AR Not Cycling

JCV

JCV

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I still have less than 500 rounds through the gun. Today about 50 shots in it wouldn't cycle more than one round. Id have to keep manually cycling the next round, not fun.
Any ideas on what it could be?
I just shot it Sunday and this happened a few times but I figured it was the old ass mag not feeding right. That wasn't the case today though.
 
What stage is the failure? Ejecting spent case? Feeding fresh round? Check the ejector on the BCG to make sure it's within spec still. Do you have crap on the feed ramps?
 
Sorry, it's not feeding the next round. Ejecting fine.
First round loads, fires, ejects case bolt locks forward but there is no round in the chamber. Pull the trigger click, obv nO boom because there is no round in the chamber. Pull the chargin handle back and release it to feed the next round and it fires fine, then it happens all over again.

Is that enough info? This is my first build so I'm not too familiar with everything yet.
The gun was cleaned a few hours before heading to the range today.
 
sounds like what they call 'short stroking'

the bolt moves back enough to extract and eject the spent case, but not far enough to strip the next round from the magazine.

post your rifle's specs. barrel length, gas system, buffer, ect
 
SJan said:
sounds like what they call 'short stroking'

the bolt moves back enough to extract and eject the spent case, but not far enough to strip the next round from the magazine.

post your rifle's specs. barrel length, gas system, buffer, ect
Click to expand...

that definitely sounds to be the issue. I've heard people at the range say this but never gave a shit to look it up
 
Well since I helped with the build I should chime in..


Did you undo the gas block and put lock tight on the gas block set screws like I said you should? Maybe it shifted and causing a restriction ?
 
gas block and set screws do not belong in the same sentence

If this is the case, the gas block placement over the barrel gas port should be verified, and dimples should be drilled into the barrel for the set screws to bite into. Use a whole bottle of green lock-tite on that bitch
 
SJan said:
sounds like what they call 'short stroking'

the bolt moves back enough to extract and eject the spent case, but not far enough to strip the next round from the magazine.

post your rifle's specs. barrel length, gas system, buffer, ect
Click to expand...

14.5" barrel
mid length gas system
A2 length buffer tube


warwickben said:
Well since I helped with the build I should chime in..


Did you undo the gas block and put lock tight on the gas block set screws like I said you should? Maybe it shifted and causing a restriction ?
Click to expand...

i didn't. maybe this is it. i would forget something retarded like that.
 
Last edited by a moderator:
What ammo were you using?

with a mid length paired with a shorter barrel paired with a heavier a2 rifle buffer might be enough to cause a short stroke with weaker ammo.
 
mikem317 said:
Did you try a different magazine?
Click to expand...

Yeah, this was my first thought since most of my mags are preban with original springs and followers, but I have some 10 round pmags and it was doing the same thing, so i doubt it's the mags.

Shot a few hundred rounds sunday and it was fine besides a few hiccups.
Shot about 50 yesterday before it started acting up, so it's most likely the gas block like people are sugesting.
 
I had a failure to feed issue with my newly assembled AR because I didn't "Lubricate" the rifle well enough. That may be the culprit as it solved my problem.
 
Hey JCV, Was it the Herters that wasn't cycling? I bought a couple of boxes of that from Cabellas and it was short stroking my AR. Everything else worked fine.
 
Herters isn't great ammo, I have a Colt 6920 that chokes on any steel cased ammo. The same gun runs like a champ with quality Brass cased ammo. My gun that choked with Herters and wolf ran flawless with Asyum Ammo and Federal green tip. At Colt armorers school they dissuaded using Steel cased ammo . They staed the ammo is underpowered and likely to cause malfunctions .YMMV. My gun that choked with the steel cased ammo was short stroking.
 
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stinx said:
Herters isn't great ammo, I have a Colt 6920 that chokes on any steel cased ammo. The same gun runs like a champ with quality Brass cased ammo. My gun that choked with Herters and wolf ran flawless with Asyum Ammo and Federal green tip. AT Colt armores school they dissuaded using Steel cased ammo.YMMV
Click to expand...
This, and I think it is a little underpowered. Wolf shoots ok, Tula wont cycle or gets cases stuck. All brass cycles great.
 
I had this exact issue shortly after buying my AR. Turns out it was a loose front gas block that began to inch forward after a few shots, causing misalignment between the hole in the barrel and gas block, hence restricted/no gas flow, short cycle, would eject but not feed.

I too have an A2 front sight held in place with two measly set screws, which by far is the most inane mechanical attachment conceived for this part of the firearm, and don't gimme any "need to adjust front windage" excuse. Of course this was my first AR and I didn't know any better. I don't really want to dimple my barrel, and I don't want to clean up a Loctite mess anytime I need to move the front sight. White Oak cuts big notches in their barrel for front sight attachment and windage adjustment, but those are bull barrels, not a NATO profile like I have. My 20" barrel does not have the notches for the pins either.

To make matters worse I live in MA so my compensator has been firmly attached; safe, blemish-free disassembly to fix this is likely going to involve a machine shop and possibly the demise of my current compensator.

Until I decide to tear this apart to fix this, I have resorted to installing a $5 black oxide two-piece machined steel collar around the barrel, directly ahead of the front sight and pushed against the sight tightly. The collar has two hex cap screws, clamps down ultra hard and will not budge, hence the sight doesn't either. Problem solved and the rifle cycles perfectly. It was a cheap fix but outside of a layman anyone who sees it will say "wtf?" Actually it doesn't look that bad. A permanent fix will be done sometime in the future.

Sorry to hijack, but I had the same issue and it vexed me to understand why the front sight was installed so poorly. To be fair the rifle builder did offer to help fix it.
 
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A mid length gas system, 14.5" barrel, a2 rifle buffer and underpowered ammo is probably where it's going wrong. I would say either use hotter ammo or if u are willing, switch to a M4 style buffer extension and use a CAR buffer for underpowered ammo.

Sent from my DROID4 using Tapatalk 2
 
Da_lucche said:
A mid length gas system, 14.5" barrel, a2 rifle buffer and underpowered ammo is probably where it's going wrong. I would say either use hotter ammo or if u are willing, switch to a M4 style buffer extension and use a CAR buffer for underpowered ammo.

Sent from my DROID4 using Tapatalk 2
Click to expand...

My BCM 14.5" middy will cycle Tula. FA BCG and a carbine buffer.
 
A progressive failure is usually caused by something that came loose and is out of alignment. There aren't many parts that can do this, Gas Key, gas block are a good place to start
 

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