Below you will find the instructions for installing the Apex Forward Set Sear and trigger.

You can download the PDF here:
Apex_FSS_Letter V2

The installation video is also available on Youtube at the following link:
Apex FSS Install

What you are looking at is our new forward set sear and trigger kit. I wanted to share some technical information about the parts and their interaction. First and most importantly the kit will provide a substantially shorter overall trigger travel than the stock M&P or our DCAEK.

The take up and over travel limits are defined by the trigger body. I wanted to ensure that no stresses were placed on the trigger bar/trigger connecting pin or trigger safety pin. I have seen several of both walk out on factory stock triggers and do not want this to occur in my design. The trigger uses the factory trigger bar and connecting pin from the original pistol that the kit is being integrated in to. We recommend that the pin be inserted into the trigger body from the left side, using a drop of oil on the hole to prevent binding or galling. We should have the install video up by the time you receive this package. The Aluminum trigger and safety lever are hard anodized black, so the hard durable shell is about .002″ in depth rather than the .0005″ depth of standard color anodizing. It should provide excellent service life.

The striker block plunger has been redesigned. Because we moved the trigger break point forward, we needed to ensure the striker block plunger cleared the channel as soon as possible. A domed or rounded factory striker block plunger or our current USB will most likely result in failures to fire and damage to both plunger and striker.

The sear has greater mechanical leverage than any of the sears currently manufactured (factory MIM, Pro sear, Tactical sear as well as our standard hard sear). The combination of springs should yield the following results:
• Factory TRS and sear spring- 3.0 lbs
• Competition spring kit- 2 lbs (or less)
• Springs included in kit- 4.0-4.25 lbs

The included sear spring is substantially stronger and has six coils. Due to the extremely short trigger travel, we STRONGLY recommend that you use a sear block with the current factory production .125” diameter sear spring/plunger, or have your sear block milled to accept the latest version.

Also included in the kit is a lighter weight RAM spring. Because the trigger break and trigger/sear reset point are closer together, the system can be more sensitive to sear flutter. Our standard weight RAM spring can increase the chances of the trigger bar popping back under the sear cam if the trigger loop is excessively worn.

We’re also now including a trigger bar pivot pin, pre installed into your trigger. When you remove the pin from the factory trigger, set the factory pin aside along with the trigger and use the FSS and the pre installed pin to attach the trigger bar.
Final notes: We left the trigger face square to encourage the shooter to articulate the trigger straight to the rear. A random group of test shooters in classes and in competition seemed to like the feel. We are also pursuing making a plastic version with rounded contours.

This is an evolutionary process so please let us know what you think.

Randy Lee

scott / September 9, 2011 / Random Apex


  1. jJerry Bridges - February 26, 2012 @ 4:46 pm

    Hi, I installed the trigger and sear set, and all worked well. The reset was so soft, I ordered a RAM and installed it and the trigger would barely release the striker. Took it apart and did it all again and the same result. Took the RAM out and the trigger is fine.


  2. Kevin - December 5, 2015 @ 11:08 am

    Just thought I would drop you a line for future reference if anyone asks about the APEX FSS and Aluminum trigger kit. I just installed it on a new 2015 M&P 9mm and took it to the range. What an awesome trigger. My concerns of it being too light for someone new to shooting were totally put to rest. In my opinion this trigger & FSS make the M&P a more suitable handgun for someone new than the M&P with the stock trigger. The travel on the center safety and minimal pre travel are more than enough before the trigger breaks. And when it breaks it breaks clean with no extra effort. I would recommend the FSS and Aluminum trigger for anyone who owns a M&P.

    The install was straight forward and completed within an hour and a half. Going slowly to ensure nothing was missed. The only issue is then pin on the aluminum trigger. Nothing short of a small 2.5 inch vice would budge it.

  3. Kurt - May 5, 2016 @ 12:03 pm

    Like butter. Takes the worse trigger I’ve ever had and places it in the Kimber 1911 catagory. I’ve done four of these kits so far. Exceeds all expectations. Well done Apex!

  4. paul - May 6, 2016 @ 8:32 am


  5. Rodger Smith - January 9, 2018 @ 1:18 pm

    I installed a DCAEK it comes with all the enhancements from Apex except for trigger.. I just ordered the polymer trigger it came with a another sear spring purple. I was under the impression that since I had the Sear Springs from the enhancement kit why did I have to add the sear spring that comes with the trigger. Because I like my trigger with sear spring that came with the DCAEK.

  6. paul - January 11, 2018 @ 1:42 pm

    You do not need to change the spring.

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