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  #11  
Old 10-17-2020, 01:28 PM
03man 03man is offline
 
Join Date: Feb 2015
Location: near Charlotte NC
Posts: 138
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Did you strip/clean/lube and trouble shoot as suggested before this last outing?

I have 20 or 22 carbines and have fired each in the last several months, none of them exhibit the "problem" you describe. It is something in your trigger housing and/or hammer/sear engagement.

15 round mags are not creating the problem. JMHO.
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  #12  
Old 10-17-2020, 01:40 PM
6 Ring 6 Ring is offline
 
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Location: South of Atlanta, Ga
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I would try another sear.
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  #13  
Old 10-17-2020, 01:56 PM
Panzerschwein Panzerschwein is offline
 
Join Date: Jul 2020
Location: North Las Vegas, Nevada
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Thanks, gang. The inside of the group is spotless and properly lubed. I used solvent, Q-tips, and pipe cleaners in every square nook.

I think I’ll try and get ahold of a spare trigger group from somewhere just to see. It’s driving me mad!!

Last edited by Panzerschwein; 10-17-2020 at 02:04 PM.
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  #14  
Old 10-17-2020, 03:39 PM
03man 03man is offline
 
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Didn't you have this same problem before the new parts?

Been a while , so maybe I remember wrong.
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  #15  
Old 10-17-2020, 03:41 PM
Panzerschwein Panzerschwein is offline
 
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Quote:
Originally Posted by 03man View Post
Didn't you have this same problem before the new parts?

Been a while , so maybe I remember wrong.
It was doubling and having lots of hammer follows. Now itís only on the
last round of the magazines.
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  #16  
Old 10-17-2020, 03:53 PM
03man 03man is offline
 
Join Date: Feb 2015
Location: near Charlotte NC
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Sounds like you have the same problem, just less often.

The only part you have not changed is the trigger and its spring, correct?

I'd take the complete housing out, and work it by hand until you duplicate the problem-
you may have to cycle the hammer by hand 100 times- but sooner or later the problem will show up and you can see which piece is not moving correctly.

There was a small change in trigger geometry also - early on- your problem may be related to the small "shelf" on the trigger. The front edge must be smooth to allow the sear to move up to reset.

Is the back edge of your sear straight, or slightly rounded?

Have you tried puting the original parts- hammer, sear- back in one at a time to see if the problem changes?

Even if a different THsg works fine, you still won't know what is wrong with yours.

Spend the time to function it by hand till you wear your fingers out!
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  #17  
Old 10-19-2020, 01:38 PM
35 Whelen 35 Whelen is offline
 
Join Date: Dec 2011
Location: Texas
Posts: 93
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I know you've replaced the sear and hammer, but this sounds to me like a sear engagement issue.

It would stand to reason that after the last round is fired, the forward velocity and inertia of the bolt is much higher because its movement is not hindered by chambering a new cartridge and dragging across the top of a cartridge in the magazine. The bolt could then close, possibly slamming with enough force that the hammer would be jarred and fall. This hypothesis is somewhat supported by the fact that the rifle has been doubling and the hammer occasionally following the bolt down.

If this is what's happening, it would be very easy to diagnose with a magazine that holds the bolt open. Load one cartridge into said magazine, fire the single cartridge, remove the magazine while slowly lowering the bolt. If the hammer is cocked and you are able to dry fire, then you've definitely narrowed it down.
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  #18  
Old 10-19-2020, 05:56 PM
Ted Brown Ted Brown is offline
 
Join Date: Nov 2012
Location: Jacksonville, OR
Posts: 592
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Have you checked the gas system?
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  #19  
Old 10-19-2020, 06:25 PM
AWOhio AWOhio is offline
 
Join Date: May 2010
Location: Columbus OH
Posts: 376
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Load a mag, chamber a round, remove the mag, fire the round in chamber.

Does it do the same thing With no magazine as it does with an empty magazine?
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  #20  
Old 10-21-2020, 07:01 PM
Panzerschwein Panzerschwein is offline
 
Join Date: Jul 2020
Location: North Las Vegas, Nevada
Posts: 189
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Quote:
Originally Posted by 35 Whelen View Post
I know you've replaced the sear and hammer, but this sounds to me like a sear engagement issue.

It would stand to reason that after the last round is fired, the forward velocity and inertia of the bolt is much higher because its movement is not hindered by chambering a new cartridge and dragging across the top of a cartridge in the magazine. The bolt could then close, possibly slamming with enough force that the hammer would be jarred and fall. This hypothesis is somewhat supported by the fact that the rifle has been doubling and the hammer occasionally following the bolt down.

If this is what's happening, it would be very easy to diagnose with a magazine that holds the bolt open. Load one cartridge into said magazine, fire the single cartridge, remove the magazine while slowly lowering the bolt. If the hammer is cocked and you are able to dry fire, then you've definitely narrowed it down.
I think youíre definetly on to something. I got some snap caps and cycled the gun rapidly while holding down the trigger. Very consistently, I could replicate the issue. When I pulled the slide back and rode it home, the hammer stays back every time. But when the bolt goes home with no cartridge to ďcushionĒ it the hammer falls very often when the bolt slams home unimpeded.

Iíve got another trigger group coming in the meantime while I try and troubleshoot this one. Iíll let you all know what I find. Itís very strange though since I replaced the hammer, sear, and sear spring already. Maybe Iíll change EVERYTHING including every spring and pin in the trigger mechanism and the trigger itself.
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