GSG 1911-22 slide stop notch peening

Discussion in '1911 Gunsmithing' started by knedrgr, Dec 19, 2011.

  1. knedrgr

    knedrgr Low capacity, low tech...

    Aug 15, 2011
    I'm a new owner of a GSG 1911-22. After reading the complete ATI thread from Chris and mostly owners reporting problems, I went ahead and tried to get in front of those potential issues that may happen to MY gun. I know there are some owners that are running their guns without issues. Good for them.

    The slide stop notch peening issue is an problem that no one has seem to have a solution for. And I've read some wild guesses as to why the notch is getting peen at the very corner. To this, I will offer my theory.

    The notch is NOT being peen by the slide locking on the last round. It's being peen due to normal firing and every time the slide goes rearward and the stop is BOUNCING and kissing the notch. The reason the slide is not looking back is from the lack of an empty mag and follower to keep it in place.

    So the culprits behind this could be a couple of reasons:
    1) a weak plunger spring.
    I've taken mine apart and the stock spring is as strong as a wet noodle. It was a joke. So I replaced the whole plunger spring and ends with Ed Brown replacement kit. I also polished both ball ends with some fine grit sand paper for a smoother finish.

    After installing the new spring and caps, the slide stop wouldn't engage on an empty mag, which means that the new plunger spring was just a little too strong for the mag spring. I had to manually engage the stop upward. I removed the slide stop and saw the marking from the ball end. I took some used 600 grit paper, wrapped it around a small screw driver, and polished that area on the slide stop. Insert the stop and it worked on an empty mag.

    So, the stronger plunger spring will keep the stop from bouncing, during firing, and will properly lock the slide on an empty mag.

    2) hand grip.
    Depending on your grip, it can come into slight contact with the SS and cause it to move slightly up, thus making contact with the notch, as the slide goes rearward.


    So there are my theories, and I'm banking on number one, and I hope my "solution" will work out. Only time will tell.
     
  2. 50GI-Jess

    50GI-Jess Member

    497
    Aug 24, 2011
    Sometimes a lateral filed dentent groove on the SS, combined with either the standard detent spring, or a slightly stroner one, will also fix the problem. This old trick works like a little speed bump that keeps the SS in place while shooting.
     

  3. knedrgr

    knedrgr Low capacity, low tech...

    Aug 15, 2011
    Thanks Jess! That's also another great fix.

    My plan B was very similar to yours, but taking a different approach; re-profile the SS and give it a greater slope, thus forcing the SS to stay in place by the detent pin.
     
  4. Bender

    Bender Supporting Addict Supporting Addict

    Aug 15, 2011
    My Brown Kobra Carry peened badly,........TWICE.
    Brown fixed it by replacing the slide the second time, I then sold it.
     
  5. knedrgr

    knedrgr Low capacity, low tech...

    Aug 15, 2011
    Here's a picture to better help illustrate what I'm talking about.

    Here's the back side of the GSG slide stop. Note the scratch or contact area of the ball end of the plunger spring. You will also notice the two slopes; top and bottom, on this back side. The top slope should help to keep a downward force on the SS from bouncing up, during normal firing. And the bottom slope should help to keep the SS up, once the mag follower has engage the SS.

    You'll need to polish both of these planes for a smooth, low friction, travel for the SS to work with a true 1911 plunger spring that replaced the stock GSG plunger spring.

    [​IMG]
     
  6. knedrgr

    knedrgr Low capacity, low tech...

    Aug 15, 2011
    That effing blows Greg!
     
  7. knedrgr

    knedrgr Low capacity, low tech...

    Aug 15, 2011
    Went to the range yesterday, and put about 200 rounds thru her. The modified SS and new plunger spring works perfectly. And the slide doesn't show any signs of peening.
     
  8. Bender

    Bender Supporting Addict Supporting Addict

    Aug 15, 2011
    Awesome news!
     
  9. 50GI-Jess

    50GI-Jess Member

    497
    Aug 24, 2011
    Sometimes it's also the amount of SS engagement in the slide cut out that's insufficient. The SS needs as much contact with the slide as possible. If it only engage 1/2 or 2/3 into the cut out, the stress on the cut out area will show over time. Especially if the cut out area has sharp corners facing out, burrs of metal will migrate ourwards and seem sharp.
    The fix to this, is to slightly de-burr the sharp corners around the lines of the cut out area, and further more file the buttom groove inside the SS, to allow it further upward travel into the cut out notch of the slide. Thereby maximizing the 2 contact surfaces.
    Lastly, make sure the SS is not free hanging under recoil, by creating a positive detent effect on it, which can be done about 3 different ways. detent hole, groove or angle or a combination of the 3, depending on the amount of recoil/caliber and type of mags used.
     
  10. knedrgr

    knedrgr Low capacity, low tech...

    Aug 15, 2011
    Jess,
    Always appreciate great advices from 'smiths like yourself.
     
  11. 50GI-Jess

    50GI-Jess Member

    497
    Aug 24, 2011
    Thanks,
    Together we can fix pretty much any problem we may have on our 1911's.
    It's like being one big family of 1911 owners.
     

You need 3 posts to add links to your posts! This is used to prevent spam.

Verification:
Draft saved Draft deleted