Gas rings worn out? (Issue Resolved)

[jakhamr81]

I think I know the answer but want to see what some others say.

I have an AR that ran flawlessly for over 1,000 rounds and just started short stroking after about 40 rounds at the range today. The Carrier key seems solid. When I remove the bolt from the carrier it seems pretty loose. When I hold the carrier with the bolt opening up and insert the bolt it just drops all the way to the bottom without any resistance. It feels a lot like when I had a piston gun that had no gas rings.

So this leads me to think that the gas rings may be worn out. Is there anything else to check?

 

[chongoMT]

Re: Gas rings worn out?

It sounds like gas rings. Another thing is extend the bolt all the way out of the carrier and place it vertically on a flat surface, if it doesn't support its own weight its usually a good time to change rings. Hope this helps.

 

[jakhamr81]

Re: Gas rings worn out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chongoMT</div><div class="ubbcode-body"> ...Another thing is extend the bolt all the way out of the carrier and place it vertically on a flat surface, if it doesn't support its own weight its usually a good time to change rings. Hope this helps.</div></div>

That's a definite NO! The bolt will also fall out when held upside down with just a very slight shake.

 

[BBJones13]

Re: Gas rings worn out?

Weird they completely wore out after 1000 rounds. should go closer to 10 times that.

 

[jakhamr81]

Re: Gas rings worn out?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BBJones</div><div class="ubbcode-body">Weird they completely wore out after 1000 rounds. should go closer to 10 times that.</div></div> I've never had a set wear out. I shot suppressed about 80-90% of the time; do you think that may have accelerated the wear?

 

[DMack]

Re: Gas rings worn out?

I have legitimately over 20k through my Smith M&P-15. Still running the original gas rings. The two tests mentioned... My bolt fails miserably. But this rifle runs flawlessly. I've never worn out a set of rings. Never seen it happen either...

What kind of gas block do you have?

 

[lethal93ta]

Re: Gas rings worn out?

I have over 10k rounds out of my JP AR mine are still fine, I did change them out when I built it to the McFarland 1-Piece style ring instead of the 3 rings I just like the fact I dont have to play with rings to get them staggered around the bolt.

 

[GUNNER75]

Re: Gas rings worn out?

Double check your carrier key bolts. I had one that I thought it was rings and swapped a couple sets around. One set loose as a goose, the next tight as can be. A little difference, but still gave me issues. The key was staked well, and the bolts were tight but guessing they were not torqued enough from the factory or they stretched (can't see this, but I shot the heck out of it suppressed and hot several times).

I cranked on the key bolts a bit more and they had about 1/16" of a turn in them. Problem fixed. I restaked my key and no problem since.

 

[DMack]

Re: Gas rings worn out?

Lethal... I will tell you... I was trained to always stagger the rings and I understand the logic behind it. But, I have demonstrated to my classes that my rifle can and will run with three, two and even just one ring. Staggering the rings is not as important as once thought. It's not even taught any longer.

 

[DMack]

Re: Gas rings worn out?

Gunner... I was about to suggest checking the gas key... So plus one on that.

 

[jakhamr81]

Re: Gas rings worn out?

Carrier key is fine; screws are still tight and staked.

 

[johnson]

Re: Gas rings worn out?

Test with a known working bolt.

 

[msalm]

Re: Gas rings worn out?

When you clean the rifle do you clean out the buffer tube? Make sure it is clean, lightly oiled, and there's nothing pluging the hole through the buttstock screw.

 

[jakhamr81]

Re: Gas rings worn out?

I just broke down the gun and was able to ID the problem. It seems that the gas tube roll pin some how came out and the gas tube was allowed to free float. Luckily I keep a bunch of spare parts around for things like this. I'll back at the range in the morning.