I doubt it's the buffer, I run an upper very similar and use an H2. My thoughts are it could be the recoil spring, the extractor or extractor spring.
Edit: listen to that guy^^^^ first
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I doubt it's the buffer, I run an upper very similar and use an H2. My thoughts are it could be the recoil spring, the extractor or extractor spring.
Edit: listen to that guy^^^^ first
Yeah, sorry I don't know all of that, it's not my gun. He's a member here, so maybe he'll post. The more I think about it I'm thinking it might be an ejector issue?
1. How many rounds through this upper to include the BCG? - I think probably less than 500.
2. Has it malfunctioned before? - No, based on his reaction, but he said he just changed the buffer, so that's why he was thinking that was the issue.
3. Did you try other ammo? - Yes, but it was PMC Hot Shot. Actually, that's what we were using when it started. Thinking it might be ammo related, I broke out the Federal and it did the same thing.
We tried multiple Pmags (3 or 4) as well. He thought the gun might just be dry at first. He lubed it with Slip2000 and it did the same thing.
Now, offset all of this with the fact that my DD gun was 100% with the same mags and ammo. It's 16" mid-gassed with an H2 buffer, so that should be borderline reliable based on what I've read, but between a Vickers class and various other range outings adding to 1200 or so rounds, not a single malfunction.
The more I think about it, I wish we'd swapped BCG's to see if that fixed it. That brings another side question. Back in the day, I was told that swapping bolts between barrels was a bad idea due to lug/barrel extension wear patterns. Truth or myth?
I'm telling you man, the Vltor A5 turned my LMT 10.5" into an ammo eater and it will eat anything, suppressed or not, and it feels very consistent. It was always reliable, but you could tell what it liked and didn't like. Now, it likes everything.
Before that, I ran an H2. It cycled fine with an H as well, but the H2 seemed to work a little better. My focus isn't on how the gun feels when shooting as much as how consistent it is.
This isn't directed at your buddy, but some people don't realize that how reliable it is and how good it feels on the shoulder don't always go hand in hand.
If the A5 is not an option, I'd stick with a standard action spring and an whatever buffer used to work. Was it an H buffer he had in there or an H3 since you said the H2 was being used when he encountered issues?
I would replace the ejector spring first (cheapest item) and then try again. If it still has issues then I would go back to an H buffer.
Yeah, definitely check the ejector. Out of curiosity, was the empty case held in place by the extractor or was it free from the bolt like the second round? When this would happen, did you guys simply work the charging handle and eject the spent case?
Also, did you notice it running strong or was it feeling sluggish in any way? The H2 should run perfectly fine in most 10.5" rifles.
Well, a quick update. We got out to shoot again yesterday and KP was running the H buffer instead of the H2. The gun ran without a hitch. Thanks again for the thoughts and input!