3rd Generation Glock 34 locking block pin coming out while firing

[chbrow10]

First of all, this gun is used by my two sons. They share the gun in matches. So when/if the gun craps out, two shooters get effected with stage DNFs. This is something that I will do anything to avoid. On top of that, we are going to the Mississippi Classic on 4 weeks time, where this gun will be shot by both boys.

The symptom is that the locking block pin is coming out of the left side of the frame while the gun is firing. I can push the pin back in with an ink pen, and it might run for weeks, or it might repeat itself on the next stage. Yesterday, it happened twice, so I took the pin out and turned it around (I think). The gun ran fine for two more stages (one stage shot one time by two kids).

This has been happening for about 3-4 months. At first I thought that the pin was being over lubricated, so I wiped it dry, but then it happened again yesterday.

Since I am short on time, I will be happy to buy a spare locking block, or a spare pin, or whatever.

Do these pins have a directionality, meaning that you can put them in backwards? I did a search for this in the Glock archives, but couldnt find it on the Enosphere..

Any help is tremendously appreciated.

Edited April 19, 2010 by chbrow10

[GlowingDonut]

That pin is held in by the slide stop. I'd replace the pin if the groove is worn or rounded, or the slide stop if the SS hole the pin goes through is worn. I believe the locking block pin is reversible, and has slide stop slots on both ends.

Do these pins have a directionality, meaning that you can put them in backwards? I did a search for this in the Glock archives, but couldn’t find it on the Enosphere..

Any help is tremendously appreciated.

[JTew]

Both the Locking block pin and the trigger pin can go in either direction and the pins are reversible. The recommended method is they get pushed out from the left to right and put back in from right to left (the left side being the magazine release side). A couple of mine are really loose, but they have never worked themselves out of the frame. I would replace the pin. If that does not work, then a small drop of blue locktite should hold it until you take it out again.

[twodownzero]

The locktite designed for cylinder sleeves might be a better choice for this application, if it won't cooperate.

[chbrow10]

Maybe I had the wrong pin in the original post. This is the pin that the slide stop spring pin rests on, the upper small diameter pin. It is NOT held by the slide stop, it is the pin above that.

Edited April 19, 2010 by chbrow10

[GlowingDonut]

The top smaller pin is the slide stop pivot/locking block pin. The lower (larger) pin is the trigger pin. The wire spring on the upper SS pin keeps the lower trigger pin in place.

[Nik Habicht]

Maybe I had the wrong pin in the original post. This is the pin that the slide stop spring pin rests on, the upper small diameter pin. It is NOT held by the slide stop, it is the pin above that.

Replace the pin, they're cheap. If the problem continues, you can try and replace the locking block (little bit more money, but not awful), or teach your sons to just push the pin back in place with their finger tip at the end of the stage or at a safe table....

Is the locking block cracked? Frame cracked? Those would be my only other questions....

[Nik Habicht]

The top smaller pin is the slide stop pivot/locking block pin. The lower (larger) pin is the trigger pin. The wire spring on the upper SS pin keeps the lower trigger pin in place.

The top, smaller pin is not the slide stop pivot however -- the slide stop pivots on the trigger pin....

[Glockcomma]

I had this happen to me at a match, the RO pointed it out to me. I had a spare in my bag installed it in the safety area and never had another problem. It always amazed me that the pin would wear and not the polymer.

Tim

[JBP55]

I replaced the pin in an older Glock that had the same problem and it would also work its way out as the hole in the frame was slightly over sized. It was shipped to Glock with an explanation. I have not seen the gun since it returned from Glock but the owner said it works fine now.

[chbrow10]

JBP55, you are saying that this happened and you replaced the pin and it still happended?

Glockcomma, you are saying that this happened and you replaced the pin and it did NOT happen again?

Thanks for the responses guys, I've got some new parts on the way, spares I should probably have anyway.

[bisdak]

This happened to me in the match also. I think the pin got worn out and becomes a little loose. I replaced the pin and never happened again. To OP, do you frequently detail strip your Glock or remove the pins, then I think this makes it wear out faster and loosens up a bit. Just replace the pin.

Edited April 20, 2010 by bisdak

[BoyGlock]

I had the same problem in one of my glock35 years ago. I planned to fabricate an oversized pin from a drill bit, but the gun was sold before I had the chance to try it. You can try it if the oem spares wont solve the problem.

Edited April 20, 2010 by BoyGlock

[chbrow10]

I detail strip the gun about 6 times a year, so I do remove that pin more than most.. Got a new pin coming... And a new locking block... and a new slide stop spring... just in case.

[BoyGlock]

I detail strip the gun about 6 times a year, so I do remove that pin more than most.. Got a new pin coming... And a new locking block... and a new slide stop spring... just in case.

I think your frequency of detail stripping is well w/in tolerable limits if you shoot a lot. A well made equipment like the glock should not be bothered by this.

[open17]

I detail strip the gun about 6 times a year, so I do remove that pin more than most.. Got a new pin coming... And a new locking block... and a new slide stop spring... just in case.

Had one that wanted to drift out on one of my G35's. Replaced it and it has stayed in place since. Also broke one in half on an Open G17.

WHERE did you find just the slide stop spring? You are talking about the little U shaped

wire spring? I wasn't aware it was available seperately.

Edited April 20, 2010 by open17

[njl]

I detail strip the gun about 6 times a year, so I do remove that pin more than most.. Got a new pin coming... And a new locking block... and a new slide stop spring... just in case.

That seems a little frequent to me...and depending on the tool being used to punch the pin out and the way it's being done, I wonder if that's enlarged the locking block pin holes in the frame?

Seems like a bandaid solution...but perhaps a little strip of grip tape covering the locking block pin hole would keep it in place?

Other possible solutions:

1) buy an older Gen3 G34...the originals didn't have locking block pins.

2) send it back to Glock...worst case, they might replace the frame for free...and then you have a mismatched serial Glock. Some people don't care about that sort of thing...some do.

[chbrow10]

Open17, I'm ordering a completely new slide stop, with the spring on it

njl, Sending it back to Glock is not an option as I have a major match in 3.5 weeks, and I won't get the gun back by then.

Boy Glock, Every month this gun shoots at least 600 rounds, more if we practice. So this gun gets shot a bunch.

[BBJones]

I detail strip the gun about 6 times a year, so I do remove that pin more than most.. Got a new pin coming... And a new locking block... and a new slide stop spring... just in case.

Other possible solutions:

1) buy an older Gen3 G34...the originals didn't have locking block pins.

2) send it back to Glock...worst case, they might replace the frame for free...and then you have a mismatched serial Glock. Some people don't care about that sort of thing...some do.

There were no "older" Gen3 G34's that were 2-pin models. I have have Gen3 G17 2-pin, but Glock moved onto 3pin before the G34/35 models were released.

(My first post. No longer a lurker)

[Nik Habicht]

Seems like a bandaid solution...but perhaps a little strip of grip tape covering the locking block pin hole would keep it in place?

Not if they're shooting production, please.....

[Nik Habicht]

There were no "older" Gen3 G34's that were 2-pin models. I have have Gen3 G17 2-pin, but Glock moved onto 3pin before the G34/35 models were released.

(My first post. No longer a lurker)

I guess I must be imagining things then --- because I've owned three G-34s that were only on two-pin Gen. 3 lowers. The one I shot three USPSA Nationals with is still in the safe....

The redesigned locking block arrived late to the 9mm Gen 3 guns, sometime in the early '00s. My blasters were bought new in 2000-2001 originally, and I was late to the party, as the G-34/5 were released in what? 1995 or so....

[sfchorn]

One other possibility to consider is the order in which the pins are installed. The slide stop spring is designed to keep pressure on the locking block pin. If you install the pins in the wrong order, there will not be any tension. This can cause the pin to walk out during recoil.

Just don't ask me how I know........

[njl]

There were no "older" Gen3 G34's that were 2-pin models. I have have Gen3 G17 2-pin, but Glock moved onto 3pin before the G34/35 models were released.

(My first post. No longer a lurker)

That is incorrect. It was at least 2001 (perhaps 2002) before Glock switched the mid/full-size 9mm's to 3pin frames. I know this because it happened in the middle of the GSSF 10th anniversary G17 run. The first 500 (not sure if that's GSSF000-GSSF499 or GSSF001-GSSF500) are 2pin frames. The second 500 were 3pin frames.

According to wikipedia, the G34 came out in 1998. My G34 is a 2pin frame.

If you said all G34s are at least 3rd gen, I'd believe that without trying to look it up.

[njl]

One other possibility to consider is the order in which the pins are installed. The slide stop spring is designed to keep pressure on the locking block pin. If you install the pins in the wrong order, there will not be any tension. This can cause the pin to walk out during recoil.

Just don't ask me how I know........

That'll also likely cause problems with function of the slide stop...not enough spring tension pushing it down.

[njl]

Seems like a bandaid solution...but perhaps a little strip of grip tape covering the locking block pin hole would keep it in place?

Not if they're shooting production, please.....

I don't shoot USPSA, so I didn't realize production forbade grip tape up in that portion of the frame.