M&P 9mm Full Size trigger clicking

[McNick]

I purchased an M&P 9mm full size a few months ago. I have fired about 600 rounds through it so far. When I bought it, the trigger had a slight "clicking" to it. I was hoping it would go away by now but it's still prominent. Has anyone else had this issue and if so, how did you resolve it?

 

[Bkreutz]

I purchased an M&P 9mm full size a few months ago. I have fired about 600 rounds through it so far. When I bought it, the trigger had a slight "clicking" to it. I was hoping it would go away by now but it's still prominent. Has anyone else had this issue and if so, how did you resolve it?

Need more information, when you're pulling the trigger or releasing it. I never hear a clicking, all I hear is a loud "bang" when I pull the trigger.

 

[MichiganScott]

Sounds like the reset to me.

 

[robkarrob]

Where is it clicking? If right after you start pulling the trigger back, it is likely the drop safety. The lower half of the trigger is hinged, and on the other end is a lever that sticks out from the rear of the top section of the trigger. The lever and hinge is to prevent the trigger from moving if the gun is dropped and the gun hits hard on the back area, direction that the trigger travels.

What happens often is the as you pull the trigger back, the lever is not clearing the slot in the frame and is hitting the frame, causing the clicking sound. You can easily file off a small amount from the upper lever, so it no longer contacts the frame.

If this is not the issue we need more information as to where in the trigger pull you are having the click sound. Clicking just before the break, after the break, when releasing the trigger forward, etc. Remove the slide and see if the click goes away. If not it should be much easier to determine where the click is coming from.

Bob

 

[McNick]

It's not a clicking that I can hear, I feel it when I pull the trigger about a quarter of the way. It doesn't affect my shot, it's just not as smooth as I would like it to be or that I would expect...

 

[Prasko]

It's probably the trigger bar hitting the striker block.

 

[Llando88]

Maybe take the slide off, see if the clicking remains? Could be a way to isolate where the 'click' is...?

 

[rsrocket1]

If you are feeling a "gritty" trigger pull, you may be feeling the trigger bar going across the striker block (in the slide). The original striker block has hard edges on it and as the top of the trigger bar presses against the striker block. The arrow points at where the trigger bar moves against the striker block

Shown below is a picture of the original striker block and the Apex Ultimate Striker Block (USB). See how the original one is angled while the USB is more like a dome?

The original one came out of my gun after 20,000+ rounds so it is pretty smooth, some blocks have very pronounced edges.

As you shoot it, the edges wear down and the "grittiness" goes away.

If it's something else, try to describe the feeling in a little more detail.

 

[krieger]

- all of the above

 

[jimbovia]

As this is one of the few articles on this subject that isn't dead or severely aged, I want to provide some additional commentary in the hopes that the conversation might continue.

I've been using this and a few other articles/posts as a reference in my efforts to eliminate the gritty trigger pull on my M&P 40 Pro. I assert that the gritty trigger is likely caused by the manufacturing process (such as a worn cutting bit) as my earlier M&P 9 Pro doesn't show any of the same symptoms. Although the striker block and trigger bar surfaces clearly cause some of the unwanted feel, after having now spent two days slowly cleaning things up, I can with 100% certainty say that these surfaces are not the sole cause. It is my opinion that the cut/tube/channel in the slide that the striker block rides in is the primary culprit. I can't for certain say that there is a burr that others have said is the cause, but there is clearly a roughness.

For anyone that has ever polished metal, the initial polish actually exposes visually some of the roughness that can only be felt for the most part prior to the first polish. I suspect that just like flat metal, cylinder cuts also have this same roughness. As that cut/tube/channel is roughly .255", I haven't yet found a safe means to polish it in one clear process. I am trying some small soft rubber polishing bits, but for obvious reasons am limiting how much I work the area.

On the striker block, reshaping/rounding the radius edge and polishing did make some difference. After this didn't completely remove the gritty feeling completely, I investigated the movement of the striker block in the slide. With the rear sight removed and applying some pressure to the striker block while moving it up and down in the slide manually, I can feel the same gritty edge feeling.

More to come as I make progress.

Regards,
Jim

 

[jimbovia]

So, I pulled the trigger (figuratively speaking) on ordering small felt polishing mandrels (i.e. will work in a Dremel) that will fit into the hole where the striker block is. Hopefully they will be here next week and I can proceed with my experimentation in polishing the walls of that hole.

to be continued....