AR15 --- fired 5.56 round stuck in chamber

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pummumu

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Hi all,

I was firing my newly assembled 11.5" barrel AR15 yesterday and encountered extraction issue.

I bought the barrel that has description saying it accepts 5.56 nato and .223 round, however, when I fired 5.56s, the empty cartridge kept getting stuck in the chamber.
.223 was shooting without a problem.

Can anyone please shed some light into this issue? This is my very first completly build from scratch rifle.
Did the store write the wrong description or something else might cause the issue? There is no marking on the barrel unfortunately.


My spec:
- Carbine length gas tube
- H2 buffer
- 11.5" barrel


thanks in advanced,
H
 
What kind of barrel? Adjustable gas tube? When you mean stuck is the case partly thru the Ejection port and the bolt has moved or are you having to pull the charging handle back because the bolt has not moved?
 
Dr. Hunter said:
What kind of barrel? Adjustable gas tube? When you mean stuck is the case partly thru the Ejection port and the bolt has moved or are you having to pull the charging handle back because the bolt has not moved?
Click to expand...

It's the TNA brand 11.5" barrel. Non adjustable gas tube.
And I had to pull charging handle back because the bolt hadnt move. When I forced pull the charging handle, the extractor damaged the the rim. I had to jam a rod down the barrel to get the empty cartridge out.
 
What brand ammo was the "5.56"?

You say you had no issues with the ".223" ammo. What brand? where were those cases ejecting?
 
*MALICE* said:
What brand ammo was the "5.56"?

You say you had no issues with the ".223" ammo. What brand? where were those cases ejecting?
Click to expand...

The 5.56 was federal independence. The .223 was mixed between PMC and Federal ( no issue on either brand .223)
The .223 ejecting without any issue.
 
I knew you were going to say Independence for the 5.56 ammo ;)

What direction (1 oclock, 3 oclock, 5 oclock) is the .223 ammo ejecting? (assuming 12oclock is the direction the barrel is facing)
 
*MALICE* said:
I knew you were going to say Independence for the 5.56 ammo ;)

What direction (1 oclock, 3 oclock, 5 oclock) is the .223 ammo ejecting? (assuming 12oclock is the direction the barrel is facing)
Click to expand...

LOL, yeah, it was the cheapest one :)
Sorry, I didnt pay attention to the direction., It was indoor range, so the ammo very quickly bounced off the divider wall.
 
pummumu said:
LOL, yeah, it was the cheapest one :)
Sorry, I didnt pay attention to the direction., It was indoor range, so the ammo very quickly bounced off the divider wall.
Click to expand...

I was just trying to get an idea if your barrel was really overgassed with the "223". If it was/is, then you probably have an overgassed barrel which is what's causing the problem with the Independence ammo (which tends to be REALLY hot and somewhat inconsistent).

easiest solution is don't run independent ;)
 
*MALICE* said:
I was just trying to get an idea if your barrel was really overgassed with the "223". If it was/is, then you probably have an overgassed barrel which is what's causing the problem with the Independence ammo (which tends to be REALLY hot and somewhat inconsistent).

easiest solution is don't run independent ;)
Click to expand...

I am using this barrel:
https://truenortharms.com/ar15_defa...rrel-with-front-sight-post-fsb-5-56-nato.html


It did mushroomed my buffer rubber when I used the Carbine weight, then I switched to H2. H2 buffer rubber looked fine after 150 rounds. the Carbine one was destroyed only after 80 rounds before.

When you said dont run independent, in your experience, would it run with a better brand?
]edit: I forgot that I did try 3 rounds of 5.56 Xtac PMC, it had the same issue unfortunately.
 
Well, assuming you have an TNA/CNA buffer......there have been some reports of their buffers not being very good quality (so the rubber bumper being mushroomed may or may not be a symptom over severe overgassing), but.....that's not really your main problem imo


I'm not fond of using heavier buffers to counteract overgassed barrels. A lot of people do it, but in my experience, if your barrel is so overgassed that you're having serious problems, a heavier buffer often won't fix it. I find buffer weight makes more of a difference on guns that are gassed correcly, or slightly overgassed. I'm sure others may disagree with me.

So, your barrel is probably overgassed, and an adjustable gas block could help (it definitley won't hurt anything). You could also have a slightly rough chamber that is causing issues with higher pressure ammo......but it's hard to diagnose over the interweb.

I'd use American Eagle if it's an option. It's not match grade ammo by any means but it doesn't seem like you're shooting any precision rifle matches with that gun any time soon ;)

Also, just curious, are the cases not being extracted from the chamber at all? Or are they getting the rim ripped off and then the carrier is closing back against the fired case? If the rims are being ripped off, it's possible you need a new extractor spring OR a donut/oring around your extractor spring (assuming you don't have one already)
 
The cases arent extracted at all. The rim ripped from me pulling the charging handle hard manually.

You are correct on the carbine buffer, it was TNA brand, but my H2 was S&J brand.

Educate me on this please, if the barrel overgassed, wont that makes the bcg pushed back and violently extract the cartridges?
Can't use adjustable gas block as this is for my clone rifle :(
 
I saw this once at PoCo. Chamber reamer must have broken on way out, leaving a groove which nicely anchored the fired cases. I'll bet your chamber is out of spec.
 
bross said:
I saw this once at PoCo. Chamber reamer must have broken on way out, leaving a groove which nicely anchored the fired cases. I'll bet your chamber is out of spec.
Click to expand...

Thats my fear as well :(
Might have to end up sticking to .223 with this rifle
 
YES - AVOID INDEPENDENCE AMMO!! I bought two boxes only shot one and will never touch that ####e again!! Good price but not worth destroying your firearm over. I had at least half have the primers blow out....ran other ammo and no issues (just like the previous 5 years shooting the AR). I contacted my local and they said they would exchange the 2nd box of ammo for another brand which was nice of them.
 
My new build had the same issue. Case stuck in chamber, extractor tore off part of the case rim.

How well did you clean your barrel/chamber? Get a AR chamber brush and give it a good scrubbing. Didn't need anything rough,I just used g96 3 in 1.

And that was on a $300 faxon barrel. But there was something in the chamber causing friction and jamming up cases. Wasn't visible to the eye.
 
Once fired the soft shell casing is fire formed to chambers, any tiny grooves and ridges on a rough chamber wall acts like the threads of a screw holding the shell casing firmly in the chamber.

Depends on how rough the chamber wall is, a stiffer exacter spring might over come the extra friction or have a gunsmith polish the chamber.
 
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