CZ75 not resetting in double action during dry fire.

[SoCalShooter69]

11 hours ago, jinn707 said:

 

I'm curious about this.  This may sound like a stupid question - but when you say top of the disco, are you referring to the red area as shown in the picture below? Or are you referring to the nose tip of the wedge?

 

Yes, you're correct; that's exactly it.

 

That part is what rides on the under side of the sear cage. The opposite (nose) rides the frame. These are the two characteristics you manipulate to alter the timing, NOT the wing.  You want the full 90° of integrity on the wing. 

 

If a gun won't break in DA, you need the disco to sit a little higher under the cage. Conversely, if it's breaking too early, remove a small amount of material from the nose in order for it not to be pushed off the bar too soon. 

 

Great pic, btw. Thanks. 

[himurax13]

On ‎9‎/‎4‎/‎2017 at 8:18 PM, SoCalShooter69 said:

 

My point is that you shouldn't be breaking the wing at all... 

 

As I'm sure you're inclined not to believe me, since you keep telling me I'm incorrect, but you want that wing at a crisp 90*. If your gun is tuned CORRECTLY, take a little material off the top part of the disco to get it to sit a little higher under the sear cage. We're only talking .008" (if that), give or take. That will give the trigger bar the clearance it needs to fall below the wing, while still keeping a crisp, deep, and solid DA stroke. Making any modification to the wing will give you an early, and short(er) stroke in DA. That's a fact. And I'd throw that instructional picture away, it isn't very good advice. 

 

Good luck.

I respect your opinion, but I prefer to go with the advice of those who made these parts.

 

My DA stroke still launches the pencil 3 feet into the air with an 11.5 lb mainspring with a smooth 5 lb pull.

 

In either event, the issue I was having had nothing to do with the disco, LOL.

Edited September 6, 2017 by himurax13

[SlvrDragon50]

46 minutes ago, himurax13 said:

I respect your opinion, but I prefer to go with the advice of those who made these parts.

 

My DA stroke still launches the pencil 3 feet into the air with an 11.5 lb mainspring with a smooth 5 lb pull.

 

In either event, the issue I was having had nothing to do with the disco, LOL.

I've sent an email to CGW to clarify. Also, to SoCalShooter69, no one has been saying to change the angle of the wing. If you're fitting it properly, it's 90* even as you fit it.

[SlvrDragon50]

4 hours ago, himurax13 said:

I respect your opinion, but I prefer to go with the advice of those who made these parts.

 

My DA stroke still launches the pencil 3 feet into the air with an 11.5 lb mainspring with a smooth 5 lb pull.

 

In either event, the issue I was having had nothing to do with the disco, LOL.

From David:

 

Quote

In my opinion that is incorrect.  The disco is "guided" between the bottom of the sear cage and the lower shelf machined in the frame.  The disco moves laterally within the confines of these areas.  You want as little up and down disco movement as possible.

 

Consequently, if the disco is allowed to move up and down indiscriminately, the DA release point could be inconsistent and/or erratic.  

 

Trimming the discos lower wing leading edge allows you to advance the DA timing precisely and progressively.  Some CZ's can have to much DA stroke and the disco's lower wing leading edge is the logical way to correct this.  Trimming the lower wing edge many times allows the single action over travel screw to work properly in the SA mode, not the DA, as some CZ's are prone to do.

 

I have dialed in the perfect reset between the sears lower leg and the DA reset point on many competition based CZ's by properly trimming the disco's wing lower leading edge.  Removing metal from the top of the disco as you indicated simply would not allow this degree of very precise tuning.  

 

[himurax13]

Thanks for the clarification.

Sent from my VS986 using Tapatalk

[Tok36]

Interesting stuff. I need more discos to play with!

[SoCalShooter69]

That's incorrect, but feel free to use that method. 

[eerw]

 

I really like this thread.

 

just some trivia.

CZ actually has different ejector housings that have a different slopes to adjust the timing of how the trigger bar drops off the disconnector, if needed. so the issue of where to take material off is moot in the eyes of CZ UB.  That is why you will see different number values from time to time on the housing..

 

[SoCalShooter69]

This is true of tanfos, too, Stu.

 

Couple things, gents -

 

If you get a platform that won't break in DA with the aftermarket goodies, it's because the disco is pinched between the frame and the underside of the sear housing. The disco NEEDS to sit higher. The 90° wing creates a positive and crisp break in DA. When you break that angle of the wing, you're creating a "slip" off the trigger bar. That is NOT what you want. That will cause early hammer fall, and especially a lot of lost momentum. 

 

To say that the disco can't experience lateral or linear movement is just incorrect. Tanfos use a floating disco pin in the bolo. 

 

I'm not hear to say what you guys should do. I'm simply telling you the correct way to do it, if you have an oversized disco and having DA reset issue. 

[SlvrDragon50]

I don't get why you keep talkinga bout breaking the angle of the wing. No one has mentioned changing the angle of the wing. If you are filing it down properly, it remains 90* but just a shorter length.

[SoCalShooter69]

6 minutes ago, SlvrDragon50 said:

I don't get why you keep talkinga bout breaking the angle of the wing. No one has mentioned changing the angle of the wing. If you are filing it down properly, it remains 90* but just a shorter length.

 

You have reading and comprehension issue (s). From the quote above, from CGW:

 

"Trimming the discos lower wing leading edge allows you to advance the DA timing precisely and progressively."

 

He is specifically talking about breaking that lower 90° leading edge, to a more rounded or 45° angle. That's what he tells everyone that has DA no break or reset issues. It's been that way for years, buddy. 

 

[Tok36]

7 hours ago, eerw said:

 

I really like this thread.

 

just some trivia.

CZ actually has different ejector housings that have a different slopes to adjust the timing of how the trigger bar drops off the disconnector, if needed. so the issue of where to take material off is moot in the eyes of CZ UB.  That is why you will see different number values from time to time on the housing..

 

So that is what those numbers are for, i have wondered about that for a long while. I had assumed that they were numbered for some of the different model frames or pistols from different years but never tested it. Thank you for the CZ trivia.

Edited September 8, 2017 by Tok36

[GrumpyOne]

Just a reminder

 

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[858]

19 hours ago, SlvrDragon50 said:

I don't get why you keep talkinga bout breaking the angle of the wing. No one has mentioned changing the angle of the wing. If you are filing it down properly, it remains 90* but just a shorter length.

 

It appears that CZ uses revisions of the sear cage to accomplish the modification SoCalShooter69 has been recommending to the disco. I would think that if modifying the disco were correct that CZ would have various versions of the disco instead of the sear cage. Breaking the corner of the ear or reducing the ear's length may solve the DA reset but it also affects the timing of the hammer whereas modifying the top of the disco or the bottom of the sear cage does not. 

[Tok36]

I think that there are different ways to deliver information and some of the options are received better than others. Saying that one way is "wrong" or "incorrect" is unnecessary involving this topic at this point. In my case until i try it myself and converse with others who have tried it is just a new option.

[mikeinctown]

Regardless of who believe the other is right or wrong, I am wondering if the disco might be the reason I had been getting light strikes on Winchester primers even with my 11.5# main spring. After I read this thread and popped a new spring in the gun I put my Shadow side by side with my 75 SP-01 that I just installed the CGW stuff in without modification. The Shadow hammer drops significantly earlier and I can visibly see that the normal 75 hammer goes almost all the way back to the beavertail while the Shadow drops an easy couple mm earlier. (1/8" is what it looks like to be honest)

 

The gun has had a ton of dry fire in addition to about 25,000 claimed rounds and am wondering what parts I should look at ordering to freshen it up. (new disco and trigger bar?)

[himurax13]

On ‎9‎/‎12‎/‎2017 at 4:00 AM, mikeinctown said:

Regardless of who believe the other is right or wrong, I am wondering if the disco might be the reason I had been getting light strikes on Winchester primers even with my 11.5# main spring. After I read this thread and popped a new spring in the gun I put my Shadow side by side with my 75 SP-01 that I just installed the CGW stuff in without modification. The Shadow hammer drops significantly earlier and I can visibly see that the normal 75 hammer goes almost all the way back to the beavertail while the Shadow drops an easy couple mm earlier. (1/8" is what it looks like to be honest)

 

The gun has had a ton of dry fire in addition to about 25,000 claimed rounds and am wondering what parts I should look at ordering to freshen it up. (new disco and trigger bar?)

 

Is this occurring during DA or SA? The OEM hammer cams backwards before firing in SA mode.

[yigal]

On 9/7/2017 at 5:08 AM, SlvrDragon50 said:

From David:

 

 

 

[yigal]

On 9/7/2017 at 5:08 AM, SlvrDragon50 said:

From David:

 

 

exactly. cgw  instruction is o.k. they know what they do.

if you file  upper side of disco the da stroke will be inconsistent. disco run between frame and sear cage with very small space from this reason.

da  has always  shorter stroke than sa.

 

[SoCalShooter69]

9 hours ago, yigal said:

exactly. cgw  instruction is o.k. they know what they do.

if you file  upper side of disco the da stroke will be inconsistent. disco run between frame and sear cage with very small space from this reason.

da  has always  shorter stroke than sa.

 

 

Everything you wrote is incorrect. 

[yigal]

3 hours ago, SoCalShooter69 said:

 

Everything you wrote is incorrect. 

 thank you. 

the way u suggested to solve the problem will work but i don't like it.

 

Edited September 21, 2017 by yigal

[mikeinctown]

On ‎9‎/‎20‎/‎2017 at 1:38 AM, himurax13 said:

 

Is this occurring during DA or SA? The OEM hammer cams backwards before firing in SA mode.

 

Sorry, just had a chance to take a look this morning. The difference is in DA. In SA the hammers appear to cock back the same distance.

[yigal]

1 hour ago, mikeinctown said:

 

Sorry, just had a chance to take a look this morning. The difference is in DA. In SA the hammers appear to cock back the same distance.

front of me i have cutaway  of tan. frame with marked distance for sa stroke  and da  (standard parts not modified)

da stroke shorter  around 1.5 mm than sa.  my old cz 75 works  same.

trigger works perfect.

Edited September 21, 2017 by yigal

[mikeinctown]

3 hours ago, yigal said:

front of me i have cutaway  of tan. frame with marked distance for sa stroke  and da  (standard parts not modified)

da stroke shorter  around 1.5 mm than sa.  my old cz 75 works  same.

trigger works perfect.

 

It's not about the distance between the DA stroke and the SA stroke, it is the distance between a used Shadow hammer in DA and a CGW SP-01 non shadow gun with the hammer in DA and SA. In SA both the shadow and non shadow appear to be in the same location, but in DA the Shadow Target hammer drops noticable sooner. Perhaps this is a "feature" of the CZC action jobs they perform on their pistols and as mine just has the CGW pro package without any additional work done besides polishing, perhaps that could be the difference. I was just wondering because I was getting light strikes on Winchester primers with the 11.5# hammer spring about 1-2 per 100. Perhaps the firing pin tip is just getting worn. I'll just order a new one as they are $20.

[SoCalShooter69]

5 hours ago, mikeinctown said:

 

It's not about the distance between the DA stroke and the SA stroke, it is the distance between a used Shadow hammer in DA and a CGW SP-01 non shadow gun with the hammer in DA and SA. In SA both the shadow and non shadow appear to be in the same location, but in DA the Shadow Target hammer drops noticable sooner. Perhaps this is a "feature" of the CZC action jobs they perform on their pistols and as mine just has the CGW pro package without any additional work done besides polishing, perhaps that could be the difference. I was just wondering because I was getting light strikes on Winchester primers with the 11.5# hammer spring about 1-2 per 100. Perhaps the firing pin tip is just getting worn. I'll just order a new one as they are $20.

 

The nose of the disco that rides the frame is too long/tall. The frame is forcing the disco up and off the tigger bar too early. The disco needs to ride that portion a little more before its pushed off. If you take, say, 008 - 010" off the nose of the disco, I can guarantee you, you'll get a DA hammer that goes back and damn near touches the beaver tail. That being said, .008 - .010" is just my personal experience. If you decide to do this, I'd go in .004 increments.