G17 - Trigger Reset Issue

[cferree]

I have a Gen 3 G17 with a trigger reset issue.  I’ve searched this forum and others with no definite solution found.

It’s a CO gun with a ZEV Dragonfly slide (this issue is slide related – it does not happen with the factory slide).  The trigger will reset to the front, but doesn’t “catch” the striker.  I cannot duplicate this with dry fire (slowly letting the slide forward or letting it slam into battery).  It does not do this consistently.  Last Friday it ran fine for a 300+ round practice session, and didn’t reset at least 10 times during a 6 stage SCSA match on Saturday (same ammo).

Here’s the combination of fire control components I’ve tried with no solution found:

Zev trigger with Zev connector –Strikers (2 different Zev Strikers & a Factory Striker)

Factory trigger with “-“ Glock connector - Strikers (2 different Zev Strikers & a Factory Striker)

Factory trigger with Lone Wolf connector - Strikers (2 different Zev Strikers & a Factory Striker)

 

The Slide is the common denominator.  Is there any way the Channel Liner could either be too long or not installed completely?  Because of this the Striker can’t come completely forward (consistently), therefore Striker doesn’t reset.

 

I’m not wasting my time contacting Zev.  I’ve been on a waiting list for frame work for three years and have never been contacted.  This slide had burrs in the Extractor tunnel from the drilling and tapping of the slide for the optic mount.  I had to run a needle file down the channel to clean it up so the Extractor Bearing would move freely.  This equates to little or no QC.

 

Any suggestions on possible solutions would be greatly appreciated.

 

 

 

 

[Aircooled6racer]

Charles, check to see if the sleeve is installed all the way in. Also check the striker to see if it is similar to the original and not a later gen. If you can do some measuring to see if it is like the original Glock slide. I should be at Cherokee this weekend if you want me to look at it. On a side note my Brownells RMR slide is working great on my Gen 2 G17. I just thought of something else change the striker spring and recoil spring to stock and see if it works them. Thanks, Eric

[sigsauerfan]

do  you use  the same  striker i for  both slides?

 

it is  possible  that  for  some  reasons, the  striker  leg  (the  part of the  striker engaging the  cruciform tab of  the  trigger  bar)  sits  lower  in the  dragonfly than in the  oem slide...then,the leg  doesn't  emgage  the  tab of  the  cruciform  consistently. the cure  for  this  problem   would  be  bending the  tab   in  the  UP  direction so  it  engage  the  striker leg correctly. it's  a  matter  of  MICRONS. you don't  want  to  really  bend  it  more,just applying  a  moderate  pressure  to  set  it   couple  microns   higher.  ;   ,it's  a  matter  of  couple  microns ,NOT   millimeters .

 

all my  limited  glocks  gets  the  zev  ultimate  trigger   kit  treatement,still,i  work them  a  little  more,and  on some  occasions,i   went  too  far,  with  the  same  result  as  what you  experience  right now...and  i  used  this  trick  i  mentionned  to  correct  the  problem  i  created  by  reducing  the  striker-cruciform engagement  seeking  a  lower   trigger  weight  break.

[edison]

I'm with Aircool; try the stock factory striker spring with the stock striker & stock cups. Make sure the cups halves aren't splitting under the spring pressure.

This should overpower the imperfect/rough channel liner. If that works, then you can get a replacement channel liner from lonewolf.

Edited January 9, 2019 by edison

[cferree]

All three trigger groups get the results with a factory striker group (striker, cups, spring, etc.) and two different Zev Strikers and Zev Springs.

I tried 9 different combinations of trigger groups and strikers.  Eventually, I'd have a failure to reset.

 

I'm going to double check the Channel Liner (make sure it's fully seated - it was install by Zev).  I've got spare liners.   If it doesn't match the factory slide, I'll pull it and replace it.

If this doesn't work, I'm going to try sigsauerfan's suggestion.  This is has to be caused by dimensional differences between the slides, if it's not the Channel Liner.

 

FYI, 500 rounds thru the fun with the factory slide using a Zev trigger / Zev Striker and a factory trigger / Zev Striker ran without issue.

[rooster]

Don’t think it’s liner because I ran a 17 without one for a short while.  I got my pistol back from having my slide milled for optic and black nitride.  There is a step in the liner Chanel that looks like it was installed. The way I found out it was missing was the check where when you hold the  back trigger the firing pin should rattle in slide.  You can buy a tool or use a 5/16 lag bolt to remove.  When I tried to remove nothing would come out so I tried to install one and it went right in. Like a few people said I would try bending the cruciform leg a tiny bit.

But be careful they are extremely hard and easy to break. 

[Aircooled6racer]

Charles, do some measuring on the Zev slide compared to the factory slide to see if they are different. I would agree the trigger bars are heat treated and are very hard so be careful if you try to bend it. Thanks, Eric

[dskinsler83]

It is the slide and how it fits the frame along with the tolerances of the maching. You will have to adjust the angle of the sear.  Use an armoers plate to check how much engagement you have. Id almost bet it is less than half.  Also if you have to much pre travel removed it can cause the  trigger bar to “bounce” off the striker causing a dead trigger

[dskinsler83]

And yes you do have to be EXTREMELY careful when bending them. 

[JBP55]

Use Heat and Go Slow.

[Aircooled6racer]

Charles, did you ever get this figured out? Thanks, Eric

[cferree]

Update:

After doing measurements for an hour+, I found that the Zev slide sits approx. 0.010" higher than the factory slide.

 

Depending on what combination of parts I used, I was only seeing 30-50% engagement between the trigger bar and striker (thanks DK for reminding me to use the Armorer's back plate).

 

So...I heated one of the factory trigger bars and using a vice, a set of pliers to help stabilize it and an adjustable wrench to do the bending, I now have 100% engagement with that bar and one of the Zev Strikers.

 

I'll test it at the range tomorrow.

 

Thanks for all the suggestions.

[Furrly]

There is your Problem, ZEV!!!!, return everything back to stock and your problem will go away..it's a  harsh reality...good luck

[cferree]

Show me how to get a G17 slide down to 8.5 ozs with a cut for a DPP, and I will.

Until then I make this one work.

[dskinsler83]

You are welcome!  Hope it works out. 

[JBP55]

4 hours ago, Furrly said:

There is your Problem, ZEV!!!!, return everything back to stock and your problem will go away..it's a  harsh reality...good luck

 

 

Funny!

[Paul49]

Why does the slide need to lose weight beyond the cut for the DPP?

 

I put a DPP on my G35 using a Dueck Defense dovetail mount, kept the same factory recoil spring weight and everything worked fine. No slide cut and the added weight of the dovetail mount.

 

Then I decided to move the DPP to a Carver Custom frame mount so it no longer reciprocates. I left the slide without front or rear sights and still kept the same recoil spring weight and everything still works fine.

[Aircooled6racer]

Hello: He is using it for Steel Challenge, so the lighter it is the faster transitions to the next target. Thanks, Eric

[Jamese35]

Did you try calling ZEV? I've been hearing nothing but bad from ZEV lately. QC seems to have gone down the drain, triggers that are not drop safe and bad milling. It's a shame that this stuff happens. I looked at having them build me a limited gun but went to DCPrecision LLC do to the leadtime and they wanted way more for way less of a gun then I have coming. 

 I wonder if the striker channel is milled just a hair higher then it should be?

[cferree]

Update #2:

I shot a 200 round practice session today without any trigger reset issues.  I did have 4 light strikes, so it's time to take a look at the striker spring.

I shot another 300 rounds of the same ammo thru a SA SS 9mm I'm working on for a Limited SCSA gun without issue.  So it's not the ammo.

I think it has a 3 lbs striker spring.  If it is, I'll try if with a 4 lbs.  If the light strikes continue, I'll put a factory spring in it.

 

As to the slide weight, why wouldn't you run the lightest slide possible without sacrificing durability?  We're racing guns.  And I'm shooting a 115-118 PF load.

 

Jamese35, I believe you right.  Either the striker channel is bored high or the channel bore to rail location is high, or both.  Without an surface plate and a dial indicator, I can't get any closer with my measurements.  You are also correct about the lack of QC at Zev.  The extractor hole had a bur left over from drill and tap for the optic mount.  It was so bad, the ejector bearing wouldn't go but half way down the hole.

 

The measurements don't matter as much now that I found that the issue was lack of engagement (per DK's suggestion).  The heat and bend cured that and induced the light strike issue.  A spring change will resolve that problem.

 

 

Edited January 19, 2019 by cferree

[dskinsler83]

I would say that the heat and bend induced your light primer strikes. 

 

Im gonna get on a bit of a tangent here and please do not take it personally.  One can NOT compare the firing mechanism of a Glock to another pistol, especially a hammer fired SA pistol.  I have said it so MANY TIMES to customers who contact me wanting a “as close to a 1911 as you can get” trigger.  It is a GLOCK not a 1911/2011 or any other 11.  A Glock mechanism has to HAVE movement in ALL directions of design to function properly.  The is no magic voodoo this  trigger has no pre or over travel what so ever Glock trigger out there, if it is claimed, well then something somewhere isnt working correctly.  Namely the drop and FP block safeties.  

 

Ok. Now sorry but had to say it.  On to the ammo, is it factory or reloaded?  Primers if reloaded?  Machine used to reload them?  OAL of reload?  

 

Also be sure you do not have to much over travel removed.  You should be able to shake the pistol with striker down and here it hitting the breach face.  If not then you are not getting the FP block out of the way sufficiently. This causes the striker to hit the FP block eventually rendering it useless by damaging the shoulder and damaging the grooves of the strikeread on the right side.  The Glock striker works off of power of the spring being compressed, if anything adjusting the angle to increase the engagement has created a greater compression than to less of one as it has further to move until it releases.  A SA pistol like a 1911 on the other hand is driving a firing pin into the primer by striking it, usually by way of at minimum a 17lb main spring, which is what 13lb heavier by comparison. 

 

Check the ammo, check the firing pin and fp block, check to be sure your ogive of the bullet is not hitting the rifling causing slightly out of battery conditions, oh and last but certainly not least check the spring cups.  Misaligned spring cups can cause drag in the liner, be sure the end of the striker spring is not splitting the cups, turn the cups to keep a solid area over the ending of the coil. 

 

Hope this helps. 

 

Regards,

DK

[cferree]

DK,

The ammo is loaded on a 1050 and QC'd with a Shockbottle ammo gauge.  I check it for OAL (1.125 for this ammo), bad cases/bad crimp, and primer seating depth.  This ammo passed.  The primers are CCI.  I've shot 10-15K thru this 17 with the factory top end. 

 

The trigger is factory Glock, so no over travel or pre-travel screws.

 

I need to check the Striker for freedom of movement.  Same for the drop safety movement.  I did make sure the cups weren't aligned with the end of the spring.  I learned that lesson years ago.

 

And I'm fine with a "Glock" trigger being a Glock trigger.  I've shot them since the mid 90's and never saw the need for a 2 lbs, no pre-travel, no over travel trigger.  To be honest, this CO gun is a low cost bridge while I build a SS Open 9mm for SCSA.  It will also get shot at the occasional USPSA match.  So I'm after 99% reliable, not a 1911 trigger in a Glock.

 

And I don't take advise/suggestions from experts personal.  I appreciate someone who generates income from their expertise, giving it away for free.

Edited January 19, 2019 by cferree

[dskinsler83]

Is it a factory striker?  I was thinking it wasnt 

[cferree]

Striker is a Zev.  Should I try a factory striker and factory spring?  The drop safety and spring are also Zev.  I've got a factory and Lightning Strike I could use.

[pskys2]

Start with all factory parts in the Zev slide, including all springs (striker, fp block and trigger).  Then start adding parts back in piece by piece with springs being last.

If it won't work with all factory parts including springs in the Zev slide, the slide is compromised and would likely need the attention of a competent glock smith.

Doesn't sound good for Zev does it?