Remove CZ-85 Hammer?

[bountyhunter]

CZ-85 Hammer Removal?

I have a CZ-85 Combat. I want to shorten up (and clean up) the SA trigger break. I have the only manual available, but it is for the CZ-75. I noticed an important difference between the manual and my CZ-85: the safety detent spring assy is not as described and I am afraid to pull the safety lever and launch the detent spring(s) into oblivion. How are the detent springs held in? Anybody know if removing the safety/sear assy will send them flying?

Please explain for the CZ-85:

1) Is it required to remove the safety and sear/ejector asembly prior to removing the hammer? I ask because:

I see the retaining pin that holds in the hammer mount (pivot) pin. It says to drive the retaining pin upward to enable removal of the hammer pivot pin, but it appears the sear/ejector assy blocks the retaining pin from going up. I tapped it lightly but it would not go up. Am I correct that the sear/ejector must come off first or is there a way to get the hammer off without removing the sear and safety?

2) As for shortening the SA pull, the height of the full-cock notch on the hammer clearly has some room for removal of material to shorten the SA trigger break. Any suggestions about how much to take off the top of the hook?


FYI: I noticed that the "safety" hook on the hammer in my gun is about 1/2 as tall as the full-cock hook... rather odd, as on most guns the safety hook is a shade taller to ensure catching the sear if the hammer follows from the full cock notch. Important in case anybody had considered putting a "relief" cut on the sear, as the sear would probably work perfectly with the full-cock notch but not capture the safety hook (very dangerous). Looks like the sear should be left alone (just polish the face).

I would appreciate any advice on the subject of sear/hammer mods for the typical trigger job from those who do them. I have done many, but none on CZ's.

Thanks.

 

[Chris Rhines]

Okay, the following advice is based only on my experience. I'm not responsible for lost parts, damaged firearms, or extra holes in one's decor or anatomy.

First, you will have to remove the ejector block to get the hammer pin out. Retract the safety detent with a pin punch and tap the safety pin out. The sear spring may well go flying when you do this, so keep a hand over the top of it. The detent/detent spring usually does not come out easily.

Then, push up the hammer retaining pin and push out the hammer pin.

What I did to clean up my CZ trigger - I polished the trigger bar, sear engagement surfaces, hammer notch and hammer face. I cut the hammer hooks down a little bit, not sure how much (I was going by cut and try.) I wouldn't suggest changing the engagement angle between the sear and hammer - you could end up with a hammer that slips off the sear under recoil.

That and a Wolff spring kit got my CZ-75 trigger where I wanted it. Go slow, and be careful. Let us know how it turns out.

- Chris

 

[bountyhunter]

Thanks for the info. If I read your post right, you worked on a CZ-75? I've got thr manual for that one and I understand the detent plunger/spring setup. It's in front of the safety and you can put a "holding pin" in to capture the plunger from above with the safety rotated to push the plunger in fully.

The problem is: the CZ-85 has the detent parts rear of the safety. It appears to be part of the sear assy, and I don't have a clue how it goes together. There is a piece on either side that moves when you rotate the safety, but I can't figure out where the spring or plunger is or how to capture it.

 

[braindead0]

could end up with a hammer that slips off the sear under recoil.

Woopies, inadvertant full auto

 

[Chris Rhines]

Bountyhunter -

The plunger is in the frame of the pistol, just behind the safety. You should be able to see it move when you move the safety on and off. When you draw the little plunger back with a pin punch, you should be able to pull the safety out.

I think that the CZ-85 has a detent on each side, ambi safety and all, but I'm not 100% sure.

- Chris

 

[bountyhunter]

Chris: you are correct. The detent plunger is held captive in the frame on both sides behind the safety levers (one on each side). You force them back using the notches on the top and then work the safety out. I just wasn't sure if the plungers stayed captive after the safety lever came out. I went ahead and tried it and they did. Thanks, you are the only person on about five different forums (including the CZ forum) that gave me the right answer. You have obviously done it before.

 

[Chris Rhines]

BH -

Thanks. I've had, in the past, four CZ-75s, and all of them have been worked on to one degree or another. Love 'em to death. Simple, reliable, accurate, ergonomics are off the hook.

One thing that I have noticed, though, is that there is a distinct lack of gunsmiths who work on -75s. I can only think of three off the top of my head (Mike Eagleshield, Evolution Gun Works, and Dlask.) There isn't even alot of information out there on how to work on the CZ-75, with regard to sear/hammer engagement, pull weights, slide machining, spring weights, etc.

Reason I bring this up is that I wonder how many CZ owners would be interested in a really good gunsmithing manual on the -75.

Anyhow, good luck with the -85C. Let us know how it works out.

- Chris

 

[bountyhunter]

"There isn't even alot of information out there on how to work on the CZ-75, with regard to sear/hammer engagement, pull weights, slide machining, spring weights, etc."

AMEN. I am making it up as I go along. I can see by the amount that the Hammer deflects rearward during an SA pull that the sear angle is pretty steep. I am sure you could flatten it out a bit and still get reliable hammer face capture, but I didn't change the angle on mine. I just polished it mirror smooth.

The hammer is funny: the full-cock hook seems to be about .050" tall (stock) and the "safety" notch is maybe .020" tall. Of course, the safety notch has a "ledge" on it so it really catches the sear nose securely.

On my hammer, I cut the full-cock hook height down to about .040" and polished the faces. I just wanted a smoother, shorter SA release. Worked pretty well, the SA pull is a smooth 3.5# and breaks sharp.


"Reason I bring this up is that I wonder how many CZ owners would be interested in a really good gunsmithing manual on the -75."

I have the official CZ-75 manual and it is very brief. I got it from CZ-USA. I would love to have a good manual for my 85.