M&P Gen 1 dead trigger

First disclaimer, already working with APEX customer service.

Gun. M&P Gen1 9mm.
Installed: Apex forward set sear w/spring
Apex flat faced trigger
Stock trigger return spring
Stock striker assembly
Apex ultimate striker block
Apex semi-drop in barrel
M&P CORE Ported Slide Kit
Leupold Delta Point Pro optic
13 lb recoil spring, tungsten guide rod

Problem
At some point a round will chamber but trigger will be dead. Very random. Have adjusted the trigger loop from initial sizing of .009 to .012 to .015 to approximately .018. per the Apex instructions to allow more over travel. Gun works perfect in dry fire. In the process of replacing the sear housing block and the sear spring. Not sure that will fix the issue. It so random, that I shot practice last Saturday, approx 250 rounds, with no issue. Shot USPSA match on Sun, dead trigger 3 times during the match. Can not replicate the issue. It just "happens". Local gunsmith's only advice to go back to stock. As a comp shooter, that is not an option.

Gun did not have this issue with the standard Apex kit, trigger, sear, striker block. Only happened with the forward set kit, and only after about 1000 rounds.

Any thoughts would be helpful.

I wonder if there is something in terms of debris that you cannot see or clean that could be remedied by a partial or full disassembly and subjection to a thorough ultrasonic cleaning? Old lubrication and crud can creep into parts unknown and cause intermittent problems. Just a thought.

I had this same problem on a full sized Gen1 M&P 9 that I installed the Forward Set Sear Kit in for another gentleman. I have installed at least 18 -20 of these kits without a single problem but this one about drove me nuts. I tried everything. I put his kit in my gun and it would work. Put my parts in his sear block and it would Fail to Fire. Best I could tell it was a timing issue with the Striker Safety interfering with the striker. I even purchased and replaced his trigger drawbar with the latest model to eliminate that issue. Finally got 100% ignition by closing the loop completely and started opening it up a couple thousants at a time. HOWEVER, I did get a call from the gentleman again a couple weeks ago and he was again experiencing random failures to fire. My only suggestion at that point was to contact APEX and see if they could take a look at what was going on. I believe that there is a stacking of tolerances that occurs whereby unless you have a box full of parts to work from some guns just seem to be a problem with the Forward Set Sear.

mckenney99 said:

I had this same problem on a full sized Gen1 M&P 9 that I installed the Forward Set Sear Kit in for another gentleman. I have installed at least 18 -20 of these kits without a single problem but this one about drove me nuts. I tried everything. I put his kit in my gun and it would work. Put my parts in his sear block and it would Fail to Fire. Best I could tell it was a timing issue with the Striker Safety interfering with the striker. I even purchased and replaced his trigger drawbar with the latest model to eliminate that issue. Finally got 100% ignition by closing the loop completely and started opening it up a couple thousants at a time. HOWEVER, I did get a call from the gentleman again a couple weeks ago and he was again experiencing random failures to fire. My only suggestion at that point was to contact APEX and see if they could take a look at what was going on. I believe that there is a stacking of tolerances that occurs whereby unless you have a box full of parts to work from some guns just seem to be a problem with the Forward Set Sear.

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Thanks for the input. I did just get another trigger bar from Brownells. The "H" bar rather than the "S" in my gun. Might try that if the new sear housing block assembly doesn't do anything. The part that is a pain, is that it is so random. It's an hour to the range to test (because it only happens in live fire). Shoot fast, shoot slow, trap the trigger, don't trap the trigger. It makes no difference. Heck, I would send it to Apex, but it may shoot perfect for them, and then come back and fail for me.

armorer951 said:

I wonder if there is something in terms of debris that you cannot see or clean that could be remedied by a partial or full disassembly and subjection to a thorough ultrasonic cleaning? Old lubrication and crud can creep into parts unknown and cause intermittent problems. Just a thought.

Click to expand...

It is worth a try. Thanks for this.

If you return all parts back to stock and it runs flawlessly, then it is telling you that the aftermarket parts in some manner or combination are the source of your problem.

I also shoot USPSA and do so with a totally stock gun. Would rather have total reliability over having a tricked out trigger that isn't.....

Randy

Forgot to mention couple things with the problem gun I tried to install the Forward Set Sear in. I NEVER could get the gun to work at all with the Apex striker block. I believe the rounded edges of the Apex block was causing some of the striker timing issues this particular gun was having. With the problem gun I even tried another Apex Forward Set Sear kit that I had on hand & had never used. Still random failures to fire. By the time I was done I came to the conclusion that the sear block in that particular gun may have been the issue and I didn't have any different ones to try. I did finally get the problem gun to finally fire reliably using the factory striker block. Inorder to see if I was losing my mind, I took all the Apex Forward Set Sear Kit parts left over from the 2 kits and installed them in my own Gen 1 5 inch 9mm Pro model with NO adjustments and that gun has functioned flawlessly for several hundred rounds. Go figure.

northbay shooter, just read your post for the forth time and I may have misread your problem. When you say you have a "dead" trigger, is the striker not being caught by the sear or are you getting light strikes on the primer, indicated by a very light dot or "tap" on the primer?

growr said:

If you return all parts back to stock and it runs flawlessly, then it is telling you that the aftermarket parts in some manner or combination are the source of your problem.

I also shoot USPSA and do so with a totally stock gun. Would rather have total reliability over having a tricked out trigger that isn't.....

Randy

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When I shot production, it was just the normal Apex parts. I didn't do the forward set until I moved to carry optics. However, I totally agree. Last weekend, it cost me some points and a couple of mikes on movers.

mckenney99 said:

northbay shooter, just read your post for the forth time and I may have misread your problem. When you say you have a "dead" trigger, is the striker not being caught by the sear or are you getting light strikes on the primer, indicated by a very light dot or "tap" on the primer?

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There is no primer strike. It is just like you didn't rack the gun but there is a round in the chamber. I think your thought about the striker block could be right on. I thought about that too but was assured by Apex you need their USB with their sear for function. New springs arrive tomorrow. Will do the change out and go to the range.

Quick update
Thanks to everyone for the suggestions. Yesterday, new sear spring arrived from Apex.

Replaced the sear housing block
Replaced the sear spring
Replaced the striker assembly

Cleaned everything while apart. Gun feels good, but it has always worked in dry-fire. Will shoot it at the range this weekend and see.

Having a light/no strike with the striker falling forward is a different problem than the striker not being caught by the sear during recoil/cycling (resulting in a "dead trigger", meaning no striker fall - because it was never caught by the sear - so there's no resistance felt during the trigger pull).

In the original standard M&P sear blocks (except for the MA compliant sear blocks) the sear spring and plunger were itty bitty. The revised standard blocks allowed for the larger MA-type plunger and spring to be used. This larger spring and plunger might be better able to power the sear lift when fouling gets bad. (The original MA-compliant "trigger" involved the use of a heavier sear plunger & spring, a heavier trigger spring and a steeper candy cane/loop angle on the trigger bar, according to what I was told as an armorer.)

Original standard sear block, sear plunger and spring on left, with MA-type and new standard plunger and spring, in a MA-compliant sear block on right:




Now, in light strike conditions it's reasonable to start looking at the clearance/timing of the striker safety block. FWIW, a friend just one of his M&P's back from the PC, and they installed a different rounded shoulder safety block.

Now, I can't pretend to know what's happening with the OP's M&P because I not only can't see and examine it, but it's been modified with Apex parts to be run as a game gun.

However, if the trigger is "dead" in the respect that the sear isn't catching and holding the striker during live-fire conditions (speed of cycling and shock of live-fire), and there's no resistance in the trigger pull (because the trigger's candy cane/loop isn't being pushed against the lowered sear nose) ... it's a different problem than the striker being caught by the sear and experiencing some interference when being released to fun forward.

Gotta identify the problem - not just the symptom - before you figure out how to correct it. Sometimes trying to "fix" a symptom can have you chasing your tail because you haven't actually identified the underlying problem causing the symptom that requires correction. BTDT.

Luck to you. Just some thoughts.

I have this kit in my 9L as well. I have never experienced a "dead trigger" but I do get random light strikes. I've gone to only using Federal primers with my M&P. Today I shot a steel match and used the Syntech 150 Federal Competition rounds and had no issues. They shoot very close to the rounds I reload on my own so they were good to go. If I can get may hands on some Federal primers I'll be using those for my M&P rounds. CCI primers work fine with my CZ Shadow 2.
I'd love to know why this kit is problematic. I have a 2 pound pull literally no take up and a very short crisp reset.
When it's working , it's an awesome trigger.
My stock Trigger worked flawlessly, it just wasn't anywhere near a "real competition" trigger, like it is now.

kmanick said:

I have this kit in my 9L as well. I have never experienced a "dead trigger" but I do get random light strikes. I've gone to only using Federal primers with my M&P. Today I shot a steel match and used the Syntech 150 Federal Competition rounds and had no issues. They shoot very close to the rounds I reload on my own so they were good to go. If I can get may hands on some Federal primers I'll be using those for my M&P rounds. CCI primers work fine with my CZ Shadow 2.
I'd love to know why this kit is problematic. I have a 2 pound pull literally no take up and a very short crips reset.
When it's working , it's an awesome trigger.
My stock Trigger worked flawlessly, it just wasn't anywhere near a "real competition" trigger, like it is now.

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I couldn't agree more. When it works this trigger is perfect. It is as close to a 1911 trigger as you can get in an M&P. According to Apex, the tuning is the critical aspect of the flat face trigger on the forward set sear. Everything is happening in a short amount of space so it needs to be perfect. The ideal would be to do the tuning work at the range where you can take the gun apart, make adjustments, and shoot it. I can't do that where I live, so it is at least a day or more before I can test the changes.

I have not had any light strikes, just this dead trigger. I just wish it was not so random. If there was some pattern, it might be easier to fix or to tell Apex about. Like I mentioned before, it does not matter. Fast or slow, trap the trigger or don't, full mags or almost empty, clean gun or dirty.

If your striker is not being caught by the sear then as fastbolt stated that is a different problem than a light strike. I had a friend with a .40 Shield in which he had me install an Apex carry/duty kit. After many thousands of rounds, he started to get random occurrences of the striker failing to be caught by the sear, not light strikes, the trigger wasn't being reset at all. He finally called Apex and got a couple new sear springs, he installed the new sear springs and the problem was completely solved. Figure the weakened sear spring was unable to keep up with the cycling slide and the sear was not catching the striker.

ok you may want to look into this as well. I was shooting my 9l today at the range. I cannot get the trigger to go dead no matter what I do. I let 2 other people shoot it and they both experienced the "dead Trigger". I took the gun out of my friends hand and noticed that it had not gone all the way into battery. I did a tiny press check and the round fired. I notice that every time this happens the strike is up near the top of the rim of the casing. I looked around online and found others that had the same problem. Never on the first shot , but on a following shot. I'm left handed so my grip never interferes with the slide, my friends are right handed and it happens to them all the time. Riding the slide? pressing against the slide stop? I don't know what they are doing , but I don't. I shot a steel match with it yesterday, 150 rounds match and I had zero issues.
To see it happen twice today by 2 different people, when I can't make it happen really opened my eyes. if it happens again just move the slide back a tiny bit and then press forward and see if the round will fire. I'm only using federal Primers with mine now and not experiencing any light strikes either.
I hope this is your issue, if it is check your extractor for any burrs and use grease on the rail instead of oil and slide rack the **** out of it . it should loosen up I changed my barrell to a KKM barrel as well, I need to take my friends out and let them shoot it with the stock ported barrel as well and see if maybe the barrel is the issue(I changed the trigger and the barrel at the same time)

If the slide/barrel is slightly out of battery, by design the trigger is supposed to be "disconnected". That's how it works.

However, if the slide is being impeded from returning fully forward into battery, and thus being in-battery, then the common causes to consider would be the shooter (grip stability robbing force from recoil spring), the recoil spring (damaged/weakened) and/or the ammo (power level problem or physical spec of assembled round).

Latest update -
Finally got to the range yesterday. Gun ran perfect for a couple of hundred rounds. Not that it means anything since it's done that before. Shooting a local match tomorrow as last tune up before a state section match next next weekend. Fingers crossed the problem is fixed.

Gun has been completely cleaned. New sear housing block, new sear spring, new striker assembly, new back plate. Gun feels really tight because of the new housing block. The only thing really left to try would be to change the recoil spring from 13# to 15#.

Final Post
It seems like the gun is fixed. Shot a match today and the gun ran flawless. Even with some very fast splits. I think it was either the sear spring worn out (now fixed with a new replacement) or some slight movement on the sear housing block in recoil (now fixed with a new replacement). Either way, gun is awesome again. Now if I can shoot better....LOL.