.

If you would like to read the FBI's P320 report, it is posted at this address:

https://drive.google.com/file/...nel3bsDnM/view?pli=1

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Everything I see so far points to the previously reported issue where pressing the sear down causes the trigger to move back.

I just verified this on a P320 FCU I have in an AXG module. Pressing the sear down will cause the FPS lever to rise and the trigger to move rearward.

The FBI test showed that moving the slide around relative to the frame can cause the sear to release the striker. I would suspect that repeated movement of the slide is progressively forcing the sear downward.

This is sort of the tail wagging the dog. I agree that manually pressing the sear down all the way should not cause the FPS lever to rise or the trigger to move. The P365 works in this manner and we have no significant reports of uncommanded firing on P365's.

According to the previous video, modifying the P320 sear to remove the rear leg eliminates the sympathetic movement of the trigger and FPS lever when the sear is pressed down. Seems this might be the "fix", although I would also change the FPS lever spring so that it is captured at both top and bottom and preferably changed to a captured coil spring instead of a hairpin. Of course, the rear sear leg was put there for a reason so we need to understand why Sig designed it that way and if they can redesign it to eliminate the sympathetic movement.

The M18 in question had rough looking parts that were likely out of spec. Tolerance stack up between the FCU and slide, and the degree of looseness in the fit is also a factor.

AND I just confirmed on an M17 the same thing can occur even with the safety engaged. Damn.

So now we have a plausible answer. Most P320's may be OK, but SOME may have a combination of parts quality and tolerance stackup that creates the problem. I'm going to assume that "as designed" with all parts in tolerance - or more accurately all parts within statistical tolerance of a capable process - the defect cannot occur. But throw in enough variation and you may get a few bad ones.

Sig is in major trouble now and I can see the P320 justifiably being banned from all LE agencies. Military is probably in too deep to change at this point, so a fix is going to be needed. I do think it is fixable though - but Sig needs to own up and make the updated parts and get them fitted at no expense to owners.

I am pretty heavily invested in the platform after getting my first M17 Bravo (early black version) in 2018. I purposefully waited several years until buying a P320, and then made sure I only bought post-upgrade ones. I have several (6 I think), along with Custom Works FCU's, aftermarket parts, optics, etc. I even have a P320 mag CMMG Banshee and considered getting a B&T APC9KPro with a P320 mag lower.

quote:

The FBI test showed that moving the slide around relative to the frame can cause the sear to release the striker.

Only with the trigger partially pressed.

As to the trigger moving if the sear is poked with a stick, are the sear and trigger not connected? You pull the trigger, the sear moves. Wouldn’t moving the sear pull the trigger?

quote:

Q: What might the effect or phenomenon be called, of a handful of safety incidents with a product numbering, say, one million, the exact cause of which is unknown, and which causes many users of that product to want to abandon it, though it is overall a safe product to use?

A: The phenomenon you're describing could be referred to as "mass hysteria" or "panic amplification" in the context of product safety. More specifically, it might be classified as a "product safety scare" or "consumer panic response." These terms describe situations where a small number of incidents, often with unclear causes, lead to widespread fear, distrust, or rejection of a product despite its overall safety.This effect is often driven by:

Availability Heuristic: People overestimate the risk because vivid, widely publicized incidents (even if rare) dominate their perception.

Media Amplification: News outlets or social media exaggerate the incidents, increasing public fear.

Loss Aversion: Consumers prioritize avoiding potential harm over rational assessment of low risk.

Social Contagion: Fear spreads through social networks, leading to collective behavior like abandoning the product.

A related concept is the "nocebo effect", where negative expectations about a product lead to perceived harm or avoidance, even if the product is safe. In marketing or risk communication, this might also be studied under "risk perception" or "crisis communication failure", where poor messaging fails to reassure the public.

Grok 3 nailed it.

What will Grok 4 say?

This doesn't mean the problem with the P320 doesn't exist. It means only that individuals are highly unlikely to encounter the problem, despite the perception to the contrary.

I just seen a memo from ICE banning all P320’s from use.I don’t know if it was all of ICE or just certain entities inside of ICE.

Remington redesigned their M700 triggers based on less than this. Of course, the redesign had its own problems and they now use Timney.


I've got 3 320s. The only one I routinely carry in a holster is my X-Ten woods gun. Remote as the possibility might be, the idea of opening up my leg out on a hiking trail isn't all that appealing. I might need to take another look at the M&P 10mm until the issue is resolved. The Glock 20/21 grip is just too big for my hands.

quote:

Originally posted by Lefty Sig:
Everything I see so far points to the previously reported issue where pressing the sear down causes the trigger to move back.

I just verified this on a P320 FCU I have in an AXG module. Pressing the sear down will cause the FPS lever to rise and the trigger to move rearward.

The reason this happens is because the rear sear leg, which engages the trigger bar when the sear is depressed, which in turn engages the "captured safety lever" who's legs ride over it. According to Robert Burke (video posted somewhere a few weeks back in this thread), that rear sear leg exists as a function of the inertial drop safety that was added as part of the voluntary upgrade. By bottoming out against the trigger bar, it increases the inertial force necessary to drop the sear if the gun hits the ground.

According to Burke, the timing of this system is such that even if the safety lever gets actuated, it would not be fast enough to disengage the striker safety block before the sear drops, at least not under real world conditions. I would imagine that his comments are conditional on all of those parts being in-spec, though.

I wonder if a potential fix could be removing that rear sear leg and adding a tabbed trigger, which would replace the drop safety function of the removed sear leg, while at the same time adding a degree of protection from unintended trigger incursion. This would be a pretty simple and relatively inexpensive fix as triggers and sears could be replaced at the armorer level.

Obviously, that's just me thinking out loud, and I don't claim to be an engineer or a gunsmith. There may be good reasons why this wouldn't work, but based on my current understanding of the design it makes sense to me.

quote:

Originally posted by parabellum:
This doesn't mean the problem with the P320 doesn't exist. It means only that individuals are highly unlikely to encounter the problem, despite the perception to the contrary.

Bingo.

Glock had problems in the now distant past, that no one cares about. Glock didn't have to solve it in the internet age.

Every time someone makes a firearm idiot proof, they build a better idiot.

I have four 320s. One is a range-only gun and three are house guns, kept loaded in locked drawer-safes in various rooms of the house. I have no intention of carrying any of them -- I have 365s and mouse guns for that -- but I would still send them in for the "fix" if and when one becomes available.

quote:

Originally posted by trapper189:

quote:

The FBI test showed that moving the slide around relative to the frame can cause the sear to release the striker.

Only with the trigger partially pressed.

As to the trigger moving if the sear is poked with a stick, are the sear and trigger not connected? You pull the trigger, the sear moves. Wouldn’t moving the sear pull the trigger?

The guy in the video partially pulled the trigger, the FBI report does not indicate this. The part about "the sear manually released from the primary notch" is a bit unclear if they just wiggled the slide and frame enough to make it release, or pushed on it with a punch. The second test of another brand-new unfired M18 had the same results. So the FPS lever CAN fail to stop the striker when the sear is released without pulling the trigger. And that is probably due to the sympathetic motion I referred to.

And no, moving the sear on most guns does not sympathetically move the FPS lever and trigger. P365, Glock, HK VP9 don't - I just checked. I know Walther PPQ's and PDP's don't.

From the FBI report:

Because of the inherent movement between the slide and frame, a third test of the striker
safety lock was conducted. Approximately 50 attempts were made to determine if the striker
would impact the primed case after manipulating the weapon while holstered. The weapon
was pressed together and pulled apart (at the slide and frame). Thereafter, pressure was
applied to the frame and the sear manually released from the primary notch. The intent of the
manipulation and pressure was to mimic what might occur to a holstered weapon during an
officer’s duties, such as running, jumping, climbing, fighting, pressing a weapon against a wall
or vehicle, or obtaining a master grip on the pistol prior to drawing, etc.

BRF staff observed the primed case fired on nine attempts with the primer indent measuring
between 0.019”-0.026” with an average of 0.023”. While staging one attempt to allow another
BRF staff member to observe the striker safety lock function as designed, the weapon was
prepared and placed into the holster with no manipulation. A second staff member released
the primary sear notch from the striker and the primed case fired indicating failure of the striker
safety lock. The primer indention measured 0.018”.

BRF observed six instances where the primer did not fire but a small indentation was present
indicating the striker had contacted the primer. These indentations measured between
0.0005”-0.001”.

The remaining attempts resulted in no firing of the primed case and no evidence that the
striker had contacted the primer. Ultimately, in these instances the striker safety lock
functioned as designed.

A brand-new unfired Sig Sauer M18 pistol33 was obtained from MSP to determine if the test
could be repeated on another weapon. On the first attempt, the striker safety lock
successfully prevented the striker from impacting the primed case. However, on the second
attempt the primed case fired, indicating the striker safety lock failed to stop the striker’s
forward movement. The primer indent measured 0.023”.

quote:

The guy in the video partially pulled the trigger, the FBI report does not indicate this.

Pg 18:
“Additionally, during dry-fire manipulation it was observed the trigger could be partially pressed to the rear and the slide manipulated by hand causing the striker to fall completely. This was then tested using a primed case and the striker did in fact fire the primed case, indicating the striker safety lock was disabled based on the partial trigger press.”

That’s the only way in the FBI testing the FBI was able to get the striker to disengage the sear without poking the sear with a stick.

quote:

And no, moving the sear on most guns does not sympathetically move the FPS lever and trigger. P365, Glock, HK VP9 don't - I just checked. I know Walther PPQ's and PDP's don't.

Thank you, I have no way of checking this. I really like my PPQ 45.

Poking the sear with a stick will not cause the FPS lever/plunger to disengage on any of the other handguns I mentioned. That is the point. The FBI has shown that failure of the sear to hold the striker can result in a discharge. I know of no other pistol where this is the case, but I can check all the ones I own.

I don't buy the "partial trigger press" bit - it's too each to pull it all the way during testing.

Almost every Glock and similar designed pistol where the movement of the trigger bar causes a tab to slide across the FPS plunger, pushing it up and out of the way, disengages the FPS during take-up to the "wall". Even guns with levers that lift the FPS usually do their work during take-up and not during the final let-off.

I have been a big fan of the P320 platform since 2018 and have been skeptical of all of these AD claims until now. I have at least 6 factory P320's, and a modular set of 3 FCU's and various grip frames and slides, covering all configurations available. I also have a P320 mag CMMG Banshee. I'd say that's close to $10K in the platform. So I am not happy about all this either.

The way these things go, P320 will likely be deemed unsafe by every LE agency in the country. Why? Because ignoring what the FBI said opens them up to LIABILITY. We are enthusiasts, but there is no reason to stick with a platform amid all this "noise" when other perfectly acceptable platforms are available - notably Glock.

Sig needs to admit there is a problem that needs to be fixed and FIX IT. No more "voluntary upgrades". A FULL RECALL and retrofit of whatever is needed to solve the problem. Anything less and they will have zero credibility.

If ATF acted like NHTSA there would be a mandatory recall with a "stop use" until retrofitted.

quote:

Originally posted by Lefty Sig:
"From the FBI report: ...
"...the sear manually released from the primary notch."

Spurious or contrived test?

After all this, I still don't know if carrying my P320 is safe. I purchased it for the factory red dot due to aging eyes, even though strikers make me a tad uneasy during holstering. Being able to rail mount a light was a factor, too.

I've always felt 100% safe with my DA/SA P229. But no way to mount an optic or light on this 2002 vintage pistol.

Frustrating.

You can get a Legion P229 DA/SA with an optic cut.

quote:

Originally posted by Lefty Sig:
You can get a Legion P229 DA/SA with an optic cut.

Or just buy the cut slide.

Viewed in the light of all that has happened in the last few days, SIG's "It ends today" is utter, complete hubris.

This FBI report was from last year and SIG was invited but chose not to participate. The FBI was able to disable the striker safety lock by jiggling the gun around in the holster. SIG had time and opportunity to get ahead of this.

“It ends today” is going to be a case study in a textbook.

Here is the YT video clip of the latest 320 incident that was linked on page 24. An officer from the Ceres PD bumps her holster with her backpack, 320 fires. Watch the bystander's reaction for the precise moment of gunshot.