Failure to go into full battery - CZ40P

[tdogg]

First off let me introduce myself,

My name is Toby and I have a gun problem .  I am new and have been lurking around for a month or two.  I just purchased a CZ40P from a friend cheap.  He got it in a trade so he didn't know too much about it.  After reading a bunch here, I have done some upgrades:

A stainless rod
Wolff recoil spring kit 18, 20, and 22 lb (only tried the 22 lb thus far)
Wolff mag springs (+10%)
Lightly polished the feed ramp
Cleaned and lubed after every outing

Here is my problem:

Frequently (several times per magazine lately) it doesn't go into full battery.  The slide hangs up about 3/16 of an inch short.  Sometimes you can gently tap/push it into full battery and sometimes it gets jammed as such you can't get the slide to move.  In the latter case, I drop the magazine, decock the gun, and have to use two hands to get the slide to move (trying to eject the round).  Needless to say I can't rely on this gun yet...

It fails with both (original) magazines and with the wolff springs installed.
If fails with the original recoil spring and the heavy wolff spring.
I have cleaned, inspected, and lubed this gun several times during my troubleshooting activities.
I've tried several different brands of FMJ ammo (white box 165gr, Federal 180gr, Independent 180gr) and there was no change in the frequency

It seems that the barrel is getting hung up as it try's to lock into full battery.  That last little bit that the barrel rises to lock into full battery is not happening smoothly.  I can't see any damage or wear that would point to what is causing it to fail. 

Does anyone have any thoughts or ideas about what is happening?  Anything to check or inspect?  I probably will take this gun into my local shop but I thought I would ask here in case there is something I have missed.

Thanks in advance,
Toby

[tdogg]

So I just noticed that my firing pin block lever spring is missing.  I have'nt taken this apart so it must have either failed or the previous owner neglected to put it back.  I also noticed the firing pin block lever is fairly chewed up on the end.

This has to be causing the firing pin block lever to hang up under the firing pin block when the slide returns back to full battery.  I need to order a new spring, reassemble, and figure out if this was the actual cause.

Fingers crossed.

Toby

[tdogg]

Well I pulled apart the entire gun.  I couldn't see any modifications to the gun indicating that the firing pin block lever spring must have failed?  It is a tiny little spring.

I replaced the firing pin block lever, firing pin block lever spring, sear, sear spring, sear pin, and decocking lever spring.  I didn't need to replace the sear or the sear pin but now I have spares.

Here is a before picture, notice how the firing pin block lever is standing straight up?  There is no spring to keep it in the down position.


Here is the ejector box pulled from the gun, it is still assembled with a slave pin.  Notice how the firing pin block lever is chewed up on the end.


Here is the ejector box with all the new parts installed.  It really is a pain in the ass getting all the springs, decocking lever, sear, and firing pin lever together at once.  With a little patience, three hands, and a couple of punches to hold things together as you get springs in their place, it will come together.


Here it is in the gun:


While I was in there I polished the trigger bar and the ejector.  I meant to take pictures of those but forgot and put it all back together.  Now all I need to do is go out and see if it's fixed.  I plan on going out this weekend.  I picked up 200 rounds of Federal 180gr.

Fingers still crossed.

Toby

[Grendel]

Nice job on figuring it out and kudos on posting the pics to help the next guy to have the problem. Welcome to the forum.

[tdogg]

It's working!

I just went out and put 60 rounds and had no issues with the slide hanging up.  I did have a couple of FTF's but I think it was a magazine issue.  I didn't have any issues with the other magazine. 

I ran both WWB and Federal.  The WWB will not consistantly lock the slide open on emtpy.  The Federal didn't have a problem locking the slide open.

Hopefully all the kinks are worked out now and I can work on getting more brass through it!

Cheers!
Toby

[AZ_CZ]

That is great news, great job getting that figured out,

[tdogg]

Went out with a few folks last weekend and put about 150 rounds through it.  I had two FTF's but it could have been the crappy weather (40 mph winds, sprinkles, and dust) or one of my magazines?  I did wipe the feedramp with my finger and didn't experience another afterward, so maybe it was just that dirty?

I can't believe how accurate this gun is, I was hitting (stationary) clay pigeons at 10-15 yards one right after the other.  I was taking them faster then my friends could acquire the target and pull the trigger (they would get frustrated and wait for my clip to empty before trying ).

The gun feels great in my hand even though it is a compact frame.  I can't wait to get a full size frame (for my big hands) to see how much better it fits.  Apparently the SP-01 tactical's are returning this Feb. and that will be my next purchase (unless I find a clean used 9mm model before then).

I feel like I stole this gun, it's cheap, accurate, and reliable (FTF work in progress).

Cheers!
Toby

[kobus]

wel done Toby and thanks for posting the pics.  i am glad you got your pistol sorted out.