M&P45 1.0 Occasional Dead Trigger

[revchuck38]

I dug out my early-production full-size M&P45 to give myself a change from shooting my TDA guns. The last time I shot it, there were a couple of times where I pulled the trigger and nothing happened, but I put it down as not letting the trigger reset due to shootig my PX4s so much. This time I often couldn't get through a full magazine without it happening. When it happened, I'd have to take my finger completely off the trigger and press again once or twice to get it to fire.

Since I'm a complete moron when it comes to gunsmithing, I've never detail-stripped the gun, just field-stripped it and cleaned it as well as I could. Once or twice I've sprayed the inside out with Gun Scrubber. The gun is completely stock. These last two range sessions are the only times it's hiccuped since I bought it new probably ten years ago. It's got ~5k rounds through it.

Suggestions?

[ranger]

If you search internet for "S&W M&P dead trigger" you will see numerous discussions on the issue in older M&Ps. Several reference the "old style sear spring" as the issue. For M&P maintenance - the APEX tactical videos are your friend! You can strip that M&P down with a punch.

[revchuck38]

ranger - Thanks for the tip. I searched on that phrase and it appears this is common with the early ones. It also looks like S&W will repair/upgrade it under warranty. I'm going to email S&W and see what they say. I really like the gun and don't mind the stock trigger, so that's the most cost-effective way if they'll do it.

[Spartan1980]

With 5K rounds thru it, I'd bet on grunge built up under the sear and perhaps impeding that tiny ass little sear spring's movement. It's easy to take out and clean but whatever you do don't turn it upside down lest it'll make a run for, and in fact, obtain freedom. S&W won't send you a new spring as it's considered a fire control part. Ask me how I know...

Also I have a 9Pro (early 1.0 vintage) that had the dead trigger thing. A very, very slight tweak bending the trigger bar away from the frame fixed it.

[JAH 3rd]

I know S&W upgraded their sear spring at some point in the 1.0 lineup due to issues with a dead trigger. They used a heavier spring to address this issue. I don't know where you could find just the upgraded spring, but you might try your favorite search engine to locate one.

[revchuck38]

That's a possibility, but I'm waiting on a call tag from S&W so I can send it back to the mothership and let them fix it. That way there's no possibility of me screwing it up. :)

[mmc45414]

I don't know where you could find just the upgraded springThe spring was larger and requires the newer striker block. For a while they were available, not sure still?

[Wendell]

Brownells has the magazine-disconnect version:

940-001-017WB
Sear Housing Block Assembly, NMS, MAG SAF Mfr Part: 393760000
SMITH & WESSON

https://www.brownells.com/schematics/smith-wesson-/mp-semi-auto--sid859.aspx#r25sid859


https://www.youtube.com/watch?v=QzTz5v4VsQU


https://www.youtube.com/watch?v=zMLv_JaoSkU

[revchuck38]

The call tag came, so tomorrow it's off to Springfield.

[revchuck38]

And now it's on its way back home, due here on Monday. A three-week turnaround isn't bad, especially since that period included Thanksgiving week. I was expecting an email saying either yes, it's a warranty repair or requesting my credit card info, but only got the notification that it's on its way. I can use the money for the PC trigger job on something else, probably sights.

[revchuck38]

I received it yesterday, made it to the range this morning to test it. I put 100 rounds through it including 12 of my carry load (230 grain +P HST) and it ran flawlessly. The paperwork said they replaced the trigger, and there is a new trigger in it, less mushy than the original. Wonder if I got an upgrade to the 2.0 trigger?

I was reminded how nice it is to shoot a 45, and how damned accurate that gun is.