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Discussion Starter · #1 ·
Visited a fellow shooting enthusiest a while ago, a traditional 1 year trek to Vermont. I pretty much hand my buddy the AR and several hundred rounds of ammo and the gun is his for the weekend in appreciation for his hospitality.


Anyhow he decided to give the gun a good cleaning for me and I now have an issue of the gun not cycling correctly. Every round short strokes. Is it physically possible to install the gas tube upside down? I see nothing else wrong and I havent located my hand guard removal tool yet to verify and inspect.


Any other thoughts?

Tia
drew
 

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You can't really install it upside down without bending the heck out of it, but even then if everything goes to the right place, tube through hole, carrier slides over the tube, it shoudl still work.

With shortstroking, check the bolt for carbon, tightness of the upper receiver, and make sure the bolt still unlocks easily and is not overly firm on the cam movement.

Other than making sure the gas port is clean of debris and the gas tube is unobstructed.

After all of this, make sure it's not an ammo issue.
 

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Discussion Starter · #3 ·
The bolt is immaculate and everything feels and looks fine when cycled manually. Ill check the gas port next...thanks
 

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imschur said:
... I havent located my hand guard removal tool yet to verify and inspect...
If you have a second set of hands to help, you don't need the tool to remove the hand guards.

Any chance the charging handle is out of the groove and rubbing the bolt carrier assembly? Have you torn down the upper yet?
 

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Discussion Starter · #5 ·
Madhouse said:
imschur said:
... I havent located my hand guard removal tool yet to verify and inspect...
If you have a second set of hands to help, you don't need the tool to remove the hand guards.

Any chance the charging handle is out of the groove and rubbing the bolt carrier assembly? Have you torn down the upper yet?
Yeah everything in the upper looks good. No funny wear spots or anything out of the ordinary. Like new actually. Thats why Im leaning towards something with the gas system.

I need 2 1/2 hands as Im missing the fingers on my right hand beyond the knuckle :lol: :-D

thanks
 

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Make sure the gas rings are not lined up, I get AR's in work with this quite a bit. I always recomend the one piece gas ring.
 

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Discussion Starter · #7 ·
fatcat said:
Make sure the gas rings are not lined up, I get AR's in work with this quite a bit. I always recomend the one piece gas ring.
I didnt pay attention to the rings but Ill look at that. Im not familiar with the one piece design but Im going to google it now.
 

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It seems to fix some rifles, some dont give a crap and ive seen carbines work 100% with no rings to speak of. The time when it helps the most is shooting Wolf or Brown bear. Your rings should be fine in terms of wear with so few rounds fired.

Another thing you can try is break cleaner in the gas tube and gas block or just replace the tube...

What kind of ammo are you/where you running?
 

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Discussion Starter · #9 ·
Alrighty, the ammo is PMC.

I located my handguard removal tool so I worked that end. I soaked the tube in some Hoppes all day. When I emptied it the solution had turned blue. Im guessing this means there was copper fouling. Am I correct and would this be normal?

How do I verify the gas port in the barrel is not blocked? Also the outside of the gas tube was pretty cruddy for about 1 1/2" from the sight base, is this normal?

thanks guys

drew
 

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Should not be any copper in the tube unless a jacket part is stuck in there. As for the dirtyness, its fine. Just make sure the hole in the gas tube is clear.

Only way to tell is to test shoot it.

Is this a 16.6 or a 20 inch barrel?
 

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Discussion Starter · #11 ·
20" barrel

I went through everything one more time cleaned and lubed. The gas tube did have more crud then I would expect. Im going to order the one piece gas ring, its silly cheap.

Ill grab some new ammo and hit the range next. I need to try my new FS2000 anyway

Ill report back, thanks for the help everyone

drew
 
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