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  #1  
Old 10-08-2018, 10:07 PM
krdomingue krdomingue is offline
 
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Default Dupage/Bula build short stroking

Put together my DuPage parts kit with a Bula barreled receiver and head spaced bolt. It is short stroking every shot. In some cases it doesn't eject the spent cartridge, but mostly it ejected the cartridge without picking up the next round. I believe I put it together correctly, but I have little experience with the M14.

What I have done:

-Made sure the gas cylinder is tight.
-Greased the rifle similar to how I would do a M1 Garand.
-Use two different magazines, one a USGI Checkmate, and the other an unmarked aftermarket brand.

Any suggestion on what else to look at?

Thanks,
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  #2  
Old 10-08-2018, 10:31 PM
Shomway Shomway is online now
 
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Have you confirmed the gas ports on the barrel and gas cylinder are properly aligned?
To verify watch this at about the 5:40 mark.....
https://www.youtube.com/watch?v=uCyYx0GpixM

Since these are used kits you might want to check the length of the recoil spring. I believe they should be around 15"-15 1/4" long.
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Last edited by Shomway; 10-08-2018 at 11:02 PM.
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  #3  
Old 10-08-2018, 10:37 PM
TLB TLB is offline
 
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Spindle valve between open and closed position?
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  #4  
Old 10-08-2018, 10:38 PM
4gun-drill 4gun-drill is offline
 
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I don’t intend to sound like a smart-A, but did you give the barrel and chamber a thorough cleaning? A co-worker of mine just did a similar build and based on other reviews of Bula chambers I looked closely at his. It took a LOT of scrubbing to get out all of the dried oil / preservative; there is no way it would have functioned like that. Likely it would have short stroked, if it chambered at all.
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  #5  
Old 10-08-2018, 10:54 PM
Password is Taco Password is Taco is offline
 
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Does it pass the tilt test? Lock the bolt back and tilt to see if you can hear the gas piston sliding back and forth. Then try the other tilt test, remove the op rod spring and tilt to see if the bolt slides freely.

The gas cylinder and piston on mine from Dupage was gummy, needed a good cleaning to pass the tilt test.
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  #6  
Old 10-09-2018, 01:56 AM
gregj gregj is offline
 
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The spindle valve on my parts kit was a gummy mess. Had to soak it with clp for a while. It works perfect now.

HTH
Gregj
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  #7  
Old 10-09-2018, 04:56 AM
nf1e nf1e is offline
 
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What ammo?

A thorough cleaning including a chamber scrubbing with solvent is necessary on pretty much any new rifle that has heavy preservative oil put on at mfg.
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Last edited by nf1e; 10-09-2018 at 07:19 AM.
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  #8  
Old 10-09-2018, 05:24 PM
krdomingue krdomingue is offline
 
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Quote:
Originally Posted by nf1e View Post
What ammo?

A thorough cleaning including a chamber scrubbing with solvent is necessary on pretty much any new rifle that has heavy preservative oil put on at mfg.
Turkish 308 produced in 2015. Non-corrosive
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  #9  
Old 10-10-2018, 04:37 AM
nf1e nf1e is offline
 
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Quote:
Originally Posted by krdomingue View Post
Turkish 308 produced in 2015. Non-corrosive
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.

This photo of an oversized neck rammed into a Sheridan SAMMI .308 shows a pretty good example of what I am trying to describe. Pay attention to the bump in the neck.

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Last edited by nf1e; 10-10-2018 at 04:50 AM.
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  #10  
Old 10-11-2018, 06:02 AM
mac1911 mac1911 is offline
 
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Quote:
Originally Posted by nf1e View Post
What ammo?

A thorough cleaning including a chamber scrubbing with solvent is necessary on pretty much any new rifle that has heavy preservative oil put on at mfg.
My dads words echo here.... "A new gun is far from clean"
Also the stuff they are coating metal with these days is generally a water based rust prohibitors far from lube.
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