AMT .380 Backup - Light Hits on Primer

Discussion in 'Gunsmithing Forum' started by danf_fl, Apr 28, 2014.

  1. danf_fl

    danf_fl Retired Supporter

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    I got one in today with the problem of light primer hits.
    The gun was inherited from father and has not been fired for about 10 years prior to taking a concealed carry course with it.

    The customer bought Aguila .380, 95 gr FMJ.

    I did the pencil test (pencil down the barrel, pull the trigger and see how high the pencil goes), and the pencil jumped about 3/4". My KelTel P-3AT kicks the pencil out of the barrel.

    I suspect main spring is weak.

    Thoughts?
     
  2. Bluestar99

    Bluestar99 New Member

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    I inherited the same gun from my FIL. It had not been fired in 20 years. I cleaned it best I could without breaking it down. Had I been able to figure out taking it all the way down I would have. I had trouble with it firing and it never cycled right. Took it into my gunsmith and he tore it down and cleaned it well. It shoots great now. No issues. He did say it was a bugger to get apart.
     

  3. Tackleberry1

    Tackleberry1 New Member

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    Talk about the Walking Dead of the gun world...

    Shot an AMT Back up in .45 ACP back in the 90's and wholly cow, what a POS...

    A few months later I ran across an old timer with an AMT .30 cal... Complete opposite, a dream to shoot and easily the most accurate auto I'd ever handled.

    Just could not believe the quality swing from one model to the other from the same builder.
     
  4. robocop10mm

    robocop10mm Lifetime Supporting Member Lifetime Supporter

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    I'm leaning toward dirty firing pin channel. Gummy, carbon, lint. All together can cause havok. A good cleaning is the first step
     
  5. Bluestar99

    Bluestar99 New Member

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    I did a little research when I got mine and it seems that they were either great or garbage, no in between.
     
  6. danf_fl

    danf_fl Retired Supporter

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    I found a nick on the firing pin where the take down pin goes through the slide. I smoothed it out, and cleaned the firing pin channel.

    The pencil test still has the pencil coming out about 3/4". I am going to do some test firing later with different ammo than the customer shot.
     
  7. jason79

    jason79 New Member

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    A lot of videos on YouTube about disassembly, test firing and everything in between. Check them out, it might help.


    Sent from my iPhone using Firearms Talk
     
  8. danf_fl

    danf_fl Retired Supporter

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    Thanks! I checked them out. The firing pin looks to be okay. The channel for the firing pin is clear. There was a nick in the firing pin, but I got it smoothed out and have the firing pin moving free.

    I have some of the original ammo the customer used and 2 other brands I plan to use when test firing.

    I just have to get to the range now.
     
  9. danf_fl

    danf_fl Retired Supporter

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    Update - I went to the range.
    The pistol worked with Blazer and Federal .380 ACP.
    I tried some of the customer's supplied ammo, and problem returned.

    Bottom line: nick on firing pin and ammo.
     
  10. John_Deer

    John_Deer New Member

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    The ammo must not be any good. The pistol fire with two different brands of ammo. The owner has been hauling that ammo in the car or something improper.
     
  11. danf_fl

    danf_fl Retired Supporter

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    I took the P-3AT and PPK/s out at the same time and the customer supplied ammo work in both of those. I suspect hard primers.
     
  12. molonlabexx

    molonlabexx New Member

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    Definitely seems like a weak spring. That or there is a lot of GPR buildup in the channel. Give it a good cleaning and then start eliminating weak spring problems!