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lernerk392
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Is there a direct way to test this out to verify its the issue?
The weirdest thing happened to me the other day...
- Thread starter lernerk392
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Will the bolt lock back if you cycle it by hand on an empty mag? If yes it is usually either a power issue with the ammo or a gas issue. Check to see if the gas block has moved. another thing I just thought of have you tried cleaning the buffer and buffer spring? It may have grease on it and get sticky when cold.
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lernerk392
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It does lock back on an empty mag when hand cycled. Doesn't look like the gas block has moved at all, it's still right up against the barrel *journal [edit, didn't know exactly what it was called]
45/30-06OKIE
Member
Uhh you could take the gas tube/block assembly off and cover the gas block hole and blow into the gas tube and see if it leaks that way.
45/30-06OKIE
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Oh a free tip is that sometimes you have to set a gap of .025in at the barrel shoulder. A finger nail is about that size if you dont have a feeler gauge.
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lernerk392
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Another range report. A lot to say so I'm going to summarize.
Range Report:
Fired 120 rds of the PMC Bronze (First 50rds+ were fired without issue), 60 rounds of the Monarch.
4 total FTFs with the PMC Bronze, several failures to lock back.
No failures with the Monarch (FTFs or failure to lock backs).
This hints at an ammo issue as I used the same mag for all 180rd.
BUT My ejection pattern DEFINITELY hints at a short-cycling issue as the brass was behind the bay of the other guys to my right.
AND
Did another gas ring check, and now it does "collapse" under the weight of the bolt carrier. It did not before, but now it does.
I put the bolt in another Bolt carrier and it DOES NOT collapse under the weight of that one. This bolt carrier is a little lighter than the stock one.
Again, I'm fairly new so I have no idea whats going on here anymore. I'm confused
Could I just swap the whole BCG?
Thanks to anyone still hanging around and has the patience to deal with me
Range Report:
Fired 120 rds of the PMC Bronze (First 50rds+ were fired without issue), 60 rounds of the Monarch.
4 total FTFs with the PMC Bronze, several failures to lock back.
No failures with the Monarch (FTFs or failure to lock backs).
This hints at an ammo issue as I used the same mag for all 180rd.
BUT My ejection pattern DEFINITELY hints at a short-cycling issue as the brass was behind the bay of the other guys to my right.
AND
Did another gas ring check, and now it does "collapse" under the weight of the bolt carrier. It did not before, but now it does.
I put the bolt in another Bolt carrier and it DOES NOT collapse under the weight of that one. This bolt carrier is a little lighter than the stock one.
Again, I'm fairly new so I have no idea whats going on here anymore. I'm confused
Could I just swap the whole BCG?
Thanks to anyone still hanging around and has the patience to deal with me
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45/30-06OKIE
Member
Ok, what exactly have you swapped out again? If you have done multiple things at once that doesn't tell you what the problem is... I do find it odd that the gas rings on the (I assume original?) bolt is all of a sudden not supporting the bolt carrier. As a tidbit, JP Enterprises bolts will fail this test but will function perfectly fine. The way they make the one piece gas ring is wierd.
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lernerk392
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Nothings been swapped at this point. Gun has only been fired stock. I took the stock bolt out of the BCG and put it into another bolt carrier to see if it collapsed under that one too; it didn't. So the gas rings can support one bolt carrier, but not the other (stock one). The switch was only for the test, never fired that way. I have heard that ARs can function without any gas rings at all, so I'm not entirely sure if this is the issue. But it is a new development. ** and yes it is odd, because I definitely tested it before.
45/30-06OKIE
Member
Hmmm... I'd try that other bolt carrier with the original bolt in it (the combo that supports itself) and see if the PMC stuff still gives you problems. If it doesn't then you have a defective bolt carrier and/or bolt possibly. Was this gun still under factory warranty or was this a parts and pieces build?
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lernerk392
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Still under warranty. I didn't think about that! Would like to be able to tell them what's wrong, though, if I can figure it out. I will swap the carrier and shoot some more of the PMC.
45/30-06OKIE
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Sounds good! May I ask what brand the rifle is?
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lernerk392
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I will admit, it is a PSA
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lernerk392
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I've done a little more research and it seems the "correct" way to test your gas rings is to disassemble the BCG until its just the bolt and the carrier and then hold it upside down to see if the bolt drops out. It doesn't just drop out from gravity itself BUT if I give it a jolt it does fly out. The whole assembly seems a little loosey goosey to begin with. Is probably on the upper-bound of spec tolerances. Could be an oversized bolt bore.
Now, if it's my gas rings, what could cause gas rings to wear out so quickly? This bolt has less than 600rds on it.
Now, if it's my gas rings, what could cause gas rings to wear out so quickly? This bolt has less than 600rds on it.
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45/30-06OKIE
Member
I'd just get a new Nickel Boron Toolcraft BCG for 79 bucks from Palmetto and see how that does. If that still doesn't fix it then I'd send it in with a detailed description of your issues. You could probably screenshot your posts on here and print them off.
Edit: At least you buy factory complete rifles so you can send it back if it has a problem that isn't easily fixed by a simple fix. See, I buy parts and pieces and put stuff together that is cheaper than factory like my 24in 223Wylde bull Upper I put together and made a thread about. I saved a bit over 100 bucks over a Rock River upper of the same style. But my frustrations with handguard fitment (had to return my Quad Rail and go with M-LOK) is probably worth at least that much lol...
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lernerk392
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You just read my mind. Typed up a customer service ticket, just in case. I am also looking at other BCGs at the moment. If it turns out that the Palmetto BCG is out of spec, I would still want them to make it right. Either send me a new one or something. I did a quick measurement of the bolt bore and it seems to be about .15mm wider than the other BCG I have. I know that there’s a range of tolerances, so I’ll do some research to see if it’s still technically within spec before I send off a ticket to PSA.
45/30-06OKIE
Member
Huh interesting... .15mm is a lot of room for 50k PSI of hot gasses to escape! That could be why when you are running "hot" high quality 5.56 ammo it runs fine but with basic ammo it short cycles. I recently dealt with an out of spec gas tube in an AR10 and it would do the exact same thing where it would have random malfunctions.
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lernerk392
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In the case that I'm being a dumbass here are the measurements: 13.42mm to 13.45mm for the BCG 1, and 13.55mm to 13.57mm for BCG 2. That's using calipers, so not the best suited tool for the job. so .13mm-.15mm
45/30-06OKIE
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Ok can you give the measurements for the Suspect BCG gas rings and then that BCGs bore? Sorry if this sounds rude but I'm just try to simply my question as best as I can, sorry.
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lernerk392
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That doesn't sound rude at all. I'm getting 12.62mm-12.65mm. Hard to get good photos, but here’s a couple:
45/30-06OKIE
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0.9mm is what I'm getting as the difference between the two parts. .497in and .534in when converted to standard. Which is .037in difference! That's significant.
Here is a .035 feeler gauge for reference.
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lernerk392
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That's wild! Thanks for the feeler gauge photo, that is significant. Especially for system that needs to be gas tight. Wish i had all the fancy gauges that School of the American Rifle does lol Either way, I'll be sending in a ticket to PSA in a few moments with the findings. Starting to wonder if I even need to be shooting with this BCG at all tomorrow...
45/30-06OKIE
Member
Don't get me wrong, it will still be safe to shoot, just not fun, lol. But yeah you don't need those fancy gauges lol. You can get some mechanic/machinist Inside Bore Gauges and Outside Micrometers and do the same exact thing. And plus you know EXACTLY what size something is. Idk if they make ones small enough for the really tiny bores in ARs but I think you can get some for the BCG bore at least. And the barrel extension of course.
tactikel
Member
Clean both guns, twice, right down to the firing pins. Change mags. Try different ammo brands. Make sure the AR is running “wet”, the hellcat must have a light weight lube. Have a friend shoot both and see if the same problems happen.
Good luck.
Good luck.
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