Possible issue with the P10C safety

Discussion in 'General Firearms Forum' started by checkyoursix, Aug 29, 2019.

  1. checkyoursix


    Likes Received:
    Dec 15, 2009
    I read this post on Reddit, and I share it here for people to decide for themselves if this is an issue. Personally I don’t have a dog in this fight, sold my P10C time ago because... never mind who cares.

    So here it is, a detailed explanation supported by videos on the efficacy of the firing pin safety in this series. Sorry, long read, I have to break it down in two posts because otherwise it exceeds the maximum length allowed.
    I had a few people ask me to post some findings of testing I had done on the safety system on the P-10C and this seemed like as good a place as any. Keeping in mind this is a sample of 1 pistol with a few hundred rounds through it, I have seen lots of mentions of this same problem online.
    There has been a lot of discussion and concern about the function of the firing pin safety on the CZ P-10 series of pistols. It seems to be a common issue on these pistols that the striker block has marginal engagement on the striker, so I set out to do some testing. After some analysis I’ve come to the conclusion that there appear to be real safety concerns with the design and/or manufacture of this specific feature of the pistol. This ended up a bit wordy, but I found this really interesting and fairly concerning.


    The pistol was partially disassembled and observed in motion in order to fully understand the operation of the firing pin safety system. A test was also carried out to determine the level of functionality of the system in case of a failure. Conclusions lead me to believe that the firing pin safety is of (at best) only marginal usefulness and very close to completely non-functional.

    Description of safety system function:
    On many modern pistols, eg. Glocks, M&P, etc, there are at least three automatic safety systems – the Trigger Safety, the Drop Safety, and the Firing Pin Safety. The Trigger Safety is easily visible on most designs, the one on the P-10 being the smaller “Trigger within a trigger” that is depressed by the shooter’s finger. The Drop Safety is internal, and on most designs is comprised of a shelf that the trigger bar must pass before being allowed to drop. This safety, in conjunction with the trigger safety, effectively prevents the striker from being released if the pistol is dropped. The Firing Pin Safety is a mechanical block that prevents the firing pin/striker from traveling forward far enough to contact the cartridge primer and firing. Should the firing pin/striker become disconnected from the trigger bar interface or break in such a way it would travel forward on spring tension, this is the safety that would stop its movement. On most pistols, this block is contained within the main body of the slide – the design on the P-10 is much different. Contained within the striker housing is a block that is held against the shaft of the striker under spring tension. When engaged, a small nub on the block interferes with a shoulder on the striker to impede its forward movement. When the trigger is pulled rearward, a triangular shape on the trigger bar rotates this block out of the way, clearing the path of the striker. At the end of trigger travel, the trigger bar drops down into the frame and the striker flies forward under spring tension, hitting the primer and setting off the cartridge. The slide travels backwards under force of recoil and trips the disconnector, allowing the trigger bar to raise far enough to catch the tail of the striker as the slide comes back forwards.

    As a point of clarification – many have referred to post #17 of this thread at CZForums as an explation of how this safety system works: czfirearms.us/index.php?topic=103705.15. This explanation (purportedly from a CZ representative) appears to be entirely incorrect. At no point does the triangular nub of the trigger bar fall low enough to disengage from the leg of the striker block. The triangular nub is angled on the top for clearance purposes ONLY, it does not positively hold the striker block in place at any point of its travel. The striker block is pushed into its engaged position ONLY by the force of its small spring.

    Video explanation of how the safety actually works here - www.youtube.com/watch?v=lo0fQ08n_UI

    Test #1 – Slide only:
    To determine the effectiveness of the firing pin block, the slide was removed from the pistol and placed in a vise padded with a towel. The striker was pulled back to varying distances and released after verifying the striker block had traveled to its full extent of engagement. At each distance the striker was pulled back, even very small distances, the striker was able to easily overcome the block and simply push it out of the way. Video here - www.youtube.com/watch?v=rKIUpTDbn6o
  2. checkyoursix


    Likes Received:
    Dec 15, 2009
    This is part two of the previous post.


    Test #2 – Primed Case:
    An empty 9mm cartridge primed with a CCI primer was placed in the barrel, which was installed into the slide with the recoil spring holding it in place. The striker was pulled back to varying distances and released after verifying the striker block had traveled to its full extent of engagement. At small distances, the cartridge case did not fire. At any distance greater than about 75% of the striker’s maximum travel, the primer ignited almost every time. Video here - www.youtube.com/watch?v=ezFV4yWMNpk

    The firing pin block does not appear to serve as a functional stop to the travel of the striker. At best, it slightly reduces the velocity of the striker before impacting the primer. Several things seem to be contributing to this problem. Firstly, the engagement surface between the striker block and the shoulder on the striker is extremely small. This shoulder on the striker has a small radius at its root (likely necessary for the MIM process and to reduce stress concentrations) and this radius serves as a ramp to push the striker block out of the way. The striker can also rotate a bit in the striker housing, making an inconsistent engagement between the striker and the block.

    It should be kept in mind that this is not the only safety system on the P-10 series of pistols. Even without a functional firing pin safety, the chances of an accidental discharge caused by mechanical failure is very low. The trigger safety and drop safety, in my opinion, still make this a relatively safe design. Even in a theoretical case in which the striker became detached from the trigger bar (due to disengagement or breakage) the striker is only half-cocked or less when the trigger is forward. In my testing, the striker had to be drawn further to the rear to set off the primer. Softer primers, such as Federal, may have been set off closer to half cock, but these were not tested.

    Despite the fact that the P-10 is likely safe, these conclusions have led me to make the decision to relegate this pistol to range use only. I would not feel comfortable carrying a pistol with what I consider to be a defective safety system.

    I sent an email to CZ this morning with a link to this thread and here was the response from one of their lead support guys:
    "Good afternoon,
    The automatic safety or the “firing pin block” cannot be checked by having the slide out of the frame, as the components internally will retain this part in place until the trigger is in the rearmost position to allow the safety to move out of the way, freeing the path for striker to move forward.
    Attempting to test this as one would a traditional firing pin block will produce a false result. There is no test that can be done at home to verify function of this part without a physical drop test which for safety and potential finish damage reasons we cannot recommend.
    Should you have any concerns or issues with your firearm please let us know and we can have the firearm sent in for a safety inspection."
    In inspecting further, I do not think this is correct. I see nothing in the frame that would serve to positively locate the firing pin block with the trigger forward and am still convinced it is held in place only by its spring. I'll take another look at it tonight, in the meantime I've sent an email back to him asking him to clarify which part is supposed to keep the block in place.
    EDIT 2
    After more study of the system I am 100% sure the rep at CZ that responded to me is incorrect on how the system functions. The striker block relies one hundred percent on spring tension at all times and is never prevented from rotating out of place by mechanical locking. It's clear from just looking at the frame with the slide off that there are no other components that could possibly keep the striker block in place, but just to be sure, I put the slide on the frame and tested.
    Video here - www.youtube.com/watch?v=nN7cbTSwR4A&feature=youtu.be
    EDIT 3
    For those who are still skeptical, user Rin_Rans_reddit went to the trouble to create an "armorers plate" by cutting the bottom portion of his slide cover off. In his video you can see the ENTIRE pistol assembled, there is nothing locking the firing pin block in place - spring tension only.
    EDIT 4 8/23/2019
    I finally heard back from a CZ rep about this. Super long response from him below:
    Apologies for the slow reply, I used the time to visit with engineers and designers both in the US and in the Czech Republic as well as to review engineering drawings, testing procedures and their corresponding results.
    We greatly appreciate your concerns, but we are confident that the comprehensive safety systems that are incorporated into the P-10 platform are more than robust enough to keep our customers safe while properly handling and using them. Not only have our factory’s designers performed extensive testing of these safety systems during development, they continue to perform those tests at regular intervals during production.
    Outside of the factory, we’ve also employed the services of an NIJ-certified independent third party to perform testing to the P-10 platform in accordance with NIJ-STD-0112.03, Autoloading Pistols.
    During this outside testing, P-10s of various configurations/models were subjected to extremes of temperature and environment like sand, salt water immersion and more. Another aspect was extensive rough handling and drop tests. In those tests the P-10 performed as we knew it would – experiencing no failures.
    The main safety systems, as you’ve mentioned in your write-up, are the trigger safety and the drop safety. Both of these mechanical safeties work to prevent the P-10 from firing without the trigger being pulled.
    The safety in question is a third safety, known as the ‘automatic safety.’ For the automatic safety to ever need to be employed, either the firing pin, the sear surface of the trigger bar, the trigger bar spring pin or the frame itself would have to fail. In the incredibly rare instance of one of these items failing, the role of the automatic safety is to reduce the chance of the firing pin igniting a chambered round, adding a third layer to the robust safety system within the P-10.
    There are many factors present in the 'testing' in question that are not able to be present in the P-10 during use in its assembled form. First and foremost, the firing pin travel exhibited in videos of these ‘tests’ is far greater than the maximum firing pin travel reached during the normal cocking/firing sequence (to the tune of 1.5x, resulting in a corresponding increase in inertia within the firing pin).
    Realistically and in the worst case scenario, were a failure to happen the firing pin would be falling from its pre-cocked position with far less force, allowing the automatic safety to retard its forward travel. When in the pre-cocked position, the firing pin still has 3.5mm to travel before achieving its full travel and being released by the trigger bar.
    A major factor in all of this is that the designers of the P-10 intended this tertiary safety to function once and as a last resort were a parts failure to have occurred, envisioning it much like an airbag in a car. During normal use of the firearm, the automatic safety never impacts the corresponding shoulder on the firing pin. As such, when called upon those two engagement surfaces are able to make positive contact, hampering the firing pin's forward progress.
    Subjecting the system to non-standard testing such as this will in no question create undue wear to those engagement surfaces, and the more times the test is repeated, the less chance the automatic safety will be able to perform its function in the rare instance it were needed. Fully withdrawing the firing pin to that overdrawn position will exacerbate this greatly.
    Like in other instances where faulty information on the internet has led folks to perform ill-advised 'testing' that ends up damaging guns, we're happy to support CZ owners and provide them with factory original parts that will function as intended in the rare instance they'd be called upon.
    As with all CZ firearm designs, safety and reliability were key parameters from the get-go with the P-10 series pistols and we would never compromise on those aspects. Thorough testing both internally and externally with independent third parties reaffirms that the P-10 family of pistols meets and exceeds the safety demands we and our consumers put upon it.
    Thank you!"
    TL,DR: "It's fine, don't worry about it.



    Likes Received:
    Aug 20, 2005
    This sounds like someone looking for a problem.
  4. ithaca_deerslayer


    Likes Received:
    Jul 11, 2000
    Upstate NY, USA
    So the summary seems to be that some dudes took apart their gun and flung the firing pin farther and faster than would happen in real life, and determined the internal safety didn't stop it good enough.

    CZ seems to be saying, you can't test that way. Slide needs to be on gun, and the firing pin travel and speed regulated to real firing of the gun. They've tested extensively and see no signs of failure.

    Seems fair enough. I wonder why the design doesn't just block the firing pin completely, in the first place, like with a Glock?
  5. Gfive45


    Likes Received:
    Apr 2, 2014
    I highly recommend looking for the latest models #91531 #91532 from >2019+ with the swappable wider mag release and the little square notch in the right side of slide cover back plate, have already been fixed.

    Last edited: Sep 11, 2020
  6. bac1023


    Likes Received:
    Sep 26, 2004

    Don’t affect me either. Never been a fan of that pistol.
  7. WayneJessie


    Likes Received:
    Jan 12, 2013
    I agree and I own an early version of the gun. I know mine has at least 5K rounds through it and possibly more. After all those rounds Ive unintentionally dropped it loaded and ready to fire.How long did it take before Sig 320 pistols were discovered to have the issue with being unsafe if dropped? It wasn’t long. If the P10 was potentially unsafe someone would’ve figured out how to replicate the issue by now.
    Though I don’t think the P10 is perfect, I do accept that it’s as safe as any other striker fired pistols on the market. I believe CZ is reputable enough to fix any such issue as serious as that. They’ve been a stand up company for a long time.