ar10 not ejecting

[Nickweis]

I have a 260 rem on an AR10 platform which will not eject the spent casings. I have taken apart and cleaned the bolt head an even replaced the ejector pin and spring but that did not help. after I have finished shooting a mag the bolt will lock back so I'm not sure what is up, my next thought would be a gas issue but I'm not sure how I would approach that. help

 

[EWaugh]

I have a 260 rem on an AR10 platform which will not eject the spent casings. I have taken apart and cleaned the bolt head an even replaced the ejector pin and spring but that did not help. after I have finished shooting a mag the bolt will lock back so I'm not sure what is up, my next thought would be a gas issue but I'm not sure how I would approach that. help

Have you checked the 3 gas rings to make sure they are spaced equally apart from one to the other.

 

[Nickweis]

I just went and looked and my gas ring is just one big contentious one?

 

[mac86951]

PM sent

 

[johnfred1965]

With the bolt out of the gun, can you insert and remove a shell from the bolt? Maybe a burr in the bolt head or plunger sticking? Or are your loads hot enough to expand the head in the bolt? Just some guesses to check out. Had trouble with mine short stroking, but you already have that figured out.

 

[Michael C]

So, there are two issues. 1. Ejection: When you fire where does the brass go? Does it stay in the chamber or sitting on top of the mag? 2. Bolt not locking back: It may be a buffer spring issue, or a bolt catch spring issue. Both are cheap parts.
Is this a new issue/did it used to eject fine and now it does not? What did you change...powders bullets ect.

 

[msalm]

Check your extractor and see if the case just ahead of the extractor groove isn't levering the head out of the bolt face. You may have to stone more of an angle on the extractor face...just one thought.

 

[Raptor]

Did you build this or is it a factory build?? You may have a gas block that is not correctly installed and blocking part of the hole in the barrel and not letting the bolt blow back to the rear and eject the case. Just a thought....

 

[mic2377]

If it is locking back, it has sufficient gas to operate the action. I would go looking at the extractor specifically. What bolt carrier and bolt do you have, and what pattern? (ie AR-10 or DPMS/SR-25)

I had a 308 AR where I experienced similar issues. It was related to an extractor with TOO much tension, which would not release the brass for ejection. It turns out that the bolt in question (from a DPMS-pattern CMMG MK3) had extra O-rings under the extractor, in addition to dual springs. Removable of the O-rings, ensuring the extractor rotated freely on its pin, and knocking off a few of the extractor's sharp edges cured the problem and resulted in consistent ejection/extraction.

 

[Nickweis]

If it is locking back, it has sufficient gas to operate the action. I would go looking at the extractor specifically. What bolt carrier and bolt do you have, and what pattern? (ie AR-10 or DPMS/SR-25)

I had a 308 AR where I experienced similar issues. It was related to an extractor with TOO much tension, which would not release the brass for ejection. It turns out that the bolt in question (from a DPMS-pattern CMMG MK3) had extra O-rings under the extractor, in addition to dual springs. Removable of the O-rings, ensuring the extractor rotated freely on its pin, and knocking off a few of the extractor's sharp edges cured the problem and resulted in consistent ejection/extraction.

I dont know which of the top of my head, this rifle was a grautation gift. I do belive it does have an O-ring in the extractor though. I will try removing that.

 

[jonbearman]

With the o-ring installed the extractor should be very stiff to move with your fingers. Mine did it but after I sent the bolt back to armalite under warranty they updated it with an o-ring and new style extractor and spring.

 

[Nickweis]

I took into my gunsmith and he took a look at it. And we realized that my buffer spring a 24.5lb pull on it when all of the ones he had a 18.5lb pull and mine also had a substantial amount of more coils and he was pretty sure that is the problem. He said try snipping 1 or 2 coils of and see if it helps and of not being it back in.

 

[waldo1979]

I just went and looked and my gas ring is just one big contentious one?

That's a McFarland gas ring. FYI, alignment of the gas rings mattering is a fallacy.

 

[hogan]

Have you tried different ammunition?
If shooting handloads, realize that none of the AR builders warrant their rifles with handloaded ammunition.

How did the overly long recoil spring get into your buffer tube? Do you have a rifle or carbine buffer? Don't think you remarked which rifle you own, or which barrel length. Try some generic .308 ammo like American Eagle or Winchester USA; just cheap ball ammo; but fresh, no surplus stuff from 30yrs ago. See if you get decent ejection.

Not like you have reassembled the bolt upside down is it? Extractor positioned correctly in carrier? Does the rifle eject a dummy round when have one chambered and rack the bolt back? Carbine spring and buffer in a rifle might be your problem...

 

[ND shooter]

Have you tried different ammunition?
If shooting handloads, realize that none of the AR builders warrant their rifles with handloaded ammunition.

How did the overly long recoil spring get into your buffer tube? Do you have a rifle or carbine buffer? Don't think you remarked which rifle you own, or which barrel length. Try some generic .308 ammo like American Eagle or Winchester USA; just cheap ball ammo; but fresh, no surplus stuff from 30yrs ago. See if you get decent ejection.

Not like you have reassembled the bolt upside down is it? Extractor positioned correctly in carrier? Does the rifle eject a dummy round when have one chambered and rack the bolt back? Carbine spring and buffer in a rifle might be your problem...

Op said its a 260. Do not try 308 ammo!!! Repeat!! Even if bolt will/would close on 308 DO not shoot!! I'm sure you know this, but just pointing out.

 

[mac86951]

Any update? Did recoil spring help?