Catastrophic Gen 4 Glock 17 Failure on Reassembly (Assembly Error Resolved)

[Naphtali]

After stripping and reassembling a Gen 4 Glock 17 (mfg date 4-30-14), I pulled the slide fully to the rear after inserting it back on the frame and got this:

photo 3.JPG

photo 4.JPG

Salient points here are:

1) The slide would always come to rest ~ 2mm forward of where it should normally sit.

2) The slide could be moved rearward fully, and when released it would return to the position in #1 above.

3) The slide could NOT be removed. The trigger could be dry fired each time the slide was pulled to the rear, but this (and/or depressing the normal release tabs on each side) would not allow the slide to come forward any further than in the photos. The pistol was dead in the water at this point.

4) The only place I can find where this exact situation has been reported previously is here: http://ingunowners.com/forums/handgu...-problems.html

5) There are a few YouTube videos showing that the RSA can be slightly off-center at its resting point on the barrel, and it will cause a very similar problem (e.g. https://www.youtube.com/watch?v=7gCcW4OrzQY ). HOWEVER, the slide is easily removed in these videos. In my case, and the link in point #4 above, the slide is stuck on the frame in a way that I thought I'd need an armorer to fix it after a few minutes of failing to fix this on my own.

6) After 5 mins of screwing around gently (just using my hands), I finally got the slide off when I pushed rearward on the front of the RSA with moderate force using only my finger, and it moved slightly rearward. At that point, the slide STILL would not come off. But the first time I dry fired after that, the slide shot forward off of the frame.

7) The rear portion of the RSA was obviously bent as soon as I did a full inspection. See picture just below. This was definitely NOT the case prior to reassembly - I had stripped the gun to find whether I had a certain part # RSA (042 I think) which is stamped on that rear portion. So I had coincidentally just scrutinized this very portion of the RSA prior to reassembly (as well as fine tooth comb examining the gun after purchasing it - I would not have missed this).

photo 1.JPG

So now I get to send this back to Glock for, at minimum, exchange of the RSA. It's probably shooting for the moon to expect that they would tell me how to prevent this from happening in the other Gen 4 G17 I recently bought (which is the adjacent serial # to this one). Or how to prevent this from happening again if I just get a new RSA. I have little doubt that I had the RSA slightly improperly seated against the barrel on reassembly, and that's why the reassembly went wrong. But...

1) This shouldn't turn the gun into a paperweight with the slide stuck on the frame, and a crazy fix of (A) push the RSA rearward with moderate force and (B) dry fire the gun to shoot the slide forward off the frame. Until you (somewhat counterintuitively) do exactly (A) followed by (B), the gun is a paperweight.

and

2) Using only my fingers to push the RSA rearward shouldn't have bent the RSA. When the slide was stuck on the frame, I never tried to push it hard forward. Mild-moderate force (maybe ~ 10 lbs) wouldn't do the job, so I didn't try to force it.

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Info on the weapon:
-- Glock 17 Gen 4, mfg date 4-30-14
-- Completely unmodified
-- 1,050 round count with no malfunctions other than ~ 1% BTF rate (using Speer GDHP 124 +P and Speer Lawman TMJ 124 primarily). Incidentally, the other identical model I have made on the same date also has a ~ 1% BTF rate. Both have an average ejection patters of 5:00 - 5:30, which sucks, which is why I recently (happily) converted to the HK VP9 full-time. My left-eye dominant wife got tired of getting hit in the shoulder / earmuff consistently by the brass from both G17s. I digress...
-- Maybe 10 total field strippings / reassemblies during this time, only had a problem with this last one

Info on me
-- Don't carry a gun in my career, but I've shot almost exclusively Glock 17s for the past 15 years, shoot expert IDPA, not a certified armorer or anything, but I've stripped and reassembled a variety of Gen 1 through Gen 4 G17s thousands of times.

So I don't really have a specific question other than if anyone has thoughts on the above. It's not a huge deal to me, as I've already solved my Glock problems by having switched to the HK VP9 for concealed carry and IDPA about a month ago. This experience just reaffirms the wisdom of that decision - I can't bring myself to keep giving business to a company that uses you (yes you, the person reading this post, and me too) in the real world / on duty to beta test their weapons. HK's and Glock's engineering departments are on opposite ends of the spectrum. I digress - and thanks in advance for any advice / input.

[Slvr Surfr]

I've never experienced an issue like you described. I do however own a Gen 4 G34 that I carry for duty. I never had btf issues, but did experience a lot of weak (barely dribble out brass) extraction issues. The gun would not extract the empty brass casings sans magazine.

If you plan to keep the guns, I would definitely look at the Apex Extractor kit with upgraded extractor and Extractor Depressor Plunger Spring. The weak ejection issue was fixed along with extracting without the magazine in place.

[samuse]

Looks like you somehow managed to get the barrel and recoil spring in front of the locking block and jammed the whole thing together forcing the recoil spring through the hole in the slide and clogging everything up.


There is no way that the barrel is in the locking block with the slide forward of the frame, with barrel and recoil spring sticking out of the slide.

[Cmm46]

I own 5 Glocks. I had the same thing happen to my gen4 17. Never had anything like it with the others. I figured I didnt have the recoil spring properly placed and it cause the rod and barrel to drop down and get hung up. I havent happened since but the gun is new with only about 500 rds through it.

[Stengun]

Howdy samuse,

Looks like you somehow managed to get the barrel and recoil spring in front of the locking block and jammed the whole thing together forcing the recoil spring through the hole in the slide and clogging everything up.


There is no way that the barrel is in the locking block with the slide forward of the frame, with barrel and recoil spring sticking out of the slide.

I was going to post the same thing but you beat me to it.

The OP reassembled it wrong.

Pretty simple.

Paul

[Naphtali]

I will accept that the RSA was probably malpositioned on the barrel (though I would have sworn I had it on there right, I wouldn't bet my life on it). But the barrel was definitely correctly positioned when I put the slide back on. How could it have slipped in front of the locking block? Did a slightly out of position RSA allow the barrel to slip forward / down as the slide was inserting?

[Naphtali]

Looks like you somehow managed to get the barrel and recoil spring in front of the locking block and jammed the whole thing together forcing the recoil spring through the hole in the slide and clogging everything up.


There is no way that the barrel is in the locking block with the slide forward of the frame, with barrel and recoil spring sticking out of the slide.

FWIW, when I reassembled the gun, pulled the slide to the rear and let it go forward, nothing seemed at all out of place until I looked at the gun and saw this after the slide came forward. The barrel and RSA appeared to be in the slide properly before I put it on the frame. Since I was holding the slide sights-up before I put it back on the frame, if I didn't have the RSA secure enough in place to hold itself and the barrel in the slide, the RSA and the barrel should have both fallen out on the ground.

There was no forcing of anything that led to this problem. If someone had turned the lights out as I was just letting the slide go forward on the frame, I would have thought it had reassembled correctly.

[MountainRaven]

I don't think I've ever seen any two people field strip and reassemble their Glock the exact same way.

That being said, perhaps a simple preventative step that I've added may help avoid this issue in the future - having seen this sort of thing happen not infrequently with Gen4 Glocks - ensure that the RSA is properly seated against the barrel and then put the slide back onto the frame, then stop once the slide/barrel assembly locks into the frame to verify proper reassembly and then run the slide to the rear to function check/load/whatever.

But, yeah, I've seen this happen a lot with Gen4s. That being said, I've never seen one where the RSA bent. I think it might be worthwhile to pick up a spare. Not as cheap as they are for the Gen3s, but still pretty cheap, and if this sort of thing happens again, at least you're not out a pistol waiting for a part or sending it back to Glock or to a Glock armorer.

[dentron]

My LE be buddy had this happen one when I was at the range with him. He fixed it, I think, by pushing the RSA rearword and pulling the slide rearward. I dont think he has had any problems since.

[kantstudien]

The Glock Armorer course addresses this issue. You did not install the RSA correctly, not the gun's fault.

Grab the very tip of the RSA and pull forward violently. It will reseat the RSA into the half moon of the barrel lug and fix your problem.