The Unofficial P64 Resource Forum

I recently purchased a fine example of the P-64. Thursday night I field stripped it for the first time, cleaned and inspected. Friday at the range, I started the functional check. On the last rd. of the first full magazine, the slide departed the frame and landed about 3 ft. in front of me. I reassembled and worked the action multiple times. Next I did 4 single rounds in the two magazines with all proper operation complete with slide hold open after the round. I ran a full mag through it and everything functioned properly. That night I again field stripped it. Saturday I took it back out and again on final round on a full mag. the slide exited the frame. So questions
Has anyone heard or experienced this before?
Is that something wrong that I am doing on reassembly?
Should I be looking for a crack or broken part?
Who is the best gunsmith for me to consult?
Any and ALL help and advice is appreciated

Welcome to the forum

Check to make sure the top of the front trigger guard didn't break off or is damaged.
Extend the trigger guard to inspect.

You shouldnt be able to take the slide off w/o extending the guard.

We have had at least one post on that failure.

If the trigger guard is broken there is a guy from Poland on gunbroker selling them.

Post pics of the TG if you can.

That is excellent advice. Of course it must have something to do with the trigger guard. It's the only part that ensures the slide doesn't come off. I will try to get some pictures. This P-64 was built in 1968 and after 55 years I'm thinking it has experienced wear on the guard. Thanks

As an after thought what maker and grain of ammo are you using?

I know I promised pictures and they will be forth coming. Ok so here is the latest. I just finished comparing the trigger guard with a model made in 1975. The one that malfunctioned actually has one in better shape. I have noted that the force required to pull it down seems weaker than the '75 model.
I left some info out that at the time did not seem relevant. The first time it was fired was when I let my friend at the range fire it. It did not happen when I retried it. The next day it also malfunctioned when I let another friend try it first. This weekend I will be the only one shooting it. Still I'd like a knowledgeable gunsmith inspect it first. Seen that you can order a replacement trigger guard spring, but I can't see where it fits.
To answer your question, I was trying out some PPU FMJ Brass cased 93gr. ammo.

My theory...the recoil is causing the muzzle to flip up hard into your trigger finger, which in turn is causing the trigger guard to drop for a brief instant. This would happen around the time the slide is coming back forward.

However, even that alone does not cause the slide to come off. The back of the slide still has to pivot up to clear the barrel, which to me implies it's slamming too far back, far enough for the guides on the slide to come out of the track (as if you were disassembling).

Recommendation: Get a new/stiffer recoil spring. This is a blow-back operated pistol. Both of the effects described above can be caused by ammo that is too powerful for the spring you have (either your ammo is hot, your spring is shot, or something else is going on).

I'd quit letting friends shoot my P64!

See my post on this issue with pictures. Here is the link:

viewtopic.php?f=3&t=4335

DRUM ROLL>>>>and the answer is.......weak trigger guard spring!!!
Since my first posting, I have acquired 2 models from J&G sales. Yesterday all 3 went to the range with me. The problem occurred with my 1968 model. The other 2 are 1974 and 1975 models. There is a substantial difference in the trigger spring tension with the '68. I ran 4 different mags with singles and then full through the '68 with no repeats. Hurryin Hoosier was right..part of the problem was others finger position. Thanks to espania 1958 for providing a link to this issue.
In my professional life, I am a flight test engineer and we have to many times look at all factors leading up to an incident. The coincident of a "snappy" recoil must have caused the others to reposition their hands and fingers on the gun and trigger to slightly drop the trigger guard causing a temporary unlocking of the slide. The blow back was enough to lift the slide off the rail enabling it to depart the frame.
I am waiting for "Robart" to send me replacement trigger guard spring, plunger and pin from Poland.
Now even with my bad experience with my first purchase I am thrilled with these guns and would not hesitate to recommend them to any shooter.

Good news, let us know how the fix works out.

My new friends,
I HAVE SO MUCH TO LEARN!!!!
The replacement parts arrived and I learned a new lesson. The early model guns have a different trigger guard, spring, plunger and pin. My '68 has a lighter spring, longer plunger and smaller pin. I continue to shoot it, noting my hand positions and have not had a reoccurrence of the problem. Does anyone know what year they modified the design of the trigger guard assembly?

Now the adventure continues. I field stripped the '75 and reassembled for the next trip to the range. It performed flawlessly but now I can't get the slide off again. What did I do wrong? How to I fix it? Again, all suggestions are welcomed.

You can use a pair of gloves to get a good grip and pushing forward with your grip hand and backward with your slide hand at the same time and see if that works.

When you get it off check the recoli spring to see if it is ground flat on the ends.

Yeah Curly I tried that. And even gave it to a younger man with a stronger grip to try. It is really stuck. So 2 of my 4 have problems. The latest one, a really beautiful perfect finish with wooden grips, resets the hammer ever time it fires. See my other posting. Guess I'm just gonna have to find a real gunsmith

Daddyursus wrote:Yeah Curly I tried that. And even gave it to a younger man with a stronger grip to try. It is really stuck. So 2 of my 4 have problems. The latest one, a really beautiful perfect finish with wooden grips, resets the hammer ever time it fires. See my other posting. Guess I'm just gonna have to find a real gunsmith

On the first gun, I'll ask the obvious - are you sure that you're getting the trigger guard completely down and off to the side? (I use the old trick of putting a coin between the trigger guard and frame, just to make sure that it stays down.)

On the second gun, I don't follow what you mean about "resetting the hammer".

I'll try your old trick for the first gun.

For the 2nd. After loading a magazine into the gun and racking the slide, my gun is set for SA. After firing, the shell is extracted and a new round chambered. But instead of the hammer staying back, it resets into the DA position. If I cock the hammer back and pull the trigger, the gun fires, slide back, eject casing, load new round and the hammer is back to the DA position. It is like it does a de-cock each time with no slam fire.