G20 Gen4: FTF Issues

[chucky2]

Went to a gun show this weekend with my bud, they had a Glock armorer there.  He took all my mags apart and looked at my G20 and noticed two things:

1.)  Mag springs on all of them were about an inch shorter than they should be.  He stretched them out from the middle outwards.  I don't store ammo in my mags, I don't even pre-load them before going to the range, and I hardly even load more than 10 rounds at a time.
2.)  Said not to run FrogLube in it, gets into everything (not sure I believe this, I read of lots and lots of guys running it in their Glocks, no problems).  Not only that, but when Glock sent my pistol back, they said they clean and lubed it...and I believe them.  It was very...non FrogLube feeling.  It was like completely dry, not slick feeling at all.  He cleaned it a little with a baby wipe and long q tip, greased the slide rails with Tetra.

So after the gun show we shot and I ran 100rds of the same PBR ammo, 10 rounds in the mags at a time, as I've been running.  1 FTF.  Prior to this I'd have had like 10 FTF.  Ran maybe 40 rounds of Underwood 135 and 165 grain.  1 FTF.  Made sure to save some spent brass this time.

He said the springs were supposed to be 6 inches long, starting from the point of the V on the first coil to the end of the spring.

One other thing that I thought interesting:  I don't know how pre-Gen4 mags go as far as the inner workings of the mag, however, he was paying particular attention to what looked like binding of my mags as they got up closer to the top of the mag.  He even went and checked another Gen4 G20 mag he had there, it did the same thing so he pronounced it normal.  But the reason he went and checked was because it did not appear normal to him.  I'd be interested in hearing from pre-Gen4 guys on how the piece the bullet sits on in the mag moves from say an inch from the top of the mag to the top of the mag.  Is there any binding or hangup at all?  It'd be something if these new Gen4 mags that are at least a little different in supporting ambi-mag release have some kind of imperfection in (some of?) them that is sometimes creating a less than smooth progression of the bullet upwards.  Might be another reason to explain why it's just us Gen4 guys having problems...

[4949shooter]

It sounds like instead of stretching your mag springs the armorer should have just replaced them.

[chucky2]

Might have been his thing, I don't know.  He certainly had a bunch of toolboxes there.  While I was waiting me turn for any of the problem guns that he looked it, it was something he did.  One dude had springs that were like 1/2 their normal size.  Lots of stretching on those...

[The_Shadow]

Just so you know it is not just the 10mm...look at this video, there is a lot to see and study with the dynamics!

[chucky2]

Wow...I never saw one of those videos before.  That frame flex, on a 9mm round no less, is nuts!  I wonder what a G20 would look like with something hot in it like 200gr Underwood...yikes!

[The_Shadow]

In this video, the ejector is not kicking the cartridge case up and out from under the extractor, so the casing is carried back towards the barrel with the returning slide.  At 0:50 you can see the next cartridge start to pop up, but the spent casing is not clear of the ejection port so it doesn't feed.  At 1:16 the cartridge has popped up and feed.

It seems that there is a problem with the ejector! Bent, broken or missing completely.  Was this done for the video?
The slide appears to be traveling all the way to the rear, to allow the spent casing to have engaged the ejector.

Then as the slide is moving rearward, the casing is hanging on by the extractor, till it strikes the ejector, it is at that point that the casing should be kicked to the right and upward and out from under the extractor to clear the ejection port.
In the video we don't see the casing exhibit this kick at all. 

So in conclusion, is the extractor the problem? I'd say no.  However, It is holding the casing, and the casing that fed does slide under the extractor, so it appears to fit.

Is the ejector the problem?  I'd say yes. 
This is not an ammunition problem.

Did you notice the slide lock as it is bouncing around?


I love the slow motion playback, you can learn a lot from these videos.

[Geeman]

Just so you know it is not just the 10mm...look at this video, there is a lot to see and study with the dynamics!

I want to call attention to the distance between the slide and the top of the frame right over where the magazine sits as the slide hits the end of its travel, especially the last shot shown 15 rounds).  Its that downward flex that I think is the issue with the Gen4 G20.  I think its made worse by the Gen4 sitting lower (web of the hand closer to the slide) and the increased pulse generated by Underwood and other high performance ammo.  That area flexes downward and takes the magazine with it.  The slide quickly returns under spring pressure and passes over the next round in the magazine.

That's what my issue is.  The slide rides over the top of the next round in the magazine.  Clearing it is just pulling the slide back and releasing it to chamber the round that hasn't left the magazine.

Greg

[The_Shadow]

Tested the Parabellum Research 165 grain FMJ V-Supreme ammo today, 50 rounds...

My back is still a little sore, it went out last Friday, weather yesterday was horrendous, over 4"+ rain yesterday.  Some of the ranges were closed; however I was able to get into one although it was sopping wet.  Wind was stiff and moving clouds made some shots not register on the CHRONY.

Here are the results of the range trip, Glock 20 SF.
NO failures of any kind.  I did fire 15, 5, 3, 2 from each of two different magazines.

Factory barrel/spring
1290, 1344, 1317, 1340, 1317, 1340, 1280, 1334, 1328, 1191,
1323, 1360, 1380, 1322, 1327, 1324, 1343, 1319, 1331

Factory Barrel Wolff Gun Springs 22lb non captive recoil rod and springs
1295, 1361, 1330, 1335, 1347, 1246, 1342, 1325, 1321, 1333,
1347, 1335, 1328, 1348, 1336, 1333, 1310, 1310

Those were the rounds that registered; I was sort of rushing through this, before anyone else showed up. 

Case expansion was 04330"- 0.4340", typical of Glock Factory Barrels.

No problems with this ammo as tested.   

[The_Shadow]

What needs to happen is for Glock to setup and observe these issues with the Glock 20 4th generations, using high speed cameras, playback in slow motion, and look for frame flexing, parts bouncing/moving under recoil or other induced stresses with real 10mm ammo, not the stuff at 40S&W ballistics.

I have to wonder if the "new frame design" that uses the various grip inserts, has caused a flexing of the frame with the higher impulsed ammo...   Is it flexing causing drag on the slide?  Looking for wear on the rails that the slide rides on, may not show up right away if the flex is bowing the frame up or down between the rails.

Then there is the current RSA which is also "new to the 4th Gen", is it part of the problems that so many people are having.
Is it enough for the control of the slide speeds?  Is it too much and causing a flex of the frame?

Why is it that the last round is staying in the magazine and not being picked up by the returning slide?  Is the slide stop not being held in proper location or is it bouncing at the time the round is trying to pop up, to cause the slide to lock open with rounds in the magazine. (BTW, this was noticed by S&W in their slow motion playback of video, during the development of the 10XX series.) 

There has to be a solution, to solve the issues being seen by so many Glock customers! 

The Gen 3's have run mostly without issues, my G-20SF has run flawlessly in stock configuration and with the Wolff 22 non captive recoil rod & 22lb spring, it has also run well with the LWD 6" 9x25Dillon barrel as tested also.

[ninja]

Now I'm thinking of curling my pinky finger around the mag base plate on both my G29 & G20 gen 4s' 

[The_Shadow]

However the main part of the testing was gun functions,  I shot singles, double taps and triple taps, testing for any failures that could possibly cause a stoppage.  However the Glock-20 SF pistol was flawless in stock configuration and with the use of the non captive Wolff recoil 22lb spring setup using different magazines, loaded with varying amounts of the ammo.

[ninja]

Looks like the flex is greatly reduced when the Glock is HANDHELD as illustrated here in this Smyrna GA take

http://www.youtube.com/watch?v=stGoVRKBU1U

What needs to happen is for Glock to setup and observe these issues with the Glock 20 4th generations, using high speed cameras, playback in slow motion, and look for frame flexing, parts bouncing/moving under recoil or other induced stresses with real 10mm ammo, not the stuff at 40S&W ballistics...

[4949shooter]

Looks like the flex is greatly reduced when the Glock is HANDHELD as illustrated here in this Smyrna GA take

http://www.youtube.com/watch?v=stGoVRKBU1U

What needs to happen is for Glock to setup and observe these issues with the Glock 20 4th generations, using high speed cameras, playback in slow motion, and look for frame flexing, parts bouncing/moving under recoil or other induced stresses with real 10mm ammo, not the stuff at 40S&W ballistics...

I believe that. My Glock fired fine with the stock spring and the high impulse ammo when fired one handed. It seems my wrist was able to absorb some of the recoil, whereas with a tight wristed two hand hold the frame absorbed the recoil and flexed.

[The_Shadow]

BTW, Today I submitted this to Glock Smyrna, GA. personally to fuel the search for a solution to the Gen4 problems...

I am a moderator on the 10mmFirearms.com website and frequent various other related sites and it seem there are many experiencing issues with the newer Generation 4 pistols.  My interest is with the Glock 20 gen4, trying to help people all over  understand/diagnose the issues they are  experiencing.

What I think needs to happen is for Glock to setup and observe these issues with the Glock 20 4th generations, using high speed cameras, playback in slow motion, and look for frame flexing, parts bouncing/moving under recoil or other induced stresses with real 10mm ammo, not the stuff at 40S&W ballistics.

I have to wonder if the "new frame design" that uses the various grip inserts, has caused a flexing of the frame with the higher impulsed ammo...   Is it flexing causing drag on the slide?  Looking for wear on the rails that the slide rides on, may not show up right away if the flex is bowing the frame up or down between the rails.

Then there is the current RSA which is also "new to the 4th Gen", is it part of the problems that so many people are having.
Is it enough for the control of the slide speeds?  Is it too much and causing a flex of the frame?

Why is it that the last round is staying in the magazine and not being picked up by the returning slide?  Is the slide stop not being held in proper location or is it bouncing at the time the round is trying to pop up, to cause the slide to lock open with rounds in the magazine. (BTW, this was noticed by S&W in their slow motion playback of video, during the development of the 10XX series.) 

There has to be a solution, to solve the issues being seen by so many Glock customers!  Glocks are great pistols but the latest gen4's have many disgusted.

The Gen 3's have run mostly without issues, my G-20SF has run flawlessly in stock configuration and even with the Wolff 22 non captive recoil rod & 22lb spring, it has also runs well with the LWD 6" 9x25Dillon barrel as tested also.  My G-29 also runs flawlessly.

Please find a solution to fix these great pistols...
Thanks,
Wade

I hope they can find a solution, that will be fixable / doable that will bring back the reliability to the Glock 20 Gen 4 pistols, its a shame that this is taking them this long to determine what is the casue and apply a fix for problems so many have experienced.

[mt10mm]

Hope glock will listen to what we have to say. Hope someone from glock comes here and pokes around.