibility, then that society will no longer be a society where honor and virtue are esteemed. Laws and government cannot replace this personal caring and commitment. In the absence of the Warrior protector, the only way that a government can protect a society is to remove the freedom of the people. And the sons and daughters of lions become sheep." -James Williams "It's a new breed," Keeton said. "They're urban raccoons, and they're not afraid."

August 01, 2005, 15:19	#2
bykerhd Dinosaur Bronze Contributor FALaholic #: 2798 Join Date: Mar 2001 Location: Burlington Vermont area Posts: 13,262	Couple things more to check. Barrel timing ? If off enough it could be causing the piston to bind. Bolt carrier binding up in the upper ? Rough or high spots in the upper causing drag. Recoil springs too strong, too dry, too wet or dirty. Includes the rcoil spring tube. Hammer binding ? Hammer spring assembly binding ? Headspace too tight ? I'm sure there are a few I've missed. Hang in there.

August 06, 2005, 22:22	#7
ratas calientes Registered FALaholic #: 1841 Join Date: Dec 2000 Location: New Mexico Posts: 7,818	G1 barrels are notoriously leaky. Many were well used. On my G1 build I had a similar problem, and it remained full-length. I silver soldered the gas tube, and that still wasn't enough. I had to open up the gas port to ~0.109 or so to finally get it to run. Hopefully you can get yours to run before the gas port gets too large. What size is your gas port now? __________________ Ratas Calientes (Hot Rats) Rats are people too!

August 10, 2005, 13:16	#8
Rich@CGW Registered FALaholic #: 167 Join Date: Jul 2000 Location: Gardnerville , NV. Near Lake Tahoe Posts: 1,826	If your gun will not FEED properly, You need to be looking at the areas mostly responsible for feeding and chambering. ( guide rails , feed ramps , chamber etc.. ) The least of which is the gas system, which is for extraction and recycle. __________________ Will work for cash & pine nuts

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