I have a thread in the S&W forum but not getting much attention.



What is the middle spring?  I put my FSS in and have that spring left over.  I installed a RAM also.  Could not install the larger sear spring I believe that is the spring on the right.  I will have to get a different sear block.

Is that the firing pin block spring?

I read last night, that there are two springs included and to use the one that fits your pistol. Must have been difference in S&W pistolas.

Danny

two springs included for what?

I dont think so, the spring I used for the Striker Block was similar to the OEM spring

Those look like sear springs. How did you install the FSS if you missed the the sear spring? Apex says the FSS requires the 1/8" inch sear spring which means you need the new block or get the current one modified. Also, you're installing a RAM and a FSS? You know Apex recommends the FSS only be installed on thumb safety models because of the extremely short pre travel.  And AFAIK the RAM for thumb safety models is not ready yet.

I hope this is not a HD or carry gun you're messing with, because it sounds like you're doing unsafe and incomplete mods.

No I dont have a thumb safety,  as I said I have to get the other Sear Block.  Link me to where Apex says to only use it in a thumb safety version? ETA the Randy Lee FSS install video, Randy is installing the FSS into a non thumb safety version.

He just told you for what. Your gun uses the one on the right, so you don't need the one in the middle. There must have been a change in springs at some point from the factory but they include both versions.

Copy?

What these two said. I just installed one right after Christmas.








 

negative neither spring fits in the sear hole and Apex says to use the larger 1/8th sear spring  ( From Apex's website ––-This kit is recommended for COMPETITION USE ONLY and REQUIRES the use of the larger 1/8 inch sear spring & plunger set up**)

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.

This explains it.   Found this in a PDF

ETA this link shows a pic of the original FSS kit with out the additional lighter weight RAM spring included
http://www.apextactical.com/blog/wp-content/uploads/FSS_Kit_800.jpg
This link shows what the current kit ships with

https://apextactical.com/store/avactis-images/FSS-Trigger-kit-web-600x400.jpg

I've only ever seen the FSS recommended with the thumb safety for duty use on another forum we can't mention. I guess if it's for competition, then a lack of a thumb safety shouldn't be a problem.

Be careful when ordering a new a sear housing block. In my research on the M&P there have been a few variants and the switchover dates haven't been established. When you order it, make sure it's the sear block with the larger sear spring and plunger, and it's a replacement for non-thumb safety models. You don't want your new RAM to be useless.

Last I heard, S&W was gonna simplify their parts count and just use the thumb safety ready sear block in all models. The only difference will be if the block has the TS internals or not. In fact, S&W has already started making non-TS models with TS ready parts. The VTAC and I believe the carry kit M&Ps have frames with plugged TS cutouts and TS sear blocks.

Thanks for the heads up, I do have a source for the correct Sear Block.