Any update on the troubleshooting?
I “upgraded” to a LMT enhanced bolt in one of my rifles and started getting the same malfunction you’re experiencing. I “downgraded” back to the Sionics bolt and the malfunction went away. I tried the bolt in 2 other rifles and they did the same thing. Now I have a $200 superdupermalfunctioninducinghunkofshitthatsitsinthepartspile. Lol.
It’s pretty though.
Last edited by Jsp10477; 02-24-20 at 19:10.
“I prefer dangerous freedom over peaceful slavery.” – Thomas Jefferson.
Update:
No failures through several hundred rounds today. Only change was pistol grip tightened and back to H2 buffer. Loose grip was for sure causing the issue.
Nope. I've been there done that with it no problems in the past. And the malfunction didn't appear to be action related, it appeared to be mag related. It starts malfunctioning every mag when the grip is loose, then goes away when the grip is tight? Hmm... best we were able to figure is that with a loose grip and the added back pressure of the suppressor, the gun was physically shifting rearward forcefully enough to jar the round from the mag loose, which then caused the bolt to hang up on it when the next round was attempting to feed. Now with a perfect shoulder purchase, perhaps the gun doesnt malfunction because recoil is then independent of the grip. However when testing the gun with what rounds I had left last trip I wasnt focusing on it, so only way to test would be loosen the grip again. I'll pass on that since I've applied loctite. Not even a shadow of a doubt in my mind that the grip was the issue.
Wow. Sounds like the gun is on the ragged edge of reliability. I always verify function with no shoulder purchase to ensure the gun works no matter how it's being fired.
I sometimes use a couple wraps of teflon tape on the grip screw to make sure they stay tight.
No it works fine not shouldered when the grip is properly secured, because the pistol grips allows you to absorb that recoil. Again, it's not an action problem, it's a magazine problem. The only contributing factor from the rifle is a loose grip. With nothing to stop or absorb the recoil (loose grip AND poor shoulder weld) the magazine is jolted and spits the front of the round upward. The same as when someone inserts a full magazine on an open bolt hard enough to dislodge a round. This rifle has run thousands of rounds in varying condition (-10F and ice to 100F and rain) with sparse cleaning. It's far from the ragged edge orf reliability, which is why my ejection patterns never changed even when the malfunctions occurred.
I tried to replicate this with a bone stock 6920, NHMTG 30 round mag w/Magpul follower, M855 ammo.
I held the gun with no contact with the grip, pulled the trigger with my thumb so that there was as close to nothing as I could get to counteract the recoil.
All 30 rounds ejected with the same pattern and distance as when firmly shouldered, bolt locked back on empty.
I loosened the grip screw 5 turns and repeated the first test, then shot another mag of double taps, various positions. Same ejection and lock back as the first two mags.
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