Old 1939 PPK with new springs.

Discussion in 'Technical Questions & Information' started by caveman60, Jun 7, 2012.

  1. caveman60

    caveman60 New Member

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    Finally, the old PPK is working "almost" like new...except for one problem...The slide will not lock open on the last round fired. I have purchased springs from both Numrich and Wolff and tried 3 different types of ammo. If I pull the slide back, with the empty "clip"-"mag" (you know what I mean !!!) inserted, it locks every time. Any suggestions would be very "helpful"... nomenclator or nomenclature excluded. Have a great day, T
  2. Hammerslagger

    Hammerslagger New Member

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    Have you changed the magazine spring?

    From what you describe, you seem to have a "timing problem". If I understand correctly, when you draw the slide all the way rearward, with an empty magazine in place, the slide locks open. However, it does not lock open after firing the last shot from the magazine.

    This sounds like that either the slide is not going fully rearward upon firing, or that it is cycling so fast that the magazine spring is failing to drive the slide catch up fast enough to catch the slide after the last shot form the magazine.

    Since you have changed the recoil spring twice, and tried several different brands of ammo; I find it unlikely that you problem is just springs and/or ammo. If you do have a new magazine spring installed, and the gun is properly lubricated; I would suspect that the gun might short stroking because the shooter is not holding the pistol with a firm grip, locked wrist, and stiff arm to give it sufficient resistance to recoil against to cycle properly. However, if the foregoing is the problem, the gun would likely be jamming (failure to eject and feed) quite often.

    One final thought based on observations over many years; sometimes semi-auto pistols will not cycle properly because they have become damaged and are mechanically out of proper alignment. Thus they bind when they cycle, and do not work as designed.

    Hope some of the above may be useful.
    Last edited: Jun 7, 2012
  3. Jim K

    Jim K New Member

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    Also it might be a good idea to check the slide stop spring. Sometimes someone will replace that spring with a stronger one that will resist pressure from the magazine follower enough to prevent the slide stop from coming up.

    Jim
  4. caveman60

    caveman60 New Member

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    First reply to Mr. Hammerslagger... No, I did not replace the mag. spring, but I am using the orig. one, plus a new one I purchased, last time I ordered ammo. I also thought of that idea: If I were "not holding the pistol with a firm grip, locked wrist, and stiff arm to give it sufficient resistance to recoil against, to cycle properly". I held that pistol VERY tight, with both hands and locked elbows... and one time, out of 50 rounds, it did in fact, lock back !!! I believe the new recoil springs (both???) for this old gun, are too strong??? I'm thinking about cutting 1/2 coil off of one spring and giving it a try??? (your opinion?) (I'm very careful, when cleaning and lubing - Clean it well, but don't OVER-lube it.)

    To Mr. Jim K... I checked that out, the best I could. By pulling the slide back slowly, I watched the mag. stop, pop right up, every time. The slide stop spring did it's job, without fail. That mag. spring is very strong. It takes an effort, to push that last round into the mag. Thank you men, for the advise.
    (I will NOT do any cutting, until I check back here !!!!) Going to the range this morning and will TRY to hold the PPK, with an "IRON FIST" !!!!
    Have a great day... T
    Last edited: Jun 8, 2012
  5. caveman60

    caveman60 New Member

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    To Mr. Jim K... I meant to say... I watched the "slide stop", pop up every time. The slide stop spring (IMO) was doing its job.
  6. Hammerslagger

    Hammerslagger New Member

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    For caveman60;

    Sometimes shortening a recoil spring will help with cycling problems; but doing so is usually not the preferred way of trying to cure them, and sometimes causes other problems like failing to properly return and hold the slide or bolt completely back into battery for the next shot.

    Please note that I am referring to making a recoil spring weaker by shortening the spring as compared to installing a lighter (weaker) recoil spring of the correct length. As a common example, the Ruger "Mark" series pistols are set up by the factory to function with commonly available .22 LR HV ammo, and still function reliably with most USA made Standard Velocity ammo. However, they often have problems cycling with soft recoiling ammo like "Wolf Match Target' that is actually made by Lapua in Shul, Germany. Ruger does not offer a weaker (match target) recoil spring assembly, and cutting coils off of a "Mark" recoil spring assembly just ruins the spring, and causes the bolt to fail to reliably return to and stay in battery. If one wants a Ruger "Mark" to run with very light recoiling, match grade ammo; the mainspring and/or the bolt has to be lightened, leaving the recoil spring alone.

    Your problem is somewhat unusual, in that the gun seems to cycle properly, except for locking open on the last shot. The main spring enters into the cycling equation of a PP/PPK type pistol. It has to be
    compressed by the cycling of the slide and offers resistance to the slides recoil.

    Did you change the mainspring, also? If so, I would begin by putting the original springs back in the gun and testing it. If this cures the problem, I would install one new spring at a time and test, until you find the spring that is causing the problem.

    Another odd thing that comes to mind relative to PP/PPK type pistol reliability is chamber cleanliness.The chamber my look clean but not actually be so from normal manual cleaning. Get some really aggressive bore cleaner like "Shooter's Choice", a bronze bristle brush (not nylon that looks like bronze) that is a really snug fit in the chamber, a length of cleaning rod that can be chucked in a variable speed electric hand drill. Run the drill at an estimated 50 to 200 rpm and thoroughly scrub out the chamber with the brush and solvent until absolutely clean.

    Hope something above helps.
  7. caveman60

    caveman60 New Member

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    Hello again MR. Hammerslagger... Thank you VERY much, for all the info. given in your thread... I have plenty of cleaning equip. to hack up. I will cut one and use the drill as you suggested. As I mentioned in a previous thread; The original spring looked like it came from an "old truck part"... Not even close to the shape required for this pistol. I will completely clean and take it to the range again. Dad left me this gun and I'm beginning to think this pistol has been through "Alot", since 1939 !!! I'm very thankful that it works at all. Thanks again and have a great day... T
  8. caveman60

    caveman60 New Member

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    MR. Hammerslagger... Did as you suggested... Used the drill and a bronze bristle brush on the chamber... WOW!!! ... Worked on it for more than an hour, just spraying and drilling, before the patches finally came out clean. Back to the range, to try it again. Thank you, T
  9. Hammerslagger

    Hammerslagger New Member

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    Let us know if your problem is cured.
  10. caveman60

    caveman60 New Member

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    Mr. Hammerslagger; The older we get, the faster time goes by !!!! (My father's favorite saying.) Well, I'm only 67 and that saying is finally hitting me, big time. I've been working on a new purchase, (NIB sig 230 - made in 1987) so have been going to the range, burning up a ton of .380 ammo, getting used to it and at the same time, wearing it in. I finally brought the PPK with me a few days ago and found that the slide, still will not stay open after the last shot. I finally decided to purchase a large magnifying glass and think I've found the problem???
    Looking VERY CLOSE, at the spot where the slide stop is supposed to catch the slide, I could
    see some wear. (Very little wear, but almost like a small ramp is warn into the slide?) IMO, it could be enough to cause my problem? I have not done THIS yet; but I am thinking about filing, with a very small file, a "flat spot" into the slide, just where it's warn??? ANY thoughts you may have on this "solution"???
    ByTheWay - I am not worried in the least, if this affects the value of my gun. It will be with me, for as long as I'm here... and... I would like it to work as designed !!!!! Have a great day... T
  11. Jim K

    Jim K New Member

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    That slide stop engages a fair amount of the slide, so I somehow doubt any wear that has to be found with a magnifying glass is the problem.

    One of three things is happening - the slide is not coming back far enough to lock, which is probably due to a too strong spring or too weak ammo, OR the slide stop is not working right, OR the magazine spring is weak or the follower not working right.

    Jim
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