Smoothing out a trigger ...

[Jim2527]

Everyone's favorite topic. Its well established what the flaws are and how to correct them. But there's more to it than throwing a new trigger. Here's what I did.

1. Smoothed the trigger bar surface where it interfaces with the striker plunger
2. Smoothed the striker plunger hole
3. Smoothed the sear actuator
4. Smoothed the trigger bar side against the frame.

By 'smooth' I mean removing the absolute minimum amount material by sanding with progressive grits then polishing. For sanding I use finger nails files unless I need something very course then its regular paper. Black, white, pink, blue nail files/buffers. For polish I use Simichrome but any of the known products work..Flitz, Mothers aluminum polish.

3 pics of the trigger bar:
Pic 1 shows the factory finish. Its not overly smooth
Pic 2 shows the bar after a few passes with 180 grit paper. Its now very easy to see the uneven surface
Pic 3 is polished up. I didn't smooth it completely flat as I didn't want to remove too much material

2 pics of the plunger hole:
Pic 1 I wrapped machine screw with 2000 grit paper and made a few passes with the drill set at moderate speed
Pic 2 is after

 

[jurek]

Great job.

What about the plunger itself? Did you polished its head as well?

 

[Jim2527]

Great job.

What about the plunger itself? Did you polished its head as well?

Yes. I made a slight contour change at the shoulder then polished the entire plunger. After all the polishing, a single drop of lube, as indicated in the owners manual, is still needed on the trigger bar / plunger interface. Without that drop its metal on metal.

 

[jurek]

Sounds like you did a really great manufacturing.

I did polished my M&P9 internals, but I didn't want to play with plunger and used APEX whole set.
Your work looks $160 less expensive

 

[Jim2527]

Sounds like you did a really great manufacturing.

I did polished my M&P9 internals, but I didn't want to play with plunger and used APEX whole set.
Your work looks $160 less expensive

I wish that were so!!! What I did doesn't change pre-travel, over travel or reset. All it does change the feel of the trigger. It hits the wall at the same point and breaks at the same point.


In regards to the plunger, if the overall height doesn't change and the top remains flat then it'll function the same. Cut the height down and the striker may not release properly.

 

[Ruger Nut]

Everyone's favorite topic. Its well established what the flaws are and how to correct them. But there's more to it than throwing a new trigger. Here's what I did.

1. Smoothed the trigger bar surface where it interfaces with the striker plunger
2. Smoothed the striker plunger hole
3. Smoothed the sear actuator
4. Smoothed the trigger bar side against the frame.

By 'smooth' I mean removing the absolute minimum amount material by sanding with progressive grits then polishing. For sanding I use finger nails files unless I need something very course then its regular paper. Black, white, pink, blue nail files/buffers. For polish I use Simichrome but any of the known products work..Flitz, Mothers aluminum polish.

3 pics of the trigger bar:
Pic 1 shows the factory finish. Its not overly smooth
Pic 2 shows the bar after a few passes with 180 grit paper. Its now very easy to see the uneven surface
Pic 3 is polished up. I didn't smooth it completely flat as I didn't want to remove too much material

2 pics of the plunger hole:
Pic 1 I wrapped machine screw with 2000 grit paper and made a few passes with the drill set at moderate speed
Pic 2 is after

Which M&P is it?
What were the trigger pull weight before and after?
I have several LE Trade in 1.0 M&P 40's. What I did to them was, polish the safety plunger bore, install a 6lb. trigger spring, an APEX trigger, polish all the moving parts of the trigger bar, reduced spring in the safety plunger, and polished the safety plunger.
Before, trigger pull weights were 5.7 lbs.-5.4 lbs. Afterwards, the trigger pull weights are 4.5 lbs.-4.7 lbs.
My 2.0 M&P Compact .40's trigger is one of the BEST S&W has ever made. I left it alone (5.0 lbs. from the factory).

 

[Jim2527]

It's an 9mm M2.0 5" Performance Center. I don't recall the initial trigger pull but it was nothing special. After all the work it was in low 2lb range with a competition sear spring which I didn't like. That spring was swapped backed to OE spring.

There's an Apex forward set sear actuator inside.

 

[ChillyDog]

I've polished the same parts you have including the feed ramp. The trigger always smooths out. Nice what a little elbow grease and some time does.

 

[rjroberts]

Similar to Chilly Dog. My M&P 45 2.0 trigger was "gritty". I looked at the trigger bar, the plunger ramp, and it looked like it had "metal splatter" (for lack of a better description). Smoothed it, and it was a completely different pull. I'll confess to being too lazy to do the plunger hole, but the trigger is fine as it is, as far as I'm concerned.

To horrify purists. The tool I used was on a Leatherman Wave. The file tool (no, don't panic) has a file on one side and a diamond dust polisher on the other. Didn't come out as shiny as Jim2527's work, but smooth nevertheless.

 

[STORMINORMAN]

It's amazing what a Q-tip and some Mother's can do...

Cheers!

 

[dla]

Nice to see somebody posting about solving a problem. Great job!

 

[JGKC9AYC]

Do you guys use Flitz polish or paste, or is there a difference?

 

[Jim2527]

Do you guys use Flitz polish or paste, or is there a difference?

At the 'polishing' stage it doesn't make a difference. Flitz, Simichrome, Mothers….

When doing projects like this remember the grit rule of thumb…always double your grit. If you start with 100 the next should be 200 then 400 then 800 etc. Anything more than double won't remove the marks from the previous grit.

 

[Ruger Nut]

Do you guys use Flitz polish or paste, or is there a difference?

I bought a tube of it about 20 years ago. There is other products that do the same job, or better, on the market.

 

[CBStuard]

I do similar. For sanding I got a bunch of wood popsicle sticks from Hobby Lobby or Michaels and a roll of double side tape. Not the thick stuff, this;
Scotch Removable Double-coated Tape, 3/4 in. x 400 in. - Walmart.com
I cut strips of the wet/dry paper and stick them on the stick. BTW a trick w/ wet/dry paper is, if you use water or oil on it, that makes it work like the next step finer grit.