PSA - The P-10C Appears to have no functional firing pin safety

[inferno451]

I had a few people ask me to post some findings of testing I had done on the safety system on the P-10C on the CZ-specific forums. I really think this is something people need to be aware of. Keeping in mind this is a sample of 1 pistol with a few hundred rounds through it, there seem to be a lot of mentions of this online.

Original writeup from Reddit starts here:

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.

Abstract:

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: https://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 - https://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 - https://www.youtube.com/watch?v=rKIUpTDbn6o

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 - https://www.youtube.com/watch?v=ezFV4yWMNpk

Conclusions:

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 still relatively 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.



EDIT

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 - https://www.youtube.com/watch?v=nN7cbTSwR4A&feature=youtu.be

[JethroBusch]

Thank you for taking the time to both perform the tests and provide this awesome write-up. I love this pistol. It remains my favorite striker fired pistol from a handling a shoot-ability perspective. However, I don't want to AIWB a pistol that is "probably" safe. For now as a result of following this from your original posts, I've switched back to my PCR. What I want is for CZ to specifically clarify, maybe even with a cutaway version, the mechanism inside that positively locks the firing pin block into place. I agree with your assessment that unless there is a secret trap door where a gremlin emerges from, I don't see any mechanism inside that positively locks the block. I want this gun to work, and I want it to be my carry, but it won't be as long as this issue is unaddressed.

I read CZ's reply, and if they won't take action to either physically show how the lockup happens or issue some kind of fix, it might be worth raising this issue on  a few other forums like gunboards for wider distribution and visibility. Reaching out to some gun youtubers might also help put some additional pressure on them to provide more than an "it's fine but you can't tell from home" reply. I'm not trying to trash this pistol or CZ. Hell, I wanted one of each in the whole family, but I'm not ok with carrying this myself, so in it's current form it's just a range toy for me. I would have gladly paid $100 more than I did for this pistol to have a proper block system.

[armoredman]

I would hazard a guess that a company with decades of experiencing in making firearms world wide might have a pretty good idea how their firearms work. They also had the example SIG made to make sure this sidearm does not drop fire. I have not heard anything from anyone stating that their P-10 of any make has drop fired - do you have a link to a reputable source where one has done so, such as a news story or a video of one drop firing? I already put one rumor to rest with my first Gen P-10C about the infamous striker deal, but I REALLY don't want to drop my gun on concrete just to prove this one either. Perhaps CZ-USA can offer more information other than a video of a partially disassembled firearm being manipulated by an inserted tool.

[inferno451]

Armoredman,

I'm not aware of any actual problems being caused by failures of this system. Statistically it's unlikely there ever would be. I just want to bring attention to the fact that a safety system CZ thought important enough to include in their design does not appear to actually work. Even without a striker block, a striker fired pistol is probably more safe than (for example) a series 70 1911.

As to CZ understanding their design, I'm honestly not sure what's going on. The information given to me by the CZ customer service rep is clearly not correct as evidenced by my videos. In addition, the description of the way the striker block works given to the forum member in the thread linked in my post also seems to be wrong. If I had to guess I would say that maybe this pistol was designed by CZ-UB and communication between their engineering team and CZ-USA has been poor. With all the "Teething issues" the P-10C has had I think it would be difficult to argue CZ did sufficiently thorough testing on this pistol before release, and this may just be something that slipped through the cracks since it doesn't cause any observable problems.

I'd love to be wrong about this, but I don't see where I would be. I'd really appreciate to hear your feedback on what I might have missed.

[Mjolnir]

Try a rubber or polymer mallet.


Sent from my iPhone using Tapatalk

[Walt Sherrill]

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.

Since I started this reply, I got a notice that another entry had been made, and while looking for it I found a good explanation by Hickeroar about how the P-10 safety mechanism works.  His reply basically says the same thing I say, below, but does it more succinctly,  Here's a link:  https://czfirearms.us/index.php?topic=103705.15   It's reply #17.    But in hopes of making  things more clear, I'll still post my reply.

As best I can tell, the CZ-P10 striker assembly works a bit like a Glock striker assembly.   In fact, if you compare the striker assemblies of the two guns, they are very similar.  How the strikers are actuated is slightly different, but the results are similar.

With the CZ The vertical part of the trigger par (part 7 in the parts diagram) pushes the striker back until it reaches a certain point and it then as the trigger bar movement continues the striker is released by the rear of the trigger bar dropping slightly.  With the Glock, the striker is engaged on the side, but works in a similar manner. When the slide has been moved (as in chambering a round or firing one), the spring is again partially compressed, awaiting the next trigger pull.  But just pushing the trigger forward has no effect on the striker spring, so there is no second-striker capability.

When the CZ striker assembly is at rest (i.e., it hasn't been compressed further by trigger bar movement), the striker is resting on a partially-compressed striker spring. 

When the trigger bar hasn't been moved to the rear, that vertical part on the CZ trigger bar (which is used to push the striker back) also acts like a stop.  If the gun is dropped, and there's no trigger finger pressing the trigger to compress the spring, the trigger bar will return to it's at-rest position.  If the drop is forceful enough to actually power the striker, the vertical part of the The trigger bar then keeps the striker (CZ calls it a firing pin) from moving far enough forward to ignite a primer.  Unless the spring is fully compressed, by slide action and trigger bar movement, the striker doesn't have enough inertial force to do anything, if the gun is dropped or struck,  and the trigger bar itself acts like a firing pin stop.

Your test shows what happens when the striker is nearly fully charged, which it would never be if dropped or struck, with the slide off the frame, it will ignite a primer.  And it SHOULD!

Your test seems to show that if the striker is only partially charged (as would be the case if the gun is dropped), or at rest (the round was a dud), nothing is going to happen.  I think the vertical part of the trigger bar will also keep the pin/striker causing an inertial strike on the primer. 

I think this is the point that the CZ customer service rep was making: if you don't have the slide on the frame, the full safety mechanism isn't in place.
 

[inferno451]

Walt,

I agree with your analysis of the system. The CZ rep is also correct in that there are safety mechanisms in the frame (i.e. the trigger safety and drop safety), but I am addressing only the firing pin safety, not the safety of the firearm as a whole. This safety system is comprised solely of the firing pin block, its spring, and the triangular nub on the trigger bar.

You area also correct in that the striker spring would never be fully compressed with the trigger forward. The trigger safety and the drop safety are still completely functional, and do a fine job of keeping the P-10 series drop safe. I address these points in my conclusion section in my original post. Where the firing pin/striker block safety come into play is in the case of freak parts breakage or other mechanical disengagement. The trigger bar does keep the striker from moving forward, but what if for example the hook on the striker breaks off? Even in that case, since the striker isn't fully drawn back, it PROBABLY wouldn't matter. The entire firing pin safety could be deleted entirely from the design (and probably most modern designs) and it would probably be statistically just as safe. Let's say 99.998% vs 99.999% safe.

Regardless of the real-world statistical importance of the safety I think the point still stands that:
1-CZ found this safety system important enough to include on the design of this pistol.
2- Unless I'm missing something, the system appears to be entirely ineffective.

[JonNC]

Walt,

I agree with your analysis of the system. The CZ rep is also correct in that there are safety mechanisms in the frame (i.e. the trigger safety and drop safety), but I am addressing only the firing pin safety, not the safety of the firearm as a whole. This safety system is comprised solely of the firing pin block, its spring, and the triangular nub on the trigger bar.

You area also correct in that the striker spring would never be fully compressed with the trigger forward. The trigger safety and the drop safety are still completely functional, and do a fine job of keeping the P-10 series drop safe. I address these points in my conclusion section in my original post. Where the firing pin/striker block safety come into play is in the case of freak parts breakage or other mechanical disengagement. The trigger bar does keep the striker from moving forward, but what if for example the hook on the striker breaks off? Even in that case, since the striker isn't fully drawn back, it PROBABLY wouldn't matter. The entire firing pin safety could be deleted entirely from the design (and probably most modern designs) and it would probably be statistically just as safe. Let's say 99.998% vs 99.999% safe.

Regardless of the real-world statistical importance of the safety I think the point still stands that:
1-CZ found this safety system important enough to include on the design of this pistol.
2- Unless I'm missing something, the system appears to be entirely ineffective.

RE 1: I think CZ's (and practically every other gun manufacturer's) lawyers had more to do with the inclusion of the striker safety than the engineers/designers.
RE 2: It may be, but I don't see a way that the inclusion of the system can cause harm.

The only way I can see it being an issue, is if the following occurs:

Somehow the striker is pulled back under near-full spring tension
The "sear" on the back of the trigger bar vanishes or the disconnector or it's spring fails allowing the striker to be released and then the striker safety fails resulting in a discharge.

It's so remote of a possibility that it's not even worth considering, imho, although I do applaud your thoroughness and dedication to the issue.
I would much rather us as a community determine that this is much ado about nothing than for it to fly under the radar and eventually result in irreparable damage to someone or their property.

[inferno451]

Jon,

I agree 100%. The chance of this causing an ND and hurting someone is incredibly small. I just thought this was something that people needed to be aware of on a firearm that many are purchasing for carry and self defense. I know of at least a few people that have removed this firearm from consideration for carry (especially AIWB) due to these results.

[Walt Sherrill]

I agree with your analysis of the system. The CZ rep is also correct in that there are safety mechanisms in the frame (i.e. the trigger safety and drop safety), but I am addressing only the firing pin safety, not the safety of the firearm as a whole. This safety system is comprised solely of the firing pin block, its spring, and the triangular nub on the trigger bar.

Drop safety seems to be the biggest concern of most gun makers, along with an internal safety mechanism in the assembled weapon that only allows it to be fired when the trigger is pulled fully to the rear.   Unless the trigger is pulled (bypassing the trigger/firing pin safety), a heavy blow against the hammer or the rear of the slide won't cause an unwanted discharge.   

I know of at least a few people that have removed this firearm from consideration for carry (especially AIWB) due to these results.

Unless they think they have a need to drop an assembled slide and barrel with a chambered round from a great height onto a hard surface in such a way that the full force of the drop is applied to the end of a flush-hitting barrel, an additional striker safety mechanism would likely prevent an accidental discharge in that scenario.  But such a event would have to be intentional, not accidental or unintended.  Why anyone would want to do that is beyond me.   

Even California, in it's very arduous safety testing, doesn't go to that extreme.

[inferno451]

As far as I understand, the striker block safety is more to prevent travel of the striker under breakage than anything. If you imagine the tip of the striker hook breaking off, there's nothing the trigger and drop safeties can do to stop it from going forward. This isn't an unknown failure, it was apparently fairly common on the earlier M&Ps - https://mp-pistol.com/autoloaders/39316-m-p-failure-striker-breakage.html

[dwhitehorne]

Every striker safety/firing pin safety consists of the firing pin block, spring and trigger bar nub. CZ is just different in rotating the safety lever instead of a plunger system. HK’s VP9/40 went a different route also rotating the safety a different way from CZ.

HB Industries has a drop safety video with their trigger installed in the P10C.

My take is CZ employs multiple engineers that know more that we do about the design of their pistol. We should spend more time shooting and less time speculating on the internet. David

[Earl Keese]

There may be something to this, maybe not. I will say though, it seems like once every few months a first time poster shows up and claims that the P10 isn't safe, etc. This isn't the first time, and I bet it won't be the last. The internet is chock full of experts making videos.

[SI VIS PACEM PARRABELLUM]

There may be something to this, maybe not. I will say though, it seems like once every few months a first time poster shows up and claims that the P10 isn't safe, etc. This isn't the first time, and I bet it won't be the last. The internet is chock full of experts making videos.

Yeah ho hum we've seen this movie before. More glock guys claiming the CZ isn't safe. The gun when properly assembled is as safe as ANY other striker fired pistol out there and I can't say I've heard of a case of CZ leg yet.

[0119]

For a moment I thought I was on the FN forum. Even Walt's here! Where do these internet engineers come from?  If it's not bashing one manufacturer it's bashing another. Even videos and statistics to prove a non existent problem with flair, panache and fear mongering.  No matter who does it, no matter which brand they attack, there seems to be one constant. It is an effort to make a certain brand shine. One which is stuck in 1987.