AR15 Not Feeding, Only Ejects Sometimes

[cascadianliberty2012]

Try removing the hand guards, and realigning the block. If the block came loose, the spring tension on the delta ring could have pushed the whole assembly forward, continuing to partially block the gas port.

And to Happy, we are trying to help. No one is ridiculing him.

Thanks, I'll try that next...

 

[Velzey]

Blow thru the gas key on top of the carrier.. I've popped a primer and had it lodge up in the key thus blocking the flow..

Take your gas block off and make sure the thru hole to the bbl is clear, then make sure the gas block itself is clear... Also make sure the tube is clear...

I cleaned an AR tonight that I swear had 1/32 of carbon build up inside the front of the carrier... And they wondered why the bolt wasn't rotating and locking in place...

 

[fraidenburg]

I have seen problems with offset set screws on the gas block. Make sure they are even. If they are not it will let enough gas out to short cycle the bolt. This is one reason I stay away from them.

 

[RAC123]

It's kind of confusing the way you are trying to describe your situation. Hope this helps a bit.
Feeding issues are usually your magazine.
Extracting issues should be your extractor spring (copper or green?) and insert (black or blue?).
Did you try to load a round into the mag, chamber, fire, and see if the bolt group locks?
Y or N.
Try using another brand/ammo(not enough pressure).
Clean and lubricate.
Make sure gas key is not loose/damaged/screws.
Buy new gas rings. You can check your old one by holding the bolt assembly upside down with the whole carrier assembly intact. If it slips to the lock either you have bad rings or the carrier is out of spec.
Buy a new gas tube. (Built up carbon/worn)
Gas system incorrectly modified.
Aftermarket gas block.
Action spring out of spec.
The list goes on especially piecing an AR with different brand/aftermarket parts.
Just sounds like to me your #1 problem is failure to cycle.

 

[Member 34319]

It's kind of confusing the way you are trying to describe your situation. Hope this helps a bit.
Feeding issues are usually your magazine.
Extracting issues should be your extractor spring (copper or green?) and insert (black or blue?).
Did you try to load a round into the mag, chamber, fire, and see if the bolt group locks?
Y or N.
Try using another brand/ammo(not enough pressure).
Clean and lubricate.
Make sure gas key is not loose/damaged/screws.
Buy new gas rings. You can check your old one by holding the bolt assembly upside down with the whole carrier assembly intact. If it slips to the lock either you have bad rings or the carrier is out of spec.
Buy a new gas tube. (Built up carbon/worn)
Gas system incorrectly modified.
Aftermarket gas block.
Action spring out of spec.
The list goes on especially piecing an AR with different brand/aftermarket parts.
Just sounds like to me your #1 problem is failure to cycle.

RAC123s list is a little extensive.

I think your best bet is like others have also come to conclude.

Start with your gas block. Make sure your gas system is clear, clean, and lubed.

Also if needed PM me I can take a look at it in person if needed.

 

[cooper]

A quick check for short stroking....load 1 round in your magazine...fire...if your bolt catch fails to hold bolt carrier back.......short stroking causes vary Wolff extra power buffer spring ? Carrier leaking ???... clean up your BCG....extend bolt out in BCG.....stand on bolt-face flat surface...your carrier should not collapse under weight if it does replace gas rings......make sure no blockage in gas key.....MY GUESS...leaking gas block ( if you discovered it had came loose ) ...line of sight the block w/upper for straight....make sure roll pin for gas tube-gas block is still there......FIRE SINGLE SHOTS AND CHECK YOUR BRASS.... its like going to a palm reader w/AR rifles............DON'T GIVE UP AND WHEN YOU GET PASSED THIS CAME W GREAT HANDS-ON-GUN REPAIR ....AND ITS RUNNING GIVE THE DIRTY STEEL CASE A SECOND LOOK ( FOR ROCK BLASTING ) Over the last 6yrs I've burned 10,000++223-7.62x39-40S&W-45acp with less than 10-20 crap primers. Which most of the time end up going bang the second time around . I ONLY WISH THAT IT CAME WITH A MAGNET RATHER THAN SPAM KEY . THEY ARE AS BAD AS HULLS AT THE PITTS ......TAKE A RAKE.....HOPE YOU GET TO ENJOY RIFLE SOON...JIMMY

 

[mjbskwim]

Easiest way to check algnment of the gas block is to stick the little tube on the cleaner can it the gas tube at the chamber. ISpray some into the tube,if it doesn't come out in the barrel the block is not aligned
Then make sure your rings on the bolt aren't lined up.

 

[cascadianliberty2012]

UPDATE: I tried everything today and did find the issue, it is actually the bolt hold open lever not having enough tension on it causing it to rise up and slow the bolt down when it cycles. I was actually missing a little pin that sits on top of the spring that is responsible for the tension. Now it will shoot better, but it is still having this issue about 1/3 of the time. What should I do? File the lever, get a new one?

 

[Garg]

PM Reno911. He said he would take a look at it for you.

 

[Member 34319]

UPDATE: I tried everything today and did find the issue, it is actually the bolt hold open lever not having enough tension on it causing it to rise up and slow the bolt down when it cycles. I was actually missing a little pin that sits on top of the spring that is responsible for the tension. Now it will shoot better, but it is still having this issue about 1/3 of the time. What should I do? File the lever, get a new one?

I've never heard of a bolt stop being the culprit to a short stroke issue. Unless you installed it when building the lower incorrectly? I'm not sure how you would tell if the detent was missing since once the ping pong paddle is installed its kind of hard to see the detent and or the spring for that matter. That and that roll pin is the hardest pin to remove on a lower without a special punch.

I'm still betting money on this being a gas issue. If the gun is running yet short stroking. It's not getting enough gas.

Hit me up if it still gives you hell.

 

[Doc In UPlace]

Sounds like a gas leak to me too.

Bolt release has about 0% to do with proper cycling other than staying out of the way and NOT catching the bolt when it shouldn't.

The rifle will run completely fine without it on there at all. Is the bolt carrier key tight and properly staked (?)

 

[cascadianliberty2012]

Sounds like a gas leak to me too.

Bolt release has about 0% to do with proper cycling other than staying out of the way and NOT catching the bolt when it shouldn't.

The rifle will run completely fine without it on there at all. Is the bolt carrier key tight and properly staked (?)

Although I would agree with you, what I've encountered suggests otherwise. The paddle has some horizontal play, but has more tension on it now so it doesn't bounce around, just wiggles left and right. When I shot it while holding the bolt release, it never had any issues. I think it sometimes is sticking up slightly, causing the bolt to lose some velocity.

 

[Doc In UPlace]

IMO if the power ratio is that tenuous so that a couple foot-ounces of pressure on the bolt release is making any difference, then the problem is elsewhere. From this description that bolt is not unlocking right and by the time it gets unlocked the recoil energy is mostly gone.

The improper bolt release installation may not be helping any, but that's not your cause. That carrier group should be flying back hard enough to push you backward a little bit, and unless it's binding hard enough to score lines in the carrier (?) that dinky bolt release spring just doesn't have enough pressure.

Look at how huge your buffer spring is, and THAT doesn't stop the bolt from compressing it all the way to the rear when cycling normally.

Speaking of which, how is the buffer spring and buffer? Are they performing to spec and not hanging up?

 

[Member 34319]

Although I would agree with you, what I've encountered suggests otherwise. The paddle has some horizontal play, but has more tension on it now so it doesn't bounce around, just wiggles left and right. When I shot it while holding the bolt release, it never had any issues. I think it sometimes is sticking up slightly, causing the bolt to lose some velocity.

It's likely not.

Go back to my other post. There are usually 3 culprits. Weak ammo. Too heavy of a buffer. Or a gas system issue. I have only ran into one other issue once and that was because he bought a really cheap BCG off the Internet and the bolt was undersized and off spec. Every other AR15 I have worked on was short stroking because of one of those three reasons. Usually the 1st or second reason. However the 3rd reason happened just as often.

If you put this rifle together using standard decent quality components, you should be in the clear, and the bolt catch should not be any sort of issue

The bolt catch does move left to right, and should have good spring tension pushing it down. The mag follower will use its spring to bypass that tension and push the catch up, stopping the bolt.

Even if it is the reason and scraping the carrier as the rifle cycles, this would have to be so tight that there would likely be gouging in the carrier as an affect. That and if your rifle did manage to fully cycle it would be catching the bolt on every full battery. Stopping function after each round fired.

PM me. I don't mind helping you out with this. I've built and worked on many AR15s.

 

[cascadianliberty2012]

It's likely not.

Go back to my other post. There are usually 3 culprits. Weak ammo. Too heavy of a buffer. Or a gas system issue. I have only ran into one other issue once and that was because he bought a really cheap BCG off the Internet and the bolt was undersized and off spec. Every other AR15 I have worked on was short stroking because of one of those three reasons. Usually the 1st or second reason. However the 3rd reason happened just as often.

If you put this rifle together using standard decent quality components, you should be in the clear, and the bolt catch should not be any sort of issue

The bolt catch does move left to right, and should have good spring tension pushing it down. The mag follower will use its spring to bypass that tension and push the catch up, stopping the bolt.

Even if it is the reason and scraping the carrier as the rifle cycles, this would have to be so tight that there would likely be gouging in the carrier as an affect. That and if your rifle did manage to fully cycle it would be catching the bolt on every full battery. Stopping function after each round fired.

PM me. I don't mind helping you out with this. I've built and worked on many AR15s.

I took the gun to Curt's yesterday as that's where I've gotten the majority of the parts for my build. They found nothing wrong with the BCG (Spike's) or the gas system upon a quick inspection. The bolt catch flapping around caught their attention though a lot and they told me that even a 5% reduction in cycling velocity could cause the issue I'm having. I got the new detent and spring, shot it, and didn't have an issue until after about 5 rounds or so then it happened again after a few more. Once I started physically holding the bolt release while shooting, it never happened again. I ran out of time yesterday so I'll do a couple more things this week to troubleshoot it. If I still don't get it completely sorted out, I'll seek out your expertise in person. Again, I really appreciate the help and willingness.

 

[mjbskwim]

Sooooo the catch is out of specs and you need to change it? 20 bucks?

 

[Member 34319]

Definitely a professional at this point. Removing a roll pin on the bolt catch is a PITA.

If you want to go shoot together with a donor lower let me know. That should be the true test.

 

[Toxic6]

I'm going with the consensus of causal symptoms...his gas impingement system isn't timed right or getting full strength/has a blockage, his recoil spring or buffer are too heavy, or one I think could be a cause also...did he get the barrel torqued down and head-spaced correctly on assembly? Could be getting a loss of gas and binding up in that area too.

 

[cascadianliberty2012]

I filed down a very small amount of my bolt catch today, and then tested it with a full magazine. I dumped all 30 rounds without a single hiccup. I didn't make any new gas block adjustments or anything. I guess the Curt's gunsmith was right... it was the floppy bolt catch.

Thanks a lot for the responses and help, everyone!

 

[Member 34319]

I filed down a very small amount of my bolt catch today, and then tested it with a full magazine. I dumped all 30 rounds without a single hiccup. I didn't make any new gas block adjustments or anything. I guess the Curt's gunsmith was right... it was the floppy bolt catch.

Thanks a lot for the responses and help, everyone!

I'm adding this one to my books. Never had a bolt catch cause cycling issues before. Goes to show how annoying ARs can be when they don't cycle.