PM45 RSA Experiment

Discussion in 'Kahr Club' started by Delleetodd, Sep 10, 2018.

  1. Delleetodd

    Delleetodd

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    PM45 force at rest 9.1 pounds.
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    Force at 1.6” compression 18.5 pounds. This is about the length of the guide rod protruding from the slide when racked all the way back.
    D3C5527B-5C33-4878-B058-A43B5CE84DE0.jpeg
     
  2. Delleetodd

    Delleetodd

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    Coil bind of large outer spring happens slightly past 1.25 inches. RSA gets stiffer at that point as the inner stiffer spring takes over until 1.6 inches max compression.
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  3. Delleetodd

    Delleetodd

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    Slide back 0.25” only the inner rod protruding. Guide rod now has tons of room to move around and nut can hang up on slide out of battery. Spring could potentially pop out the end. Not good.
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  4. Delleetodd

    Delleetodd

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    This is how it should look and this is how my CM9 works. Outer guide rod is proud of the hole first followed by the inner rod. Nut cannot hang up and spring cannot jump out.
    F89EB29C-619D-486E-B5AA-C9A64E784B69.jpeg

    I think the inner spring should be stiffer. I sometimes feel the slide bottom against the frame. I have 2 RSAs that are the same. I have a bunch of springs and even a P45 guide rod on the way to experiment with. If I can’t find the right combination for the dual spring RSA I will try to get a single spring RSA to work. I really like this gun but this bothers me and I feel the need to fix it.
     
  5. bac1023

    bac1023

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    Interesting

    Good luck with it...
     
  6. Delleetodd

    Delleetodd

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    Here is the CM9 RSA next to the PM45. The CM9 inner spring is more compressed and the outer spring has one less coil. CM9 RSA starts at 9.9 pounds and finished at 19.9 pounds. As the slide sits at rest the CM9 inner recoil spring hasn’t compressed at all which is what I’d like to see with the PM45.
    1FA446C4-8F61-43E1-9B0B-36FC83BA9092.jpeg
     
    Last edited: Sep 11, 2018