CZ97b hammer movement while on safe

[Dan Wesson]

I have a CZ97b with the stock manual safety from the factory installed.  It works just fine, but it bothers me that the hammer moves back a bit while the gun is on safe, and the trigger is pulled.  I guess I'm used to my 1911s where the sear is totally blocked and the hammer does not move at all (that I can see) when the gun is on safe and the trigger is pulled.

Is it normal that the hammer can move a bit while the safety is fully engaged?  Or do I need a new safety lever to be fit more exactly?  I've been thinking of lowering the hammer hooks a bit to reduce creep, but not if the hammer already moves a bit while on safe!

[SI VIS PACEM PARRABELLUM]

Yes it's normal. This can be seen across the entire CZ B series line not just the 97B. I can see movement on my 75B Compact and full size 75B as well.  Nothing to worry about but just like a 1911 you don't want to be intentionally pulling the trigger when on safe or you can induce a problem.

[Dan Wesson]

Thanks for the info.  My concern is that on a 1911, such movement is not normal, and could possibly leave the gun in a very unsafe condition. (see Safety Test excerpt from Cylinder and Slide:  The next check is to determine if the thumb safety is holding the sear from partially disengaging from the hammer. ( I call this the click test - and remember - DO NOT TOUCH THE TRIGGER after disengaging the thumb safety.) After disengaging the thumb safety, place the hammer area of the pistol close to your so that you can hear the slightest click when you run this test. With the hammer area of the pistol held close to your ear, pull the hammer to the rear very slightly. Do not touch the hammer at all until you have placed the pistol near your ear. If you hear a very slight click when you touch the hammer this is the sound of the sear jumping back into full engagement with the hammer full cock hooks. Remember, you must engage the thumb safety, pull and release the trigger, disengage the thumb safety, holt the pistol near your ear, and then just touch the hammer slightly to the rear. If you hear a click the safety is allowing the sear to move slightly out of engagement with the hammer. The hammer hooks that the sear engages with are only .022" thick as made at the factory and if the pistol has had a trigger job done the hooks could have been shortened to .019". Any movement of the sear could leave the sear engaging the hammer with only a few thousandths. NOT SAFE! If you hear a click you must have the safety replaced or welded up and re-cut to stop any sear movement with the thumb safety engaged.)

I fully understand that the sear engagement geometry on a CZ is DIFFERENT than a 1911 and that because of the angle, the sear and hammer move back to the at rest position when I release the trigger on my 97b while on safe.  The hammer movement just bothers me.  Has anyone had a CZ with a manual safety that fully blocks sear and hammer movement when on safe?  I would like to know.

[SI VIS PACEM PARRABELLUM]

I fully understand the difference between the 1911 safety which blocks sear movement and why EXACTLY sear movement on that gun is unsafe and the completely different CZ lockwork.Best advice would be for you to study schematics of the two designs and gain an understanding of exactly how they function differently  Otherwise you'll never be at ease with the 97.

[Dan Wesson]

I do understand it.  And I am comfortable with carrying a CZ pistol cocked and locked.  I was probably not clear in my post.

I just wondered if having a non-moving sear, when on safe, is desirable on a stock sear/hammer combo.  If camming back is simply a "feature" of the CZ set-up, I get that.  I do know that using a competition hammer with a different sear engagement angle can yield a setup that does not cam the hammer back.  I also know that people send their pistols to CGW to get the camming back and creep eliminated.

To clarify:  Is this "cam-back" on safe just the way the stock hammer-sear-safety works, or is it possible to fit a safety so the camming back (and slight movement of the sear cage) is eliminated from the stock sear/hammer when the gun is on safe?

I suppose I'm just fishing for details now.  The standard set up is entirely safe as it functions... I guess I'm wondering if the slop in the sear/hammer/safety when on safe is just a tolerance/design point.

I hope that makes my thought clearer.  Thanks.

Thank you for trying to help me out.

[Tok36]

I do understand it.  And I am comfortable with carrying a CZ pistol cocked and locked.  I was probably not clear in my post.

I just wondered if having a non-moving sear, when on safe, is desirable on a stock sear/hammer combo.  If camming back is simply a "feature" of the CZ set-up, I get that.  I do know that using a competition hammer with a different sear engagement angle can yield a setup that does not cam the hammer back.  I also know that people send their pistols to CGW to get the camming back and creep eliminated.

To clarify:  Is this "cam-back" on safe just the way the stock hammer-sear-safety works, or is it possible to fit a safety so the camming back (and slight movement of the sear cage) is eliminated from the stock sear/hammer when the gun is on safe?

I suppose I'm just fishing for details now.  The standard set up is entirely safe as it functions... I guess I'm wondering if the slop in the sear/hammer/safety when on safe is just a tolerance/design point.

I hope that makes my thought clearer.  Thanks.

Thank you for trying to help me out.

Do to the design some slight movement in the hammer is normal. Even with upgrade parts it is generally the same. As long as the safety is functioning properly i suggest putting the hammer movement to the back of your mind.

[Dan Wesson]

Will do.  I guess that confirmation was what I was looking for!

[newageroman]

I'm fitting a safety on an SP-01 right now. It works, but there is more movement that I would like, and a bit of slop too. The Adjustable sear might help.

[tdogg]

New age beat me to it.

There is an adjustable sear from CGW that you can take most of the slack out of the action when the safety is engaged.  Some words of caution though on fitting a safety.  I just installed 2 new shadow 2 extended safeties on my TSO's.  One did not need any fitting the other required a slight amount of fitting to be able to engage the safety.  At first I didn't want any free play and I fit the sear to safety very tight.  I could actuate the safety but it was very tight against the sear leg.  I found out at my local match that there is such a thing as too tight as I couldn't engage the safety mid way through the match!  Fortunate for me this was during the make ready command and I had all the time needed to fix it.  I had to clear the gun and cycle the action many times for the grit or whatever was blocking the sear engagement to clear itself. 

I have since refit the sear to safety and it has more clearance.  I'm confident that the safety design is sound and when engaged will not let the hammer fall.  This in on gun with a very crisp sear to competition hammer hook interference.  As long as the clearance/movement isn't too excessive it should be safe.

Cheers,
Toby

[Dan Wesson]

Excellent. No worries. Another confirmation that the design seems to need that “slop” as you documented.


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[Rmach]

I just checked one of my stainless 75's, and yes, the hammer moves a bit with the safety on.