Trigger Grit Fix?

[9x19MP]

Ok so I have my new to me M&P Full size 9 and I really love everything about it. The only issue is the trigger itself. I feel like the break is fine, and the reset is fine too, but better than I would have anticipated after reading some things online...the only issue is it sure is gritty feeling.

If I don't really want to change the trigger weight, what would you all suggest that I replace in it? Would simply switching to the Apex polymer "Glock" style trigger fix this? I feel like the grit is in the design of the pivoting trigger itself...or is there another part that causes it?

Thanks,
Josh

 

[GtownGeorge]

First step would be to polish the USB and trigger bar or buy a new one from APEX. That will smooth things out. The gritty feeling comes from the hump at end of trigger bar sliding up the usb.

 

[9x19MP]

I feel it now...I was just gonna say, it's NOT in the trigger, but during the pull between when the trigger is first pulled back until the break. So that may take some grit out? Is that hard to do? I have metal polish that I have used to like polish barrels before...Mother's mag...I'm assuming I'd just hand polish as to not remove any metal right?

 

[Gunhacker]

It's easy to do and will remove all of the gritty feeling. Use some 600 grit paper to remove the machining marks on the "ear/tab" of the trigger bar that engages the striker block, polish with the Mother's mag. It doesn't take much sanding... your goal is smoothing not removing metal.

Additionally, you can use a Q-tip dipped sparingly in Mother's Mag polish and smooth the shoulder of the striker block, the Apex USB version has the shoulders rounded, the factory shoulders are angular and if you knock the "knife edge" off the shoulders that makes for a better transition... like what you'd do to the top edge of a feed ramp going into the chamber.

Swapping the trigger with an apex one does nothing as you reuse the same trigger bar. But, I highly recommend the Apex Poly trigger, I like the solid feel over the 2 piece articulated factory trigger.

The poly trigger has rounded edges and feels like the glock trigger on the finger, the aluminum one has a squared edge, people that have them say they feel more like a 1911 trigger.

 

[GtownGeorge]

Google it, there are videos. Tough part is removing rear sight.

https://www.youtube.com/watch?v=6_r-J4zAJHo

 

[9x19MP]

Ya, removing the rearsight is something I'd love to avoid :/

 

[erick1987]

Dry fire it a couple hundred times. Or just shoot it. It clears up over time.

 

[B3500]

I bought the apex usb and it removed the gritty take up. This allowed me to swap it in and if ever need be can swap the original part back in.

Has S&W ever denied a warranty claim based on a person polishing any of the firearm's internal parts? I have read of that happening before, but have no personal experience if that is true fact or internet lore.

 

[Gunhacker]

I cringed watching that video... do the smoothing of the trigger bar in the area shown... that was a good explanation about how it engages the striker block and where the roughness on the trigger bar is at. Smoothing that area on the trigger bar is usually all that's needed to do the trick.

Or as mentioned... you can take the time and effort to dry fire (with snaps caps) or shoot a few hundred rounds through it, the parts will eventually "break in".

Not all slides have that burr, no need to routinely do that. Also... application of heat to loosen the red Loctite is correct.. but you don't want to be taking a torch to it indiscriminately.

As you see in the video... there are plastic/nylon parts close by... the end cap, the striker liner and that cap under the rear sight. Localized heat from the tip of a soldering iron tip held in the hex screw does the trick.

Flimsy masking tape on the end of a steel pin punch?

Of course it's going to mar the sight.

I went to a hardware store that sells short (hobby) lengths of 1/4" square brass rod and use that as a punch. The wider surface area of square rod distributes the force on the sight, is less likely to peen the sight like the small end of a pin punch, and with the force spread over a larger area it "motivates" it more. If the sight is too stubborn for that, it's best to stop and have it done by someone that's got a sight removal tool, lest you bung it all up.

 

[dullh]

The trigger grit question comes up every two weeks or so...with the subject coming up all the time with new members, shouldn't Apex kit information be a "sticky" post?

 

[9x19MP]

So I took the slide off, and had some 600grit laying around...it literally took 5 minutes. I got rid of the rough machining marks. Didn't even use any "polish" per se, but put a drop of oil on the sandpaper...it shined up smooth and bright. Reassembled, and I'd say 99% of the grit is gone. That is fine enough for me! I still like the idea of swapping the trigger simply because I've never been a fan of SW's pivoting trigger. I'm thinking I'll put the polymer apex trigger in, and take out the thumb safety (put in the plugs) and call it a done. (for now)

 

[dullh]

Has S&W ever denied a warranty claim based on a person polishing any of the firearm's internal parts?

If you, the user, mess with, polish or modify any factory parts, the factory can tell and your repairs will no longer be covered under warranty - that is true of all makes.

Drop-in replacement parts, however, shouldn't void the warranty - but don't be surprised if you send S&W a gun full of, say, Apex parts and find them all removed and replaced with factory parts when you get it back. If you're lucky, they'll return all the aftermarket parts they replaced, so you can put them all back in when you get the gun back.

 

[9x19MP]

The trigger grit question comes up every two weeks or so...with the subject coming up all the time with new members, shouldn't Apex kit information be a "sticky" post?

I did find alot on the kits themselves, but wasn't sure exactly which part would just fix the grit, without changing other factors. But I understand what you mean...or maybe a "common modifications" sticky?

 

[dullh]

Dry fire it a couple hundred times. Or just shoot it. It clears up over time.

No. It doesn't.

 

[dullh]

I did find alot on the kits themselves, but wasn't sure exactly which part would just fix the grit, without changing other factors. But I understand what you mean...or maybe a "common modifications" sticky?

It would be a good idea for a sticky.

The part that causes the grit, you found, is the USB in the slide. You worked on it, and if the trigger pull is now up to par for you, you are good to go. If not, then the Apex USB is the only part you really need to get; by itself it's only about $26 or so.

The big pain is replacing the USB...in order to do so, you have to remove the rear sight. No problem if you have a sight pusher tool, kind of a drag with a vice and punch...

 

[erick1987]

No. It doesn't.

Huh. Mine did.

 

[rdtompki]

I just replaced the USB on my 40fs (part of DCAEK). The "hardest" part is finding a 1/16" hex that fits the set screw well enough. I used a soldering iron tip to heat the screw slightly to help with the red loctite. Although I had purchased a sight pusher, the sight didn't take much of a push; a soft punch would, I believe, easily have done the job. When I replaced the screw I used blue loctite. FWIW the DCAEK dropped the trigger pull from 7 to 6 lbs with a much shorter reset.