Winchester 9MM NATO 124 GRAIN Q4318

I thought I had found my practice ammo for my G19.5, comped carry gun. I'm having a 2 to 4% failure to "Go Bang" rate. I've shot a couple of matches with this stuff. Runs the comp great, accuracy is acceptable, not super dirty but have two concerns after a 1000 rounds of this stuff:
Lots of brass in the striker channel
Cleaned that out and still have 2% failure to ignite.

Striker spring is factory
I do have a duty rated Overwatch Precision Tac trigger in it with a Ghost connector.

Would the connector contribute to lighter primmer strikes? Thinking that the NATO round has harder primers???

If it's not the gun, what other ammo would you run with the compensated gun? I still have another 2000 rounds of the Q4318. Note, it has made my failure / immediate action response quicker. Not a bad thing to train with, but absolutely not the ammo that I want to run at matches any longer.

So change something in the gun, or buy new ammo? Next thought process is Speer Lawman 124 grain, I can order a thousand rounds of that this weekend when I get time, but thought I would check out your thoughts on the gun set up first.

Full disclosure: G19.5, Zev Citadel slide, factory internals on the slide, RM06 on the top, X300U and I've already talked about the trigger.
Ran to the range tonight before dinner, ran MSP 3 and 2 drill from concealment, reloads, and draws from appendix. 150 rounds though the gun and only ONE failure to "go bang". 4% would have been 6 rounds, so 1 out of 150 is still .6 percent. More than I still want at a match, but not so bad for training ammo tonight.
Have you consider a heavy striker spring? To my knowledge and experience shooting 124 NATO they are heavier primers and I put the "Defensive carry striker spring" from ghost and I saw a decrease in my already super low Failure to Bang (FTB) rate.


Regular Member
You should not need a heavy striker spring in a Glock to shoot 9mm "NATO" spec ammo. The stock internals are designed for that.
The issue is Winchester's ammo, not your Glock.
I shoot tens of thousands of rounds of Speer Lawman (124gr and 147gr) without any incidents yearly.
In years past, for competition, I've shot 15000 rounds of Blazer in a season and had maybe two rounds not go bang. Jll2013, do you run a compensator on your gun with the Lawman 124gr?

I'm in a ammo pounding mode right now. The last few weeks have been 300 rounds plus a week. I'll keep the Winchester stuff and just say it's good for failure drills and buy some Lawman this morning for my matches. Last Tuesday night had 3 not ignite on one stage. NOT GOOD.
First you should narrow down whether it’s the gun or ammo.

Buy a similar loading from another manufacturer and run it through the gun as is and see what your failure is. The larger sample size the better, as I’m up to 1,000 rounds, not just 50, 100, 150, etc.

Second is replaced striker spring with a heavier one. Factory is 5.5#. Try a 6 or even 6.5#. Wolff and Ghost both offer them. A heavier one will make the trigger heavier too, and they don’t play well with lighter recoil springs.

I’m betting it’s the ammo and would start there, but it wouldn’t hurt to throw at least a new factory weight 5.5# striker spring in the gun for $3 worth of piece of mind.

Sent from my iPhone using Tapatalk Pro
A stock factory Glock will handle this ammo just fine. For trouble shooting elimination purposes, start with a thorough Armorer level detailed break down and cleaning, making sure to remove the firing pin assembly and thoroughly clean the firing pin channel and make sure you clean back side of the breach face well to make sure there is no build up of fouling or gummy lubes/solvents that are a possible cause of the issue. On reassembly make sure there is no lube in the firing pin channel.

Then try putting all stock Glock factory parts back in and see how everything performs.

The aftermarket slide could also be part of the issue if it wasn't machined correctly, which would allow the firing pin to move through the firing pin channel correctly, or won't let it protrude enough to allow reliable primer strike depth. If you suspect it might be the slide, for process of elimination try putting all the internals into a factory G19 slide and see what results you get. If you further suspect it's the slide, then get into contact with the manufacturer (Zev) and put it back into their hands.

Greg Sullivan "Sully"
SLR15 Rifles
(763) 712-0123


Regular Member
In years past, for competition, I've shot 15000 rounds of Blazer in a season and had maybe two rounds not go bang. Jll2013, do you run a compensator on your gun with the Lawman 124gr?
When I was running compensated Glocks (4 different pistols, all with KKM barrels and comps) I never had an issue with Lawman 124gr in any regard. I've also not had issues with Lawman 124gr having light strikes with three Glocks with aftermarket slides. That's for a total round count of 8000rds of 124gr Lawman and 1000rds of 124gr MEN.

I'm essentially shooting my Chambers Custom Night Fighter exclusively now (as far as 9mm pistols goes). No issues with 5000rds of 124gr Lawman and 1500rds of 147gr Lawman.
Just checked S&G and Lawman 124 is Out of Stock, found another place with good pricing, but $43 to ship a case - ridiculous. Thanks