CZ Tactical Sport Trigger?

Discussion in 'Centerfire Pistols & Revolvers' started by LDBennett, Mar 10, 2020.

  1. LDBennett

    LDBennett Well-Known Member

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    My CZ TS has a sub 2 pound trigger that can be a be hard to use as it is easily set off by an errant finger. If the shooter does his part then it is great. But with so many different pistol that I shoot, this gun’s trigger is hard for me to learn and remember. It has two stages: a short light take-up (before the trigger linkages move the sear) and a crisp very light pull as the sear moves off its hammer engagement shelf.

    I would like a larger change in pull level between the take-up and the actual pull. That is, I want to increase the pull stage and not the take-up stage. The answer is to increase the hammer spring a bit to maybe add about a 1/2 pound increase in the pull level.

    The problem is: what spring do I change to? I get conflicting info on what is in the gun. Has anyone done this hammer spring change to add 1/2 pound or so to the CZ TS trigger pull level? If so, what hammer spring did you you use and from whom? I see Wolf makes a spring set for the CZ 75. But I have no idea how those springs compare to what comes in the the CZ TS from the factory.

    LDBennett
     
  2. bamajoey

    bamajoey Well-Known Member

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    Have you checked with Cajun Gun Works? Give them a call, great folks to work with.
     

  3. LDBennett

    LDBennett Well-Known Member

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    Their stock answer was to replace the hammer and the sear. That's a bit much for a trigger that is already less than 2 pounds and has minimal creep. Creep is safety because creep is a measure of sear engagement in the hammer. Some is not bad if it is smooth. So that is out. They did not reveal exactly what hammer spring is in the gun.

    I did find out the color code for CZ 75 hammer springs though. Maybe I can determine what is in the gun by the color. So I order a spring set from Wolff Springs that includes 16, 17, 18, 19. I did determine that the regular CZ75B has a 18 to 20 pound spring. But my CZ TS surely does not have a stock CZ75B spring in it. I think it might be the 16# spring (??). If nothing else once I get the 4-pak from Wolff I can calculate the CZ TS stock spring constant and go with math to know where to start. But there is always the install and test method.

    All I want is about a 1/2 pound increase in the trigger pull to get more delineation between the take-up and the actual trigger moving the sear.

    LDBennett

    Note: It appears that the color of the spring denotes the strength, according to a internet YouTube video (??):
    Blue 13#
    Black 11.5#
    White 8.5#
    Also in a CZ75B hammer spring weights below 15# requires recoil and firing pin spring changes and ammo changes for perfect reliability.
     
  4. LDBennett

    LDBennett Well-Known Member

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    Well....it didn't work! The CZ TS hammer spring was not color coded. I got the Wolff spring set (16#, 17#, 18#, 19#) and measured/calculated them all and the CZ TS hammer spring. All but one had an actual force on the hammer less than the CZ TS spring based on calculated values. The exception was the 19# spring which calculated to be about 20% stronger. Once installed the trigger pull remained at about 1 3/4 pounds, below my goal of 2 1/2 pounds. So I give up with this approach.

    I know if I increase the spring force on the sear then the trigger pull will go up but on both stages of the pull. Add to that having to remove the trigger module and disassembling it to do anything with the sear spring is a pain (the trick is a slave pin used during reassembly).

    The trigger is sweet as is and I guess I'll just have to learn how to use it to avoid accidental trigger pulls. Such is life!

    LDBennett
     
  5. LDBennett

    LDBennett Well-Known Member

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    I did more research as to how CZ got the TS trigger pull to less that 2 pounds.

    I have done trigger jobs on many of my rifles and handguns. It is common to change the sear and hammer springs to reduce the pull. I have polished sear/hammer engagement surfaces but only rarely did I change their engagement angles. All those changes have impacted the trigger pull. But CZ did it a bit differently, it appears.

    The standard CZ75B and the Tactical Sport share the same 20# hammer and sear springs. CZ changed the sear/hammer engagement angles in the case of the TS, it appears. That reduces hammer cam back (trigger pull is working against the hammer spring directly rather than the sear just working against the friction of sliding the sear on its hammer engagement surface). Getting the angles just right is a slippery slope because if you get the angles wrong then the sear will have a propensity to slide off the hammer engagement surface with a minor bump. CZ has added a very tiny bit of creep which is the depth of the sear/hammer engagement to regain a bit of safety. CZ did a good job IF the shooter learns the trigger and only touches it at the last moment before the firing of the gun. The shooter of the TS has to learn finesse in his/her trigger pull to match the light trigger of the TS. Note that some competition contests have rules regarding minimum trigger pulls and less than 2 pounds has to be considered too light for some competitions. The CZ Shadow II has a 3 pound trigger pull for that very reason. Apparently the competition for which the TS was designed (??) has no such limitation (?).

    LDBennett
     
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  6. LDBennett

    LDBennett Well-Known Member

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    Finally decided that less take-up would make the trigger more manageable (Note: the trigger is great out of the box at about #2 but I didn't like the longer take-up because it didn't allow you to repeatably stage the trigger as the transition from trigger take-up to sear movement was easy to miss in the pull). Other ideas did not work out for me.

    The CZ TS has trigger adjustment for take-up and over travel.The goal is to reduce the take-up. First you have to remove the slide and then back out the over travel screw using a 1.5mm Allen wrench, until it is flush with the back of the trigger face. Then pulling the trigger all the way, the take-up adjustment 1.5mm Allen screw is revealed on the top of the trigger inside the receiver (It is down inside the trigger). Screw the adjuster in to reduce the take-up but do not remove it all or the hammer and sear may loose any safe engagement and the gun will fire with any small bump. Once you have the take-up adjustment correct then adjust the over travel screw. Don't over adjust this screw or the trigger will not reliably reset. Find the exact point where that occurs and back the over travel screw out at least a half turn.

    Now my trigger us such that a gentle squeeze sets the gun off with virtually no take-up and minimal creep. I don't try to stage the trigger because I removed virtually all of the take-up (a tiny amount was left to assure a safe bump proof trigger).

    A range test is next but the trigger feels much more manageable and sub #2 pull.

    LDBennett
     
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  7. drymag

    drymag Well-Known Member

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    I recall you as not having any use for a bump stock and it would be protected from a drop firing. But, being light on the sear hook, how does the wear still prevent those happenings?
     
  8. LDBennett

    LDBennett Well-Known Member

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    drymag:
    I am not sure exactly what you are asking but:
    A "correct" take-up adjustment is to not remove any sear/hammer engagement and only mostly remove the take-up in the trigger movement.

    Take-up is the motion of the trigger without any movement of the sear.

    Creep is the sear sliding across the sear/hammer engagement surfaces. The CZ TS sear/hammer engagement geometry is such that the engagement is minimal but there is still a safe amount and I did not change that.

    Over travel is the motion of the trigger after the hammer drops. But there must be enough so that the trigger can reset which means the trigger can re-engage the sear.

    Hope that helps. I just wanted to complete this issue as I kind of left it up in the air. Changing these adjustments can make the gun unsafe or disable it. So those not inclined to do any gunsmithing work probably should not make ether of these adjustments and just run the gun with the factory adjustments (they apparently vary from gun to gun as my son-in-law found out with his identical CZ TS).

    LDBennett