S-120 Trigger return spring

[68Firebird]

I know some here have reported replacing springs on their Canik/TriStar pistols. Having read good reports on M-Carbo springs I ordered the complete CZ-75 set, along with the floating trigger pin, for my S-120. While I had it open to install the springs I also did some polishing on the trigger and trigger bar. Upon reassembly I found the trigger would not reset reliably while dry firing. It reset about 70-80% of the time. I contacted M-Carbo, not as a complaint but as a heads-up. Their response was that maybe the S-120 just needs the stronger trigger return spring. Fair enough.

Out of curiosity I decided to order a TRS from Cajun Gun Works. I installed that one today and the trigger still didn't reset reliably in dry fire.  (I haven't had an opportunity to shoot the gun since I started this project.)

I reinstalled the OEM TRS, leaving all the rest of the M-Carbo springs I had installed in place.  It now resets every time.

This is not a complaint or criticism of either M-Carbo or CGW, I just wanted to share my experience with the TriStar. YMMV

As an aside, I also replaced the trigger spring and main spring on my S&W 642 with M-Carbo parts and it made a nice improvement in the trigger pull. I haven't tested it yet for light strikes but I don't anticipate a problem there.

The positive side of all of this is I know have a much better knowledge of the guts of CZ style pistols!

[Rmach]

Your trigger bar spring is out of adjustment causing the trigger bar to bind slightly.  The factory trigger return spring is strong enough to overcome this, but not the lighter CGW or Macarbo return spring.  Here's a good read on how to adjust the trigger bar spring:

https://forums.brianenos.com/topic/232956-trigger-bar-support-spring-tuning/

This will most likely solve your problem. and it will only take a minute to do.

[68Firebird]

Thanks for the tip, Rmach!

I didn't get much clarity from that thread, but I'll do some more research. Since it appears to be held in place by just one central screw, how do you adjust it?

[68Firebird]

I found this description of adjusting the spring.  Looks like you just force it up or down a bit.
https://drive.google.com/file/d/1BN90-AH5j8uMI2_AYP0XeZKnsi0JSdhl/view

[Rmach]

One of my 75s had the same problem you have with the lighter spring, and I followed this advice and it worked perfectly for me:

When looking from the rear of the gun. The right side should come about 1/8" above the bottom of the trigger bar when you pull the spring out of the groove to the inside. The left side should just lightly touch the trigger bar.

Make sure both ride in the groove on the bottom of the trigger bar.

My right side was about a 1/4" above the bottom of the trigger bar, and I just pushed/bent it down with my finger till it was an 1/8".  The left side was fine. This gave me a perfect trigger return with the light spring.

[68Firebird]

Yep! That's just what the other link I found indicated. Sounds simple enough.

Thanks for your help.