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  #11  
Old 10-11-2018, 11:48 AM
M14 M14 is offline
 
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Location: south mississippi
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Other than what has been posted Mac, you need to have the headspace checked. I ran into several with headspace that was .002 under SAAMI min. specs. With that foreign ammo, that is where I would start, after cleaning the chamber well.

The others were rough chambers from factory reaming that leave lines that grab and hold the cartridge case just long enough to allow it to bleed enough gas off through leaky spots, and cause it to short stroke or not stroke at all. You can usually see these lines and scratches, but not always. Close inspection of the chamber with a good light source is advised.

Leaky spots means between the D tail of the piston and gas cylinder clearance cuts, the vent hole in the cylinder, or a worn out gas cylinder that is out of specs with the piston outside diameter clearance, etc. It only takes a few milliseconds of loss of gas pressure to cause a failure.

Let us know what you find or if you need any more assistance, and good luck.
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  #12  
Old 10-11-2018, 05:28 PM
Deuceguy Deuceguy is offline
 
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i don't think this a chamber and headspace problem. It's a gamble with worn parts.

Last edited by Deuceguy; 10-11-2018 at 05:34 PM. Reason: Spelling
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  #13  
Old 10-17-2018, 07:34 AM
M14 M14 is offline
 
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Quote:
Originally Posted by Deuceguy View Post
i don't think this a chamber and headspace problem. It's a gamble with worn parts.
Just going by my previous firsthand experience and finding 18 now with bad chambers, and 6 with short headspace. Every one of them was short stroking or not stroking at all.

Conversely, I have only seen one surplus rifle kit out of several hundred, that caused any malfunctions at all. It was a worn out gas cylinder, so I play the odds when I post trying to help someone and try to cover all the bases.

Let's just hope he gets it sorted out and updates us. Any side bets?
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  #14  
Old 10-17-2018, 10:10 AM
nf1e nf1e is online now
 
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I am going to go with what Deuceguy has to say.
He would be much more knowledgeable on this particular subject than anyone anywhere.
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  #15  
Old 10-17-2018, 06:47 PM
Deuceguy Deuceguy is offline
 
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Thanks Art!

M14- are you saying that my PTG gauges are broke?
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  #16  
Old 10-17-2018, 10:04 PM
Gewehr43 Gewehr43 is offline
 
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Can you two refrain from stomping on the OPís post and turning this into another embarrassing example of childish purse swinging from this forum?

Just once...... please?

OP:
I would check and clean the gas system up front, do a ďtilt testĒ, then clean the chamber real well and using some good US ammo, see where you are......
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  #17  
Old 10-18-2018, 04:59 AM
nf1e nf1e is online now
 
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Quote:
Originally Posted by Gewehr43 View Post
Can you two refrain from stomping on the OPís post and turning this into another embarrassing example of childish purse swinging from this forum?

Just once...... please?
Please let me explain Sir. Not stomping on the OP's post at all.
Deuceguy would be the only person here to have first hand knowledge of the barreled action the OP had a question about other that the OP.
Chances are , he is the man that barreled the action to start with.
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  #18  
Old 10-21-2018, 07:39 PM
Deuceguy Deuceguy is offline
 
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Didn't think I was purse swinging. nf1e is not stomping and he is correct. I just want to see this gentleman's rifle run and that he is happy. That's really all I care about.
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  #19  
Old 01-30-2021, 07:06 PM
krdomingue krdomingue is offline
 
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Quote:
Originally Posted by nf1e View Post
Sound like the Wally World $9. per box ZQI stuff.
I was using that for function testing rifles for a time but found it very inconsistent and occasionally, like 1 in 5 had bulge in the neck caused by an overly aggressive crimp and thick brass walls that would jamb.
Did not like to chamber completely in a SAMMI .308 chamber but works fine in a NATO chamber. Had similar problems with Malaysian L2A2.

Suggestion, try some US produced ammo and I think you problem will go away. Seen it many times.
Finally got around to working with this again and it was the ammo.

I made sure the gas cylinder was properly aligned, that the spindle value was in the correct position, that the gas piston moved freely and passed the tilt test. Cleaned and lubed it well and it was still short stroking. Changed out the ammo for Creedmoor Winchester .308 and worked fine. Which is great, but I don't have a lot of the Creedmoor ammo. I have some Aussie surplus that I will try next time.

Thanks for the help and sorry for being slow at get back to this, but life and procrastination got in the way. I have one more kit to build, but that will wait a little longer.
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  #20  
Old 01-31-2021, 12:25 PM
nf1e nf1e is online now
 
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Quote:
Originally Posted by krdomingue View Post
Finally got around to working with this again and it was the ammo.

I made sure the gas cylinder was properly aligned, that the spindle value was in the correct position, that the gas piston moved freely and passed the tilt test. Cleaned and lubed it well and it was still short stroking. Changed out the ammo for Creedmoor Winchester .308 and worked fine. Which is great, but I don't have a lot of the Creedmoor ammo. I have some Aussie surplus that I will try next time.

Thanks for the help and sorry for being slow at get back to this, but life and procrastination got in the way. I have one more kit to build, but that will wait a little longer.
Awesome. Glad to have been of some service Sir.
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