DA breaking after SA... What do ya'll think?

[Scarlett Pistol]

My buddy picked up an SP-01 manual safety. The guy had put a bunch of Cajun greatness into it and kept is as a back up pistol for 3 gun so it is barely used. When I broke it down for some checking and other touch ups the parts don't look to be polished or anything. He just installed them.

The interesting thing, which I haven't seen in my limited exposure, is that the DA breaks after the SA. So he has a 85 trigger with the set screw for over travel and he has to set the screw for the DA because it breaks further back than the SA. Does that make sense?

I have my ideas on what to do in order to shift the DA break forward, but I wanted to hear what ya'll think first.

PS - I do not think it is caused by the Cajun parts, specifically the disconnector that is in there. I can test that by throwing an OEM disconnector in there and seeing what happens (which I will do when I break into this for the fixing) - it's just not my first, second, or third idea as to why this would be happening due the the QA and tolerance quality they hold. But I still will check.

[Tok36]

So the goal is to advance the DA without advancing the SA so that the SA over-travle can be reduced by the over-travle set scerw.

I am thinking that removing some material from the underside of the disco wings would achieve this.

[adrian]

     Hiya Scarlett Pistol and thx for the thread. If I understood your post,besides the technical aspects. It almost sounded like your mate bought a gun, put some tuned up parts in it to use as a back up.Great idea many shooters  wish they did mid stage when a firing pin,trigger spring,or slide stop break. Maybe your mate set up the gun to function like he wants it to run,which is what I'd expect of the folks I've met who shoot 3 gun. So please run your intended project over with him, from what I've heard once ya shaved off some material,its kinda a chore to try and return it. Cheers. Be well.

[Scarlett Pistol]

So the goal is to advance the DA without advancing the SA so that the SA over-travle can be reduced by the over-travle set scerw.

I am thinking that removing some material from the underside of the disco wings would achieve this.

That?s what I was thinking. Removing a little material from the underside and bevelig that edge. Glad to see I have initial consensus.

     Hiya Scarlett Pistol and thx for the thread. If I understood your post,besides the technical aspects. It almost sounded like your mate bought a gun, put some tuned up parts in it to use as a back up.Great idea many shooters  wish they did mid stage when a firing pin,trigger spring,or slide stop break. Maybe your mate set up the gun to function like he wants it to run,which is what I'd expect of the folks I've met who shoot 3 gun. So please run your intended project over with him, from what I've heard once ya shaved off some material,its kinda a chore to try and return it. Cheers. Be well.

Just about. My buddy bought from a guy who had done that already. I?ve run the project by my buddy and he approves.

[Stuart]

what sear number in the gun? or did the sear get replaced? also number on the ejector housing? either need to move the SA release back, sound like there is room. or as you guys are thinking, move the DA forward, but be mindful of how short you will make the DA stroke. if too short it will feel funky.

[Tok36]

I think that Stuart made a number of interesting points here. A number of which touch on areas of the CZ timing that i am grey on.  If i am reading things correctly, the different numbered sears are adjustments to the sears lower leg, while the different numbers on the ejector/sear cage are adjustments to the depth of the pad on the bottem which effects when the trigger bar is lowered in the DA cycle. If this is incorrect i am interested to hear the the differences in the numbered parts.

Other than adjusting the part of the trigger bar that picks up the lower leg of the sear or the sear leg its self, how would one move the SA break rearward?

The part about moving the DA too far forward makes sense. I have an 85 Combat that i am working on that may have this issue and the increased DA over-travle from the DA breaking early feels really unpleasant.

[MoRivera]

I've found that sometimes a new disconnector needs fitting on the underside of the 'wing/lug'.  What is happening is that in double-action, the disconnector is not letting the trigger bar pass underneath out of the way early enough and can sometimes even be pulled all the way back (no set screw) without the hammer falling, whereas the SA break is just the sear on the hammer, with the trigger bar already clear of the disconnector.


Notice how the trigger bar quickly passes underneath the disconnector's lug at rear-most DA trigger pull, which releases the hammer:
 



And then in SA, the trigger bar is already past that lug so the trigger pull is only working on the sear:


 
What Stuart is referring to here....

what sear number in the gun? or did the sear get replaced? also number on the ejector housing? either need to move the SA release back, sound like there is room. or as you guys are thinking, move the DA forward, but be mindful of how short you will make the DA stroke. if too short it will feel funky.

...is if you take too much material off the lug, it makes the trigger bar pass underneath the diconnector too soon during the DA pull, so a) The hammer doesn't get enough rearward cocking and could lead to light strikes depending on hammer spring, and b) since the hammer breaks early, the trigger slams back to the rear the rest of the way with almost no resistance...so it kind of feels like when you miss a step on the stairs and you come down hard and awkwardly.

How much material to hone away can depend on the particular gun.  Go very slow and check each time, for me just removing 0.05" was enough on a few guns.  At a certain point you can get the DA and SA break to be in the same place and set you over travel screw accordingly.

[Ruber]

Have you test fired the gun much?  I?d run a bunch of rounds through it DA with the hammer spring you want to use to test for reliable ignition.  If they dropped in a reach reduction kit and left hammer/sear factory, the DA stroke might be as short as it can get reliably already.