CZ Tuning 101 with Professor Atlas

[ArrDave]

And ?

It's due out in march, uses two dual coil springs instead of one whateveryoucallit style spring they currently use. The springs individually are rated at over 250,000 cycles, and even were one to fail, there's another one that will keep it operational. He's really excited about it. He said it's going to be really reasonably priced as well.

Thanks! The cycle life is exciting.

The busted spring thing seems like it would be only for a self defense application where more trigger weight than needed is ok, but maybe I am missing something.

well self defense thing or not having to manually reset your trigger should it break mid-stage as well.

[IHAVEGAS]

And ?

It's due out in march, uses two dual coil springs instead of one whateveryoucallit style spring they currently use. The springs individually are rated at over 250,000 cycles, and even were one to fail, there's another one that will keep it operational. He's really excited about it. He said it's going to be really reasonably priced as well.

Thanks! The cycle life is exciting.

The busted spring thing seems like it would be only for a self defense application where more trigger weight than needed is ok, but maybe I am missing something.

well self defense thing or not having to manually reset your trigger should it break mid-stage as well.

Time will tell. I don't think that most competition shooters would be willing to run a 2x heavier than needed trigger return spring 99+% of the time.

[mrgrabow]

that single action looks short for a SP-01.. nice I couldn't get mine that far back.. damn good job.

I actually took a little off the sear, off the 'foot' of the FPB lifter and the trigger bar where it picks up the lifter to get it that short.

On my SP 01 I machined the ledge on the firing pin that catches the FPB down to .018 thick so that the FPB needs less travel to clear it, then shortened the foot on the lifter to remove the excess travel. Makes the reset pretty sweet.

Czhase, by chance do you have a photo or illustration of where exactly you machined the ledge? And when you refer to the "foot" of the fpb lever, are you referring to the part which interacts with the trigger bar or the part of the lever which interacts with the block itself (the part residing in the slide)?

Edited January 15, 2016 by mrgrabow

[shooterDrew]

Just used this thread to help me work thru a polish job and installing CGW internals on a new CZ75 compact ... THANK YOU! Great resource!

Sent from my iPhone using Tapatalk

[eerw]

Sight pushers don't seem to work well with CZs, I use a brass punch and a sturdy vice. Putting the slide in the freezer helps too.

our pusher works pretty well on most of the pistol sights in CZ lineup.

TS is better done with hammer and punch.

[tmay]

One thing I didn't see mentioned in this thread is adjusting the trigger bar spring (the spring that pushes up on the underside of the trigger bar). I did the work in this thread, and ended up with a false reset that would drop the hammer in single action without moving the firing pin block to let the firing pin move. I noticed this while hand fitting the short reset disconnector.

After talking with David at Cajun gun works the solution was to adjust the spring so that it rides in the indentations in the bottom of the trigger bar. The left side needs to just touch the trigger bar, the right side should be 1/8 to 3/16 above the bottom of the trigger bar. This fixed the false reset.

I had not touched the spring while doing the work, since I did not put in an extended mag release.

Looking at my xmas present (CZ 75 compact), it appears that at the factory they installed the spring with both sides even in height (eyeballed this, did not measure) and the spring spread such that both sides made firm contact with the frame rather than rode the center of the trigger bar grooves naturally. The gun seemed to work fine, given that it was completely stock.

It would be nice to know more about the effects of getting this thing adjusted correctly, and what kind of problems you get into when it is wrong. Maybe this is not such a big deal since you do not seem to find much written about it ?

If this is adjusted incorrectly it will not hurt anything with the gun stock.

If you work over the trigger in a fpb gun you can get a "false reset". This is where the trigger bar catches and resets in front of the sear but hasn't come far enough forward to catch the firing pin block lifter arm. Sometimes you can feel a light click (reset) when the trigger bar catches the sear. If you pull the trigger from this point the hammer will fall and hit the firing pin. The problem is that the firing pin block is still engaged. This causes the firing pin to slam into the firing pin block. This will beat up both parts. It will also cause failure to fire if shooting from reset.

I don't think most people realize that their gun is doing it since they let the trigger out past the reset point. I've felt a couple of guns that were experiencing this issue and the owners were unaware of it. I knew to look for it because a friend of mine had his gun go down due to this. I had it on one of my guns and noticed it while fitting the disconnector. David at CGW walked me through the adjustment. My second gun I used a drop in disconnector and adjusted the spring when I was doing the trigger work.

First...my personal thanks to everyone who contributed to this thread...much appreciated and very educational.

I just finished doing over my SP-01 fpb manual safety variety. Only parts I added were a CZC Comp hammer, an 85 trigger with the over travel screw and a 13 lb hammer spring. VERY pleased with the improvements in SA and DA pull weights. SA is a smooth 3.5 lbs break with just a noticeable increase in weight when the FPB lever starts to rise...I didn't polish any of those parts yet.

While filing down the safety/sear to get the safety to engage in SA with the new Comp hammer, I accidentally discovered that I have this false reset condition described above. I discovered I had two reset points but didn't realize that the FPB wasn't disengaging at the first reset point....so I have slammed my FP into the block a few times. I was about to post a thread asking if these two reset points could be timed together by some disco adjustment when I found this information above which I believe describes my situation exactly.

Am I reading this correctly that this can be overcome by adjusting the trigger bar spring to different heights on the left and right side? I did remove this and the mag release spring when I disassembled the gun as I was contemplating getting the frame refinished but decided to reassemble the gun for practice before I forgot how to put it back together. I was not aware of a difference in the two sides of this spring when I took it out....sound like it might not make any difference in a stock gun but I am scratching my head trying to understand how unequal spring pressure pushing up on the two opposite sides of the trigger bar is a good thing.....am I missing something in my analysis?

Thanks in advance for any assistance with this one....

[bthoefer]

One thing I didn't see mentioned in this thread is adjusting the trigger bar spring (the spring that pushes up on the underside of the trigger bar). I did the work in this thread, and ended up with a false reset that would drop the hammer in single action without moving the firing pin block to let the firing pin move. I noticed this while hand fitting the short reset disconnector.

After talking with David at Cajun gun works the solution was to adjust the spring so that it rides in the indentations in the bottom of the trigger bar. The left side needs to just touch the trigger bar, the right side should be 1/8 to 3/16 above the bottom of the trigger bar. This fixed the false reset.

I had not touched the spring while doing the work, since I did not put in an extended mag release.

Looking at my xmas present (CZ 75 compact), it appears that at the factory they installed the spring with both sides even in height (eyeballed this, did not measure) and the spring spread such that both sides made firm contact with the frame rather than rode the center of the trigger bar grooves naturally. The gun seemed to work fine, given that it was completely stock.

It would be nice to know more about the effects of getting this thing adjusted correctly, and what kind of problems you get into when it is wrong. Maybe this is not such a big deal since you do not seem to find much written about it ?

If this is adjusted incorrectly it will not hurt anything with the gun stock.

If you work over the trigger in a fpb gun you can get a "false reset". This is where the trigger bar catches and resets in front of the sear but hasn't come far enough forward to catch the firing pin block lifter arm. Sometimes you can feel a light click (reset) when the trigger bar catches the sear. If you pull the trigger from this point the hammer will fall and hit the firing pin. The problem is that the firing pin block is still engaged. This causes the firing pin to slam into the firing pin block. This will beat up both parts. It will also cause failure to fire if shooting from reset.

I don't think most people realize that their gun is doing it since they let the trigger out past the reset point. I've felt a couple of guns that were experiencing this issue and the owners were unaware of it. I knew to look for it because a friend of mine had his gun go down due to this. I had it on one of my guns and noticed it while fitting the disconnector. David at CGW walked me through the adjustment. My second gun I used a drop in disconnector and adjusted the spring when I was doing the trigger work.

First...my personal thanks to everyone who contributed to this thread...much appreciated and very educational.

I just finished doing over my SP-01 fpb manual safety variety. Only parts I added were a CZC Comp hammer, an 85 trigger with the over travel screw and a 13 lb hammer spring. VERY pleased with the improvements in SA and DA pull weights. SA is a smooth 3.5 lbs break with just a noticeable increase in weight when the FPB lever starts to rise...I didn't polish any of those parts yet.

While filing down the safety/sear to get the safety to engage in SA with the new Comp hammer, I accidentally discovered that I have this false reset condition described above. I discovered I had two reset points but didn't realize that the FPB wasn't disengaging at the first reset point....so I have slammed my FP into the block a few times. I was about to post a thread asking if these two reset points could be timed together by some disco adjustment when I found this information above which I believe describes my situation exactly.

Am I reading this correctly that this can be overcome by adjusting the trigger bar spring to different heights on the left and right side? I did remove this and the mag release spring when I disassembled the gun as I was contemplating getting the frame refinished but decided to reassemble the gun for practice before I forgot how to put it back together. I was not aware of a difference in the two sides of this spring when I took it out....sound like it might not make any difference in a stock gun but I am scratching my head trying to understand how unequal spring pressure pushing up on the two opposite sides of the trigger bar is a good thing.....am I missing something in my analysis?

Thanks in advance for any assistance with this one....

The firing pin block lifter is on the right side of the gun (if you are looking at it from the rear). By altering the tension on the trigger bar you change when the trigger bar pushes up and catches the sear and fpb lifter.

The false reset is because the trigger bar is sliding up in front of the sear before it slides in front of the fpb lifter. You are altering that timing by changing the pressure of the spring so that both reset at the same point.

Edited February 6, 2016 by bthoefer

[tmay]

Thanks for the reply.... I think I understand the dynamics of what is occurring as you release the trigger and allow it to go forward into reset.

As the trigger bar moves forward towards the muzzle during trigger release, initiating the reset process, it encounters the sear first during its horizontal motion resetting the sear function before it encounters the fpb lifter arm further along its horizontal travel. (as you described)

I'm struggling to understand how altering the trigger bar spring pressure (which should only impact the vertical movement of the trigger bar) will change the timing of the two resets (false and actual) previously described as occurring independently along the horizontal movement of the trigger bar along the bore axis.

Unless the reduction in the spring pressure results in the trigger bar not rising enough to reset the sear (false) until after it finally reaches the fpb lifter arm (actual).

Not trying to be obstinate....really wanting to understand the actual movement and interaction of these parts during this process. I suspect this situation occurs from having installed the Comp Hammer which I believe alters the rotational position of the sear during the cocked position in SA compared to the stock hammer. I make this assumption because of the safety no longer working because of the interference of the top sear arm....so this forward rotation would position the bottom sear arm further back from its original cocked position causing it to be encountered first (false reset) by the trigger bar during the forward motion of the reset process .

Are there any unintended consequences of reducing the trigger bar spring pressure?

Curious minds want to know :-)

I am also surprised that this condition was mentioned in 2014 by you and not brought up again until Jan 2016.

Do you know if changing to a shorter reset disco eliminated this condition of the false reset?

[bthoefer]

Thanks for the reply.... I think I understand the dynamics of what is occurring as you release the trigger and allow it to go forward into reset.

As the trigger bar moves forward towards the muzzle during trigger release, initiating the reset process, it encounters the sear first during its horizontal motion resetting the sear function before it encounters the fpb lifter arm further along its horizontal travel. (as you described)

I'm struggling to understand how altering the trigger bar spring pressure (which should only impact the vertical movement of the trigger bar) will change the timing of the two resets (false and actual) previously described as occurring independently along the horizontal movement of the trigger bar along the bore axis.

Unless the reduction in the spring pressure results in the trigger bar not rising enough to reset the sear (false) until after it finally reaches the fpb lifter arm (actual).

This is correct, the trigger bar rises as it moves forward. It doesn't move parallel to the bore. Decreasing the upward pressure means the trigger bar had to come forward far enough to also reset the fpb lifter.

Not trying to be obstinate....really wanting to understand the actual movement and interaction of these parts during this process. I suspect this situation occurs from having installed the Comp Hammer which I believe alters the rotational position of the sear during the cocked position in SA compared to the stock hammer. I make this assumption because of the safety no longer working because of the interference of the top sear arm....so this forward rotation would position the bottom sear arm further back from its original cocked position causing it to be encountered first (false reset) by the trigger bar during the forward motion of the reset process .

Are there any unintended consequences of reducing the trigger bar spring pressure?

I asked David at CGW if there were any issues with doing this. He said no and it can smooth out the trigger pull a little because the spring isn't pushing against the trigger bar as hard. I've got 25,000 rounds on one gun with no problems with it. 2,000 on another with no issues again.

Curious minds want to know :-)

I am also surprised that this condition was mentioned in 2014 by you and not brought up again until Jan 2016.

Do you know if changing to a shorter reset disco eliminated this condition of the false reset?

Fitting a short reset disconnector will not change this. In fact if you hand fit a disconnector, you will see this condition as you test. The sear will reset before you remove enough material to get the fpb to reset.

[tmay]

Thanks again for your feedback.

Looks like you have gone down this path in detail yourself :-)

I have a 75B Omega that was shot so much that the trigger bar spring actually wore out and didn't lift the trigger bar enough to actually function in DA anymore....I know the trigger systems are completely different but that is what I was referring to with the unintentional consequences of lowering the spring tension in this one.

[bthoefer]

Thanks again for your feedback.

Looks like you have gone down this path in detail yourself :-)

I have a 75B Omega that was shot so much that the trigger bar spring actually wore out and didn't lift the trigger bar enough to actually function in DA anymore....I know the trigger systems are completely different but that is what I was referring to with the unintentional consequences of lowering the spring tension in this one.

The spring can / will still wear out eventually and need to be replaced. If anything the spring should last longer after getting it set up correctly since it is exerting less force on the trigger bar.

[Reverendpdp]

Ran into a problem on my do-it-yourself project. I have an SP01 manual safety that I installed a CGW Short Rest System (SRS-1), and RRK-D/C. Additionally, I replaced the hammer with a CZC comp version.

(https://czcustom.com/CZ_SA_DA-Competition-Hammer.aspx)

I followed a few YouTube videos as well as the pics in this thread. During the reassembly, everything worked fine, except that when I installed the mainspring, I lost the function of my safety. Prior to that the safety worked fine, clicking on both the up and down position.

With the slide on, the trigger functions both in the DA and SA modes, but as I said, my safety is stuck in the down position (fire). I'm trying to determine if this is a simple fix, or if I should go ahead and give it to my local smith. CGW told me to read the instructions carefully, and adjust the set screw. Only problem is I don't know which set screw they're referring to, and I might have inadvertently left it out. I have a tiny set screw that came in the packaging, but have no idea where it goes. It's smaller than the set-screw used for the trigger adjustment.

Can anyone offer any advice to this greenhorn that is in over his head?

Edited February 15, 2016 by Reverendpdp

[vixty]

Does your sear have a screw in or or the threads to add the screw

[Reverendpdp]

Does your sear have a screw in or or the threads to add the screw

No my sear is the OEM variety, with no place to add a set screw...

[tmay]

Does your sear have a screw in or or the threads to add the screw

No my sear is the OEM variety, with no place to add a set screw...

CGW makes a sear that has an adjustable set screw in it that allows you to adjust it so that the safety will work after the installation of the parts you mentioned. It is normal that the safety will no longer function after the addition of the CZC Hammer. You will have to file down the sear arm on top or the hump on the safety to get the safety to work again....this is mentioned previously in this thread...with pictures. Post #358 (page 15)

You've come this far...don't give up now :-)

Edited February 16, 2016 by tmay

[Reverendpdp]

Does your sear have a screw in or or the threads to add the screw

No my sear is the OEM variety, with no place to add a set screw...

CGW makes a sear that has an adjustable set screw in it that allows you to adjust it so that the safety will work after the installation of the parts you mentioned. It is normal that the safety will no longer function after the addition of the CZC Hammer. You will have to file down the sear arm on top or the hump on the safety to get the safety to work again....this is mentioned previously in this thread...with pictures. Post #358 (page 15)

You've come this far...don't give up now :-)

Thanks Tmay,

I broke down and ordered the adjustable sear from CGW. I wasn't aware that the hammer would interfere with safety, so i just learned yet another lesson. Thanks...

[tmay]

Excellent...would be interested to know your opinion regarding the trigger feel/weigh between the new CGW adjustable sear and the OEM sear already installed.

[Reverendpdp]

that single action looks short for a SP-01.. nice I couldn't get mine that far back.. damn good job.

Yes I agree. Is there a trick to that?

[Reverendpdp]

Excellent...would be interested to know your opinion regarding the trigger feel/weigh between the new CGW adjustable sear and the OEM sear already installed.

Well I finally got a chance to install the new adjustable sear. After watching a Youtube vid and a little playing around with it, I finally got it to where both safeties work. Now what I did notice is that the safety in double-action, allows the hammer to move reward, but just not to the point where it engages. Is this normal? I never noticed this before...

[kneelingatlas]

The safety is not designed to be used in DA, doing so can damage the sear and/or safety

[Reverendpdp]

The safety is not designed to be used in DA, doing so can damage the sear and/or safety

Oh. No kidding. Well thanks for the heads up. I wasn't aware of that.

[Reverendpdp]

SP01 Range Report: Well I finally got to take her out after adding the new trigger, hammer, adj. sear, firing pin, hammer spring, etc. The trigger felt great. In single action, it broke cleanly at about 3.25#, and about 8# in double action. The short reset was very nice too. So I ran about 200 rounds of mixed factory ammo, mostly Federal, Am. Eagle, and one box of Perfecta. The gun functioned great as was oh so accurate. I did however experience 2 oddities. Twice when I was rapid firing (double tapping actually), the gun went into double action? Now I'm still trying to familiarize myself with the gun, so I'm not sure if it was something I did? Perhaps I hit the safety, or impeded the slide? It was as though the slide didn't bring the hammer all the way back, or the hammer didn't cock. In both instances it chambered a round, so it was not a true malfunction per se, but I'm wondering if you have any insight into this? Do I need a stronger spring?

[tmay]

The same thing happened to my gun after the modifications when my wife was shooting it. It didn't happen to me though. I mentioned it to David at CGW and he knew exactly what caused it but I can't remember what he told me...what weight hammer spring are you running in it now?

Edited March 8, 2016 by tmay

[slavex]

throwing in an update to my block of suggestion from a couple years ago for driving the pins out of the hammer. CZ Custom sells a nice bench block for 30 something bucks that is an excellent addition to any tinkers bench. it has a nicely cut out hammer spot on the block that securely holds the hammer while driving out pins, and is also made so you can put the disco and strut back in and put the pins back in. It's drilled so the the pins fall into the block when driven out, and captures them until you remove the hammer and flip the block over. Great great tool. It will also hold the slide securely in cutouts and the frame laying on it's right side once the safeties are removed.

[TJART]

SP01 Range Report: Well I finally got to take her out after adding the new trigger, hammer, adj. sear, firing pin, hammer spring, etc. The trigger felt great. In single action, it broke cleanly at about 3.25#, and about 8# in double action. The short reset was very nice too. So I ran about 200 rounds of mixed factory ammo, mostly Federal, Am. Eagle, and one box of Perfecta. The gun functioned great as was oh so accurate. I did however experience 2 oddities. Twice when I was rapid firing (double tapping actually), the gun went into double action? Now I'm still trying to familiarize myself with the gun, so I'm not sure if it was something I did? Perhaps I hit the safety, or impeded the slide? It was as though the slide didn't bring the hammer all the way back, or the hammer didn't cock. In both instances it chambered a round, so it was not a true malfunction per se, but I'm wondering if you have any insight into this? Do I need a stronger spring?

You'll have to file the SA hammer shelf. I posted in your other thread.

File area 1

There is not enough of a positive shelf on your hammer SA. No fault of CZC, just needs to be fitted/tuned sometimes. Remember the CZ is a gun built with wide tolerances. Very different gun to gun.