SAO conversion problems

[Mists.Fire]

I installed a flat SAO trigger and removed my disconnector. The set screws are backed out completely. The trigger isn’t engaging the sear intermittently. If I lift fpb lifter and cock the hammer the trigger will work once. If I cook the hammer again it will not engage the sear again. Please help.

[Tok36]

I assume that you are talking about a CZ97B. If this is correct i would check your Trigger Bar Spring. The TBS should be pushing up on the trigger bar on both sides. The spring ends should be positioned in the grooves located on the underside of the sides of the trigger bar.

[Mists.Fire]

I appreciate the response, but the trigger bar spring is resting in the cradle of the trigger bar.

[M1A4ME]

You say the sear won't release the hammer?  Or the sear won't stop/hold the hammer in the full cock position when the slide moves forward?  Or the hammer falls but the pistol doesn't fire?

I converted a CZ75 Compact to SAO a couple years ago and had an issue with the firing pin block not resetting.  Racking the slide would cock the hammer.  Pulling the trigger would release the hammer.  The gun would not fire.

The trigger has to move forward far enough to get the sear and the firing pin block to reset.

You mention messing with the firing pin block lifting arm so it made me wonder.

Here's a picture of mine.  The area on the front of the trigger (it's up inside the frame where you can't see it) was hitting the frame and not letting the trigger move forward far enough to allow the firing pin lifting arm to drop down into it's correct place behind the trigger bar.

I ground off just a small amount (you can't even see it when the trigger is installed in the frame) and it worked.  That also allowed the screw that adjusts for forward movement to actually have an adjustable range and work as intended.  Not saying it's your issue, just something to look at.  If your trigger's screw is backed out and you're still having reset issues you might look at this.  It won't take much metal removal to check it and the screw will still be able to adjust it if that is the issue.  Good luck with it.

[ddugh56]

My LGS has a BD for $670.00. If I did not already have a 'B' I'd be taking that beauty home.

[schmeky]

Not sure of the build specifics, but if you are "only" installing a SAO trigger and not modifying the SA reset, this is most likely your issue.

CZ, SAO triggers are designed to be used in pistols with a short SA reset.  We have seen some CZ's that will not reset when an SAO trigger "only" is dropped in.  Not enough adjustment to attain a reset.

SAO trigger by itself does not improve anything, it merely deletes the DA.  We tell folks if you are going SAO, you need to build the pistol around the SAO trigger. 

[dohc97]

Not sure of the build specifics, but if you are "only" installing a SAO trigger and not modifying the SA reset, this is most likely your issue.

CZ, SAO triggers are designed to be used in pistols with a short SA reset.  We have seen some CZ's that will not reset when an SAO trigger "only" is dropped in.  Not enough adjustment to attain a reset.

SAO trigger by itself does not improve anything, it merely deletes the DA.  We tell folks if you are going SAO, you need to build the pistol around the SAO trigger.

I am about to order the SAO trigger for my 97B. Can you confirm that it will work with my 97B? I have the SAO trigger in my car right now. Do I have to order other parts?

[Dan Wesson]

No problem... yet... I just removed the FPB and spring and did a function test and range trip.  SAO does work with the stock 97b trigger.

I ordered a 5SAO aluminum (CZ factory part) trigger from CGW and a sear spacer.  I'll switch out the triggers and remove the FPB-lifter & spring, replacing with the spacer later this week.  So far so good.  I'm looking forward to getting rid of the long pre-travel.  Adjusting the "over-travel" a bit if needed is a bonus.  I just want to keep a proper reset.

Already polished the internals and installed a CGW floating trigger pin previously.

Appreciate the posts so far.  I'll be back to update and report if I run into any problems.

[Dan Wesson]

Finished the upgrade today. It was an easy install:
Removed the FPB lifter arm and spring and replaced it with the CGW sear spacer.
Switched out the stock DA/SA trigger for the CZ 5SAO trigger, adjusted the take up but still allowed a good reset, adjusted the over-travel but had to back the screw out a quarter turn so the sear did not drag on the hammer hooks.

I am pleased with the result. Reduced take up by 1/2” or so and the over-travel is 1/16-1/8” past the wall. Very nice reset.

I’m going to put a few hundred rounds down range and dry fire some more. I may (or may not!) lower the hammer hooks to reduce creep but it’s not much of a problem at this point— the pull is very smooth.






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[Dan Wesson]

After a bit more dry fire, I noticed that the bottom of the sear was dragging on the hammer hooks.  I simply backed out the over-travel screw 1/4 turn-- fixed!

I think using Vibra-Tite VC-3 on the adjustment screw threads is going to work quite well.  They will turn if needed but remain locked in place after adjustment.

[Dan Wesson]

Finally got the converted CZ97b to the range this morning. Results follow...
7yds, 2hand grip, unsupported:


10 yds, 2 hand grip, unsupported:

[dohc97]

Finished the upgrade today. It was an easy install:
Removed the FPB lifter arm and spring and replaced it with the CGW sear spacer.
Switched out the stock DA/SA trigger for the CZ 5SAO trigger, adjusted the take up but still allowed a good reset, adjusted the over-travel but had to back the screw out a quarter turn so the sear did not drag on the hammer hooks.

I am pleased with the result. Reduced take up by 1/2” or so and the over-travel is 1/16-1/8” past the wall. Very nice reset.

I’m going to put a few hundred rounds down range and dry fire some more. I may (or may not!) lower the hammer hooks to reduce creep but it’s not much of a problem at this point— the pull is very smooth.






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So, to convert a 97B to SAO, these are the parts needed?

https://cajungunworks.com/product/s-spacer-sear-spacer/
https://cajungunworks.com/product/5sao-single-action-aluminum-trigger/

[Dan Wesson]

Finished the upgrade today. It was an easy install:
Removed the FPB lifter arm and spring and replaced it with the CGW sear spacer.
Switched out the stock DA/SA trigger for the CZ 5SAO trigger, adjusted the take up but still allowed a good reset, adjusted the over-travel but had to back the screw out a quarter turn so the sear did not drag on the hammer hooks.

I am pleased with the result. Reduced take up by 1/2” or so and the over-travel is 1/16-1/8” past the wall. Very nice reset.

I’m going to put a few hundred rounds down range and dry fire some more. I may (or may not!) lower the hammer hooks to reduce creep but it’s not much of a problem at this point— the pull is very smooth.






Sent from my iPhone using Tapatalk

So, to convert a 97B to SAO, these are the parts needed?

https://cajungunworks.com/product/s-spacer-sear-spacer/
https://cajungunworks.com/product/5sao-single-action-aluminum-trigger/

Yes... but in addition I would strongly advise installing the Floating Trigger Pin in place of the stock roll pin (which has to be removed anyway to switch triggers).  https://cajungunworks.com/product/floating-trigger-pin/
Function is better (smoother action) and it is much easier to install. I would go so far as to say you must use it with the SAO trigger to fully realize its benefits.
I had previously installed the FTP in my 97b.

[dohc97]

Almost ready to order the needed parts; sao trigger, FTP, and sear spacer. What about schmeky's response about a short reset? Is there any part I have to order to get a short reset?

[Tok36]

Almost ready to order the needed parts; sao trigger, FTP, and sear spacer. What about schmeky's response about a short reset? Is there any part I have to order to get a short reset?

You mentioned a Sear Spacer. This spacer is used when removing the Firing Pin Block. Removing the FPB reduces the Single Action reset distance. This will eliminate the potential issue that schmeky is talking about.

If you have not already done so i would add a replacement Firing Pin Retaining Pin. You will need to drive out the factory Firing Pin Retaining Pin when you remove the Firing Pin Block Plunger and FPBP spring from the slide. The factory pin is a weak part that is prone to break.

61100 Firing Pin Retaining Pin
https://cajungunworks.com/product/61100-tempered-spring-steel-firing-pin-retaining-pin/