If every degree on the X, Y, and Z axes is a data point, there are over 46 million potential orientations in which to drop a firearm. Unfortunately, the SIG SAUER P320 has shown an unacceptably high potential for firing when dropped on a hard surface in at least one general orientation: on the back edge of its slide. SIG refers to this as a “negative 30 degree angle” and agrees that the P320 has shown a specific vulnerability to it. Below, we’ll answer why this is the case and present SIG’s solution.

The Physics:

Objects have mass, and mass has inertia. That’s an object’s propensity to fight acceleration (any change in velocity). An object in motion wants to stay in motion. An object at rest wants to stay that way, too. A trigger is an object; an object with mass. And inertia.

If a gun is falling, so is its trigger. The slide comes to an abrupt stop when it impacts a hard object, but everything else in and on the gun wants to keep moving. All those parts are stopped by the parts they’re connected to which are stopped by the parts they’re connected to. On and on until the part in question is the slide hard against the solid object.

The trigger, however, is out there dangling in space. It’s designed to move independently. Unsurprisingly, when a gun is dropped and impacts an object at a certain orientation, the trigger’s inertia tries to keep it moving in the direction in which it has been intentionally designed to move. The specific amount of force exerted in that direction depends on a handful of variables such as the mass of the object, its velocity, and the duration of its acceleration when it impacts the solid object (how quickly it stops).

In the case of the P320, the trigger shoe has enough inertia that, when the P320 impacts a hard surface at a sufficient velocity and oriented in such a manner that the force is relatively in-line with the trigger pull direction, the trigger moves.

Sure, there is an impact velocity at which the trigger shoe’s inertia would overcome the entire 5.5 to 7.5 pound trigger pull weight and actually release the striker. But this is not what’s happening in the P320 drop test discharges that we’ve seen. Overcoming that amount of resistance over the full pull distance is a tall task, indeed.

The Problem

What’s happening in the P320 is a confluence of two separate occurrences:

•  The impact moves the trigger shoe rearwards through its pre-travel pivot. What may feel basically like slack or play in the trigger actually serves an important mechanical function: it moves the striker block safety out of the way. The trigger is telling the gun, “Okay, the trigger is being pulled on purpose, so clear the plunger out of the way of the striker so it’s free to travel far enough to impact the primer.”

•  The impact jars the internal components, tests the limits of the fit between chassis and slide, and the striker slips off the sear. Only because the striker plunger was also moved out of the way by the trigger’s limited-but-sufficient amount of travel does the striker fire forwards unimpeded and ignite the primer.

We know this happens, because in both TTAG’s and SIG SAUER’s testing there were drop test incidents in which the striker released from the sear, but the gun didn’t fire. In those cases, the trigger hadn’t moved far enough (or soon enough) to clear the striker block. High-speed video (and reasonable postulation) showed other instances where the trigger moved far enough to clear the striker block but the striker did not slip off of the sear, and therefore the P320 also did not fire.

Both occurrences must happen together, with the plunger moving out of the way before the striker attempts to move through that space, for the gun to discharge.

The Fix

As we posted earlier, SIG announced a voluntary upgrade program for P320 owners. The Army’s M17 pistols, which came out of the Modular Handgun System trials, already have these upgrades and SIG reiterated that they were always planning to roll them out in the commercial P320s soon as well.

While this may sound like marketing spin, SIG has a reputation for regularly releasing generational product improvements (often to the ire of customers when “version 2” upgrades are not backwards-compatible). They also have a culture of continuous improvement. They never actually said “kaizen,” but the Japanese influence we’ve seen in their production philosophy was very obvious.

Additionally, from a purely economical standpoint it’s typically more efficient to produce a single version of a product than multiple versions. As much parity as possible across commercial, military, law enforcement, and other P320 variants makes sense. If all of the chassis and fire control systems, etc., can be the same, that saves production costs and increases affordability.

Production on current P320 models has been halted. The upgrades made for the MHS version of the P320 (the M17) are coming soon to the commercial P320 via the voluntary upgrade program. Those upgrades include:

A reduced-mass trigger shoe. The current version, which may change slightly before hitting the commercial market, is skinnier and significantly more hollowed-out on the back side. It also has a hole in the top rear. Mass is reduced by 34%.

This is, by far, the most critical upgrade component as it relates to drop safety.

A reduced-mass striker (a 25% reduction) and sear (a 37% reduction).

A trigger disconnect safety, which disengages the trigger bar if the slide is out of battery. This lever is seen at the top left of the chassis in the photo above (looks not unlike a sock puppet).

The sear housing geometry has also been changed.

SIG can and will perform all of these upgrades on current P320s if the owner so chooses. No change to the firearm’s serial number is necessary.

The Why

Based on feedback from users, including LE/Mil, SIG sought to eliminate the “double click” feeling of the trigger pull. Changes to the striker, sear cage, and trigger were done to facilitate this.

Some contracts demanded a trigger disconnect that disengaged the trigger completely should the slide not be fully in battery. So a disconnect was added.

In SIG’s quest for continuous improvement, they also lightened components wherever possible.

The Result

SIG brought us into their testing facility today and demonstrated that three upgraded P320s were all functional and fired properly. They then proceeded to repeatedly drop each one onto concrete at that precise -30° problem angle from four feet. At least nine drops in, none had discharged. That’s saying something considering TTAG’s redneck test resulted in two discharges in three drops.

Additionally, SIG showed us high-speed footage of both the current commercial P320 version and the upgraded trigger version impacting the concrete. The difference was night and day. While significant trigger travel was clearly visible on the current model, nothing but a quiver was visible on the new version.

Furthermore, we dropped off our P320 — the one we had tested — for upgrade work. As soon as the final version of the upgraded trigger is ready, SIG will be installing it and the other upgrades in TTAG’s gun and shipping it back to us. You’d better believe it’s going to meet concrete as soon as it’s back in Austin.

On Monday we’ll find out the details of how SIG is going to handle this upgrade program and what the logistics will look like for current owners. Stay tuned.

## 128 Responses to The Mechanics Behind SIG P320 Drop Safety Failures

1. Dan says:

Sorry sig, but after the P290, Mosquito, the MCX (still waiting on that new bcg) and now P320, we’re done here. Thanks for playing.

• Doktor says:

Ditto dan.

Sorry SIG. your marketing hype and product proliferation billboarding your name on all things gun has sucked resources from your quality control department.

Glock or nothing. Period.

• Dan says:

That’s where I’m landing. Now where is my damn Glock AR?

• Norincojay says:

GLOCK is a solid firearm. But they make only one operating system if I’m correct. A tried and true one. Sig does innovation. When you design new things bugs will happen and sig is good at coming up with new designs. I’m not going to fault them for that.

• Nick D says:

Ya, because Glock has never had a recall ! Oh……wait…….ummmm…….

• J.M. says:

Typical Glock troll. How quickly you all forget the Gen4 issues Glock had when it was first introduced (and those sorry sacks of garbage at Glock never owned up to it being an actual problem). How about all the brass to face issues Glocks have? How about the fact that just last year they had to recall the G17M because slides were flying off the frames during dry-fire? Sorry, your Glock “perfection” ain’t even close.

• anonymoose says:

Oh, come now! We all know the G17G2, G19G2, G17G3, and G19G3 are the only true Glocks and are perfect and don’t need anything changed (except for sights, trigger, and springs, barrel, etc), and any other handgun is heresy! Glock fanbois are the new generation of semifudds, just like the old farts who cling to Ruger Blackhawks and overrated 1911s like Colt Series 80s and Kimbers. They’re just like the people (most of them long dead now) who swore by the SAA when modern double-action revolvers, 1911s, and Hi-Powers were available.

• ActionPhysicalMan says:

The Sig 320 isn’t drop safe so naturally you conclude that the Glock is the only good gun in the world. That is some Glock fan boy brilliance.

• James Earl Hoffa says:

I’m not a Glock Fanboy I own 5 Glock but I also own a few ruger’s 45 Smith & Wesson’s a few Colt I like all my firearms that’s what America is about huge selection you can pick what you want. However I won’t pick a firearm that isn’t drop safe in a handgun 99% of all rifles and shotguns are not drop safe but handguns especially defensive handguns that are going to be used as a military sidearm or a police Duty gun or a concealed weapon permit holders concealed carry gun yes those guns need to be drop safe. Anything else would be absolutely ridiculous. I’ve been carrying a gun now for over 30 years and I’ve even sat down at a public restroom and had my 1911 come out of my leather holster and slide underneath the divider into the next stall. I simply asked if the man could take his foot and Slide the weapon back across the floor to me LOL. What I’m getting at is crap happens and there’s no way for you to tell when or where that is going to happen where that gun could be dropped. I gunsmith at a shop that has arranged as well and I can’t tell you how many people I’ve seen drop firearms in there and the good thing about the Sig is it appears if you drop it it only shoots the person who dropped it because of the awkward angle it puts a bullet right back at you LOL.

• ActionPhysicalMan says:

Sorry James that wasn’t directed at you. It was directed at Doktor. I am a bit sleepy though, so maybe he was being sarcastic rather than saying something really dumb.

• James Earl Hoffa says:

No worries brother we’re just kicking it late night old school style LOL. What time zone are you in I’m on the East Coast so it’s pushing 1:30 ish. Us late night T taggers LOL

• Glock Schlock says:

If Glocks are so damn perfect, why are there 4 generations of them?

• James Earl Hoffa says:

They get more perfect every gen LOL. Still no still sights LOL.

• Look, I do NOT think Glocks are “perfect” or anything similar to that, but “perfect” in 1982 ain’t the same thing as “perfect” today. Think about a perfect early 80’s television or Ferrari or microwave or power drill or whatever. “Perfect” is a moving target and updating a product to keep up with that makes sense. Really, four generations in that amount of time with what are, in all honesty, extremely minor changes is pretty impressive. Your average blender has changed more in that time than a Glock 17 has.

• James Earl Hoffa says:

And Gaston also made the plastic for the blender LOL.

• Anon in CT says:

Can I offer you a Walther CCP or a Ruger Mk IV ?

• Dan says:

Thanks but I’m going to stick with the house that Gaston built.

• C4v3man says:

House that Gaston built? Surely you don’t believe that Gaston invented or brought to market the first polymer framed high capacity striker fired pistol? Glock is hardly perfection, even the gen4 had it’s share of issues when it first came out. That being said, sig does have a high amount of models coming out that REQUIRE continual product improvements that other vendors seem to not have as frequently.

• James Earl Hoffa says:

The first polymer pistol would have to be the H&K I can’t remember the model number but it flopped it was released I want to say in the late 70s early 80s and it did not do well at all they’re collectors items nowadays. The thing that made Gaston Glock so different is he was the Tupperware man he didn’t have any rules to go by when he was designing his pistol he had some help from reputable gun manufacturers but he was brilliant in the fact that he had such a very very good marketing design and implementation. If I was ever running for public office LOL I would want his marketing team to push my campaign. You have to remember H&K was the first one to the table with a polymer framed pistol and it flopped when Glock came out in 83 he marketed the hell out of that pistol design and it’s been history ever since. Good pistol great marketing campaign.

• anonymoose says:

Does that house have plastic curtain rods?

• James Earl Hoffa says:

Plastic on the couches to everything’s Tupperware. LOL when you sit on the couches it sounds like you’re crushing up a Publix plastic bag. Plastic Fantastic. I’ve got like 10 polymer framed guns some Smith and Wesson some Glock and I wonder how the polymer is going to hold up saying a hundred years I wonder if they’ll hold together. I’m guessing they probably will seeing how my 83 Glock 17 Gen 1 still shoots after well over 30,000 rounds through it to barrels 5 recoil spring assemblies in 45 magazines actually wore the magazines out LOL. But I still shoot my 1911 much better that grip angle gets me everytime I shoot my M&P and my 1911 then I go to my glock and I can’t hit the broadside of a barn for about the first magazine until I get used to that goofy-ass grip angle LOL.

• Hank says:

I know we keep getting told no other striker fired gun has this problem, but I don’t care. I really want to see this test done on other striker fired… hell, let’s do SA/DA, 1911, and revolvers too. Everyone thought the initial SIG rumor was probably BS, but it turned out to be true. Now I want to see all the other popular hand guns exposed, because all the “experts” and previous testing could be innacurate as well. I personally have each type of handgun, and would like to be educated on the matter. Come on TTAG, think of the clicks and revenue you could make if you found ANOTHER popular gun that had similar issues!

• Does any body think there will be a recall? I know Sig did something when they had a problem with one of their AR guns fairly recently. I have only been shooting for 4 years-I am the new kid on the block and am not aware of the past, and history (ways of resolutions). We all know about the automotive industry history, With reference to guns what have other manufactures problems, and if that is the case what has have done in the past-if anything, when it comes to this type of wide spread possible problems in the future. I feel it is Sigs expense. It sounds to me (I am no lawyer) that if Sig does nothing it could be lawsuit central. Please, if you have a crystal ball or anything that might help. Give me an idea of what an experienced person can expect from Sig. I want mine fixed if there is a problem. I recently bought a NIB Sig p320 compact. The first time I shot it I had nothing but failure to eject etc. This gun was a lemmon. I called Sig, they told me they fixed the extractor problem and it would be one in a thousand that is the problem. I sent it to Sig on their dime (ed9Ex) pricy right there. They fixed it and it was the extractor ans spring. I have not had one problem since I got it back. 100% perfect. That cost them \$200.00 + in shipping (I asked The people at Fedex) what the cost would be as after it was fixed it had to be sent to my house w/adult signature. Plus the techs time etc. That is one gun 2 small parts= \$250-300.00. I would be cheaper to give us all new ones. I could go for that.

• Jeff says:

I suspect many P320 owners are going to be happy to get a free “Gen 3” XM## class trigger group upgrade that undoubtedly will not only pass the U.S. safety standards but exceed them.

Nearly every major manufacturer (incl Glock) has had models and versions with safety issues that required recalls/upgrades.

Once provided with adequate information (vs rumors) within days Sig figured out what the problem was and moving to make it right. The best part of the XM17/18 program is the extra testing being done on this platform means a good handgun is evolving into a great handgun. The military testing and evaluation of this handgun will be the best thing that ever happened to it.

• cmac890 says:

Yeah, I’ve been floating the idea of getting one of these for a while now, and I have to say, Sig appears to have handled this in textbook fashion. I’m not deterred at all. Although I might hold off for the upgraded models, I wouldnt turn my nose up at a really cheap current one.

• My first handgun was a Mosquito, my second one, a Walther CCP. I think I’m batting a zero. What’s next?

• Eric_CA says:

Funny, LOL.

• James Earl Hoffa says:

Try a Smith & Wesson M&P series pistol that fits your hand. Or maybe even a Glock now that this new 5th gen is coming out. My advice is try to find a friend that has multiple Brands and calibers and go with him or her to the range and try a bunch of different pistols see what you like and don’t like and limit it down from there. Sorry about your luck with your first two purchases.

2. TACTICOOL says:

SIG best years are long gone. Welcome to the crappy world of SIGARMS!

3. Shootespeare says:

As long as it doesn’t cost me a dime, sounds good. I can be patient. I think. Now where’s my CZ’s…?

4. Vhyrus says:

I am okay with this. Sig found a problem and they are fixing it along with adding improvements for free.

• Dan says:

My problem isnt with the issue or how it is handled as much as it is the repeated qc cockups and slow time to get fixes out in market. Still waiting on bcg for mcx recall three months later and I waited six months to send it in hopes that I wouldn’t be stuck in line.

• Vhyrus says:

Sig rifles suck. This is known. You buy anything that isn’t a bog standard AR and thats your ass buddy.

• James Earl Hoffa says:

Yeah I love the MCX especially how they decided in their infinite wisdom to use two small Springs as their recoil dampening system. There was a reason why Eugene Stoner used a huge recoil spring and buffer. The reason is if you drop a rifle in the water and get sand in mud in it you do not want small Springs they fill up with mud and cease to function. I saw a torture test done of the MCX and the guy was putting it in water and shooting it and then he threw it in the water and pulled it across the bottom pulled it up shot it three times and the bolt jammed to the back of the rifle and he couldn’t get it to come forward even by slamming the stock against the ground which would normally clear an AR-15 that bolt carrier group has become hung up. He takes the gun apart and the two Springs that run off of the bolt carrier look like a bird’s nest in a fishing reel that a three-year-old through. LOL it was a mess that whole system was not designed for heavy junk getting into the action if anything even small particulate get into the captured springs on the recoil system forget about it that rifle willimatic.

• Mausschubser says:

@James Earl Hoffa
As you mentioned Eugene Stoner. He did exactly that and put two recoil springs in a gun with the AR-18. The SIG rifle is a crossbreed between AR-1 and AR-18.

• Hank says:

Yeah. I was throwing around getting a 320, and I still probably will one day. But definitely going to wait for the current iteration to cycle out first.

• No one of consequence says:

One reason I’ve held off is, apparently, the .45 ACP version doesn’t interchange with the rest of the line.

Nothing with this it’s-not-a-recall-recall is going to change that, I think.

• mh46 says:

I had bad luck with a SIG P250 in 9mm. Kept getting miss-feeds and stovepipes. I tried several different brands of ammo, they all did it. When I feel the need for another SIG it will not be a striker-fired model. I’m happy with my P6/P225 and P245.

• James Earl Hoffa says:

Sig Sauer used to be a good company before they got cheap as hell on their materials quality control and actual design work in this is not just one problem but two problems are going on simultaneously in this firearm. In the article above it clearly states that the trigger is moving back a very small amount only far enough to let the firing pin safety plunger be depressed the second problem is that the frame is flexing under the slide due to the impact force and causing the Seer to let go of the striker and because the firing pin block safety was removed by the slight backward travel of the trigger you have a kaboom and a bullet comes out this is a turd pistol same with the P250 and all cigs that were made after 1989. They’re living off of their name and putting garbage in the hands of people as their test guinea pigs. Bad way to be a Firearms manufacturer and even worse to be a military contractor that is developing the next sidearm for the United States Army give me a break if I was the Army I would send that junk right back and go with a company that builds quality products whether it be Glock Smith & Wesson or whoever doesn’t matter to me but I damn sure don’t want to pistol that if I drop it on a concrete floor it could kill me or family member that is just unexcusable garbage.

• Jeremy S. says:

It is not clear to me exactly by what mechanism the striker slips off the sear, though this obviously is happening upon impact some of the time. It may have nothing to do with the frame…might just be the shock causing the sear to slide down or the striker to move up or whatever potential combination of factors that cause those two parts to move away from each other and release. All we really know there is that an impact can cause the striker to release, and if the impact also caused the striker block safety to be cleared out of the way, then it’ll fire.

• James Earl Hoffa says:

Exactly, there’s some people on here though that apparently didn’t read the whole article and they think that it falling on its back is causing the trigger to completely make the weapon fire as if you were pulling the trigger when in fact it’s a two-part problem. But I agree with you 100%.

5. James Earl Hoffa says:

Does anyone think that this could be caused by the stainless steel frame that cerealized not being completely encassed by the polymer body like Glocks and M&P semi-auto pistols are??

• A GLOCK won’t do exactly this, as the striker is only like half-cocked so if it were to accidentally fall, it wouldn’t have enough power to ignite the primer anyway. Of course, you pay for that by having to cock the striker the rest of the way with the trigger pull, which makes it longer and typically heavier. If you want a short, crisp trigger pull then the striker (or hammer) needs to be pre-cocked or close to it. Many striker-fired guns operate that way, and many don’t. They vary from 0% pre-cocked to 100% pre-cocked. The P320 is apparently something like 90%.

• James Earl Hoffa says:

Thanks but I thought they said the frame was flexing as well causing the Seer to come off the striker and letting it go forward I’m pretty sure that’s what they said. So if the frame wouldn’t Flex because it was surrounded and encased by polymer would solve the problem but literally defeat the purpose of being able to change out grip frames.

• They did not say that. I said that. There is play between slide and frame on all guns. Most polymer frame guns with small little slide rails front and rear have a decent amount of play. Glock for sure, and the vast majority of others. Usually these guns have more play there than metal-framed pistols with longer rails. I don’t think anything is unique in this regard with the P320. Also, the crisper you want the trigger to be the less overlap between sear and firing pin there has to be…

• bluegator3 says:

A Springfield XDM 40 Caliber Pistol. Has a handle Safety on it!!! If you don’t have your hand griped on the gun it won’t fire or shoot!!!

• BoomChuckalucka says:

That’s why they’re redesigning the fire control group. Making it lighter in mass. The part you said went Cuckoo for Cocoa Puffs. (cerealized)

6. Ed says:

“SIG reiterated that they were always planning to roll them out in the commercial P320s soon as well.”
So, they WERE beta testing on their customers again….at least H&K gets it right before they overcharge us!
Had a P938, was not reliable, sold it. All the 226 variants are truly right handed and suck for lefties. Almost bought a mpx, got a CZ instead…mags are WAY cheaper. My old lady has a P238, she likes it…bit I don’t see any other Sigs making their way into this house anytime soon.

• Jay in Florida says:

Your welcome. As an owner of an early model of the P238. I was as they say a “Beta Tester”. My gun had over 12K rounds through it in the 1st year of ownership back in 09. Every part short of the frame had been replaced in 4 trips back to Sig CS in the 1st 18 months. Some parts replaced and “newly upgraded” 3 times. The gun has sat in my safe unfired since its last return 6 years ago. I wont sell or trade it and stick some one else with a faulty firearm. Nor will Sig replace it as they should have back in 09. I waited almost 4 years after its release before buying a P938. It wasn’t a vast improvement. I will admit mine does work but…………..
Sig wont ever see another nickel of mine and I don’t care if they do come out with the next best gun ever made. It wont be in my holster.

7. Hannibal says:

It sounds like they are serious about the problem

… but I still can’t understand how this gets out of the factory with such a fault. Yes, it might not get caught on the specified government test, but that’s the lowest regulatory bar- I would hope they would put more effort in.

• mer says:

It’s a function of numbers. As pointed out in the article, take the orientation of the pistol to be in 3 dimensions. Each of those dimensions has 360 degrees of freedom. 360*360*360 is 46,666,000 combinations. Add in the distance dropped and to test completely becomes a heck of a long time. Article states “…dropped from 4 feet” and it didn’t fire. Should they have dropped it from 5ft? 6ft? 20ft? Anything mechanical can be made to fail, but if it fails only under an absolutely unreasonable set of conditions, does it matter? Lets say the modified pistols still fire when dropped at that precise angle but only starting at 20 ft. Is that a normal set of conditions? Only if you’re a painter, roofer or skyscraper iron worker.

All testing of pretty much anything is done to some percentage of “nominal” conditions (hence the standardized tests). If someone mandated “complete testing of all possibilities” nothing would ever get released to the public (not just firearms, you couldn’t even get coffee makers to market).

• DonS says:

As pointed out in the article, take the orientation of the pistol to be in 3 dimensions. Each of those dimensions has 360 degrees of freedom. 360*360*360 is 46,666,000 combinations.

As pointed out elsewhere in these comments, the article is wrong.

First, rotating about the Z axis (i.e. in the direction of travel) is irrelevant and unnecessary. If I’m holding the pistol so that the barrel is horizontal and the grip is perpendicular to the ground (i.e. in a “normal firing position”), it doesn’t matter if I’m pointing the gun north, south, northeast, or in any other direction on the compass.

Second, one of the other axes only has 180 degrees of important info. As also pointed out elsewhere, we can visualize “drop orientation” as if the pistol was inside a transparent globe (think “Earth”). Any drop orientation can be represented by 360° of longitude and 180° of latitude.

So, if we’re testing in increments of 1°, we only have 360 x 180 == 64,800 combinations.

If we test at 4 different heights, we still only have 259,200 combinations.

Of course, those 259,200 drops can take a while, if we’re inspecting the primer for damage after each drop and periodically inspecting the firearm to ensure it hasn’t suffered damage that might keep it from firing at all.

All testing of pretty much anything is done to some percentage of “nominal” conditions (hence the standardized tests). If someone mandated “complete testing of all possibilities” nothing would ever get released to the public

Well, yeah, because there are an infinite number of possibilities.

The “standardized tests” (e.g. NIJ, SAAMI, California) only specify 6 orientations and 1 drop height. Even when inspecting/replacing the primer, cycling/resetting the gun, and inspecting the gun for damage after every drop, as well as repeating the tests across three samples of the gun, you can complete a standardized test in an afternoon. For California, you have 18 drops. If you spend 10 minutes disassembling, inspecting, reassembling, and test firing the gun after every drop, you’re done in 3 hours.

Interestingly, SIG hasn’t done the tests for California (or, at least, hasn’t paid that state to have the P320 “certified”). The P320 isn’t on California’s “Roster of Handguns Certified for Sale” and cannot be sold by dealers to normal citizens in that state.

• California’s microstamping law went into effect in 2013. NO new pistols have been added to the Roster since, as the specific technology required to meet their spec does not exist. SIG stated that the P320 absolutely passes CA DOJ drop testing, though I don’t recall if they had a third party verify or just did all the tests in-house. Which they can do, btw, in their test lab. They have all of the various impact surfaces and other testing specifications on-hand. SIG did show us the certificates/letters confirming the P320’s passing of a dozen or so drop tests by various government (both state and federal) agencies, law enforcement agencies, industry and safety/insurance orgs (SAAMI, ANSI, etc), militaries, etc…

The gun DID pass basically every safety test out there, most of which include drop testing.

• DonS says:

California’s microstamping law went into effect in 2013. NO new pistols have been added to the Roster since, as the specific technology required to meet their spec does not exist.

Yeah, I know. Used to live there. Couldn’t get new guns. I probably shouldn’t have mentioned the lack of P320 on the roster.

SIG stated that the P320 absolutely passes CA DOJ drop testing

And it almost certainly does, given CA’s standard.

though I don’t recall if they had a third party verify or just did all the tests in-house. Which they can do, btw, in their test lab. They have all of the various impact surfaces and other testing specifications on-hand.

Though they likely didn’t go through the CA-mandated process (since they couldn’t comply with CA’s microstamping requirement, anyway), CA would require them to go through a “DOJ-Certified Laboratory”. I don’t know if there’s anything prohibiting a manufacturer from also being a “laboratory”.

SIG did show us the certificates/letters confirming the P320’s passing of a dozen or so drop tests by various government (both state and federal) agencies, law enforcement agencies, industry and safety/insurance orgs (SAAMI, ANSI, etc), militaries, etc…
The gun DID pass basically every safety test out there, most of which include drop testing.

I have no doubt about that, given that the tests I’ve seen (NIJ, SAAMI, California) specify only 6 orientations – none of which are “negative 30 degrees so it impacts on the back end of the slide”.

It has not been my intent to slam SIG. They almost certainly passed every published test out there. But, it turns out that there are conditions where it can fail and, apparently, those conditions aren’t all that hard to reproduce (once you know about them, of course). It just so happens that those conditions aren’t specified in any of the standard drop tests.

• Desert Dave says:

Point taken, but, it would seem that there are a few key angles that would make the most sense to test. In particular any angle that the inertia of a fall and sudden stop could effect the firing mechanism in this way. You could cut down a few millions of those possibilities. Because that is the issue with this pistol, the angle of the dangle.

• Agreed. I mentioned this quite firmly in the meeting (sort of yelling at another gun writer who bought into it too much haha) in response to the assertion there were practically infinite ways in which to drop a gun, therefore they obviously hadn’t tested everything. Because, as you say, the engineers should be able to ID a couple of particularly vulnerable circumstances and have the lab test them and/or run them through finite element analysis programs.

The whole reason all these gov drop tests include dropping on the muzzle is because firing pins used to be free-floating as the norm. It was an obvious vulnerability that the inertia of the pin could ignite a primer upon a hard drop on the muzzle. There always exists, too, a possibility that a drop on the back of the gun causes the trigger’s inertia to effectively pull the trigger. We test for that.

But the standard, barrel pointing straight up orientation doesn’t align perfectly with the direction in which the P320’s trigger pivots and the polymer frame absorbs too much of the impact anyway. Aligning with the trigger travel direction means canting the gun rearwards, which also makes for a solid, metal-on-ground impact. This is the precise problem angle in this case. (advantage of hindsight here, yes)

Intuitive process should lead to “non-standard” drop test angles being recognized and tested. Look for vulnerability. Test it. Government testing protocol be damned.

I do think SIG will be on the forefront of this now, and they asserted as much.

8. Red in CO says:

Anyone else raise their eyebrows at that picture? I see at least two people in VERY close proximity to a firearm being drop-tested (and drop fired). Seems just a tad hazardous to me, but what do I know….

P.S. TTaG, I’m still having to fill out my info each time to comment….

Dude it was case’s with primers only, no bullet seated

• Hannibal says:

I can see why he’d be confused just looking at the photo. One wonders why someone would be wearing plate armor in such a situation. Soft kevlar would make more sense but if it’s just a primer a pair of goggles and gloves should be it (after checking carefully for barrel obstructions).

9. DJ says:

This must be how Robert felt about his Caracal. At least I can get it fixed.

10. James Ivy says:

If they were planning on making rolling changes to the design then they were very aware of this situation I believe and that I do not appreciate nor should uncle Sam or anyone for that matter this s**t is not a joke! Like my old 700 that put a turd in my pants and a hole in the ground (thankfully , 4 rules always!) A company who knows this has a moral obligation period!

11. Geoff PR says:

“Objects have mass, and mass has inertia.”

Mass in *motion* has inertia (potential for ‘work’), mass at (relative) rest has none.

Mass at rest fights velocity applied to it.

Big difference…

• I’m not sure about that… The word itself (root: inert) denotes objects at rest. But I’m a language guy, not a physics guy.

If inertia doesn’t properly apply to objects that have no momentum, what is the term that does?

• Negative. Sounds like you’re thinking of kinetic energy and/or momentum. Physics definition of inertia:

“A property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force.”

• mark_anthony_78 says:

Stationary objects have inertia too.

Think of the table cloth trick…

• Norincojay says:

Potential energy.

• No one of consequence says:

Mass in motion (relative to the local rest frame) has momentum, which is proportional to the mass’s velocity in the local frame.

In an inertial frame of reference, objects don’t change their velocity unless acted upon by a force. (In a non-inertial frame this doesn’t apply.)

Inertia, per see, refers to a type of mass (inertial mass) that we use when calculating, say, the force needed to give an object a given rate of acceleration. (In this universe, gravitational mass equals inertial mass for every form of matter we know about, but exactly why that should be, or whether it always has to be, is an open question.)

• Thankfully I live my life one inertial frame at a time, constantly in an inertial frame of reference and highly wary of those fools in a non-inertial local rest frame.

• No one of consequence says:

Of course, strictly speaking that would be all of us… 🙂

• James Earl Hoffa says:

Sig knew about this problem from the get-go. Don’t think for a second they didn’t. Just like Remington with the Remington 700 and the Walker trigger they knew that trigger wasn’t being installed and safety checked correctly and they took it to the attorneys and they figured out that one or two people shot per year with lawsuits was cheaper than recalling something like 700,000 rifles at the time. Sig was trying to avoid losing the Army contract and roll the dice that nobody would drop one at that goofy angle. I’ve personally seen clocks drop tested on the muzzle on the rear with SNAP caps inside and the hammer or the striker never dis lodges and falls same with Smith and Wesson they made extra sure that the weapon if knocked out of your holster being a police officer or knocked out of your hand during a struggle wouldn’t hit the ground and go off it’s common sense. Of course everybody’s going to say oh I just won’t drop the gun that’s like saying I’ll only carry a gun next Wednesday because I know I’m going to be robbed. That’s BS the gun should be drop safe any well manufactured name brand firearm that is designed to be carried as a duty weapon or a concealed carry weapon should be drop safe end of story.

12. Dan says:

Hey credit where due- this site has done a really good job on this story imho.

• Joel says:

Agreed. Objectively defensive of SIG and very proactive once the problem was personally verified.

13. Frank says:

So they only need the FCU/chassis to fix the issue? Or do they need the slide and barrel as well? Or the whole gun?

• Jeff says:

My guess (just a guess) is that they are going to:

1. Gut your current FCU frame and install the newest components from the current XM17/18 revision.
2. Looks like this will also include a new striker assembly.

So I’d expect to have to ship at least the FCU and slide to them.

I’m curious how they will handle things for those that have additional slides/calibers.

We’ll see for sure come Monday.

• James Earl Hoffa says:

Didn’t Sig Sauer also have like a 225 or another striker-fired smaller brother of this gun and it was called the P to something it wasn’t the 2:20 or the 2:26 or the 2:29 or 2:28 but there was a one that was a polymer frame that was a little smaller and named a different number anybody know if that one goes off when you drop it?

• Whole gun. Frame and slide require small modifications to fit and function with the new components (mainly, the trigger disconnect).

• Heathen says:

The Fire Control Unit is considered the frame on a P320,so the only things that should be needed to be sent in are the FCU & the slide.

We’ll know for certain Monday.

• No. The whole gun. The grip has to be modified to clear the disconnect. Not just the chassis, the actual plastic part you hold onto. The grip, chassis, AND slide must be modified. To avoid getting bogged down in further semantics: THEY NEED THE WHOLE GUN.

• Heathen says:

Well if that’s the case then my decision on the “upgrade” is becoming easier. I’ve several grip modules.

14. Tex300BLK says:

Fully cocked strikers sure are nice… until they aren’t.

15. JPD says:

This whole thing is a bag of nothing. I am 65. Been shooting since I received a single shot, bolt action .22 at the age of 5. I have NEVER had an OOPS! moment with a firearm. Why? My Marine grandfather, and two Marine uncles, plus my Air Force stepdad taught me how to respect and handle firearms.

One rule they hammered into me. When handling a firearm, NEVER allow yourself to be distracted, by ANYTHING!! (This should by rule #5).

I work as a range officer at my club. Countless times I see people walk up to a person, with a firearm in their and hands, and start a conversation. Eating, drinking, listening to music, having sex, and watching Oprah, while at the firing line.

So, yeah, I own a P320, my everyday carry. At some point, I will send it in. Am worried about dropping it? Not so much, you see, I was taught that their is NO firearm that is safe to drop, ever, in any situation, in your lifetime, and the next, period.

What did Gramps teach me??? John, are you going to place your life in the hands of the testing done by the government? Or some company engineers? Get a grip.

• Don says:

I am not afeard. If I decided I wanted a P320 this would not deter me at all.

• ai338 says:

Pistols have drop safeties for when the other safeties and the shooter all fail. It’s a last resort safety for a moment you can’t plan for. No one sets out to intentionally drop a loaded gun. As they say, Shit happens,and it’s there to cover your ass for a moment you can’t plan for. Thinking it will never happen to you because of your perfect gun handling skills makes you more dangerous, not less.

• Mike H. in WA says:

This, realistically isn’t going to be an issue for the majority of us private owners of the P320. However, Patrick R at The Firearm Blog was able to replicate the issue by striking the back of the slide with a rubber mallet. While most of folks won’t be striking the gun, a hard strike to the slide is a vey real possibility for LEO users (like during a struggle while arresting someone).

• Pseudo says:

Yeah, just saw this. I asked for him to jam the trigger forward and see if he can replicate it. That would be a direct test of the theory put forward in this article. It’s a reasonable explanation, but it’s also really easy to test so why not?

16. Kmeisner says:

Hey Jeremy, I love your writing and ever since that funny pocket dump of the day post I’ve been following you. Did you only test on concrete? What about wood floors or other surfaces for home carry? Are people really not willing to carry because of this one unlikely scenario? I understand the physics behind it, and always thought other guns with lighter triggers would be prone to this. How do other guns with lighter triggers differ from this gun’s ability to self ignite?

17. FedUp says:

Ah, I didn’t think of that.
So anything that uses the pretravel/takeup phase of trigger travel to release a firing pin block safety is susceptible to deactivating that safety in moments of extreme acceleration?
Makes perfect sense, but I never would have thought of it myself.

18. Flash Gordon says:

Was there any mention of those of us who have multiple slide assemblies from exchange kits?

19. Dang it, this makes two of my stable that require retrofitting!!! I’ve had my P320 for a couple of years. I’ve never dropped it but I have dropped other guns.

I still haven’t been sent a shipping label for my Ruger Mark IV…

20. Hoyden says:

So in 20 years will a non-upgraded 320 be worth more than one that’s had the upgrade(s)?

Ruger Blackhawk, Bearcat, Single Six not upgraded to “hammer the hammer”.

21. W says:

Did they ever do computer simulation of drops, so that they could avoid doing 46,000,000 real world drops? Such capabilities have existed for a very long time. Heck, when I was in the business over ten years ago, that stuff was commonplace. Or does Sig merely design and build to existing, known customer and industry specifications?

• They’re using FEA. I think, now, to a more extensive degree than before.

• W says:

Thank you for taking the time to answer my question.
Sincerely.

22. No one of consequence says:

So, to be that guy … There are actually only 360 x 180 impact orientations, at one degree each direction per, or 64,800. The other 180 degrees is the “back side” of the first 180, and the final 360 Jeremy included would just represent about the axis the impact happens along and wouldn’t change anything. (Think about putting the gun inside a globe, and you can point to any potential impact point using latitude and longitude.)

At one second per impact, 10 impacts per point at each of three different impact forces, it would take 22 1/2 days to test all possible impact orientations. Not at all infeasible with some automated test equipment. And for a major manufacturer it might not be a bad investment.

But other than that … Thanks for all the work on this. Much appreciated!

• DonS says:

To be that other guy…

It took me a few minutes, but I think your globe analogy works well. Presuming the gun is fixed inside an imaginary globe, with its center of mass at the center of the globe and its muzzle pointing at the intersection of equator and prime meridian, we can represent every possible drop orientation in terms of 180° of latitude and 360° of longitude by rotating the globe (and the gun within it), such that direction of travel during the drop is a vector from the center of the globe through those coordinates.

However…

Averaging 1 second per drop doesn’t seem likely, unless we have many samples being tested in parallel. Or some really impressive test fixtures.

1. We need to inspect the primer after each drop (or, at least, periodically) to ensure that it wasn’t damaged or deformed such that a “real strike” (maybe the very next drop) will fail to set it off.

2. We should probably cycle / reset the gun after each drop, to ensure that it hasn’t become “jammed” such that it won’t fire at all.

3. We need to periodically inspect the gun for any damage that might affect subsequent drops.

We can do #1 and #2 at the same time, but that would add a bit of time to every drop. #3 likely adds a few minutes, but we don’t have to do it for every drop (maybe every 1000).

Another problem is that if we’re really “dropping” the gun (i.e. letting it fall and depending on gravity to give it its impact velocity), we’re approaching 1 second per drop just in “falling time”. That is, if we dropped from 4 feet (0.5 seconds), 8 feet (0.71 seconds), and 16 feet (1 second), the average time just to fall is about 0.74 seconds per drop. That gives us about a quarter of a second to retrieve the gun from its [random] resting place, raise it to the next drop height, and orient it as desired.

I presume you’re thinking of some kind of test equipment that holds the gun in a certain position / orientation then “whacks” it with a hard, flat, massive object moving at a desired velocity, and which can whack the gun, reorient the gun, and reset the impactor in 1 second per cycle (on average). The problem with this is that we’re holding the gun – it’s not free to move when whacked. If it’s not free to move, it doesn’t accurately simulate a drop where one part stops moving and another (e.g. trigger components) continues due to inertia.

Finally, we should probably test more than just one sample of the gun through all lat/lon/velocity combinations.

23. J- says:

I am actually surprised by this. In the Glock the trigger and trigger bar both travel reward. In the SIG, the trigger pulls the trigger bar forward. If dropped on the rear, inertia pulls the trigger to the rear but it also pulls the trigger bar to the rear which resists the movement of the trigger. I would have figured that these forces would have canceled each other out, which is how they advertised the gun being drop safe without the tabbed trigger.

24. James Earl Hoffa says:

I’ve seen a lot of guys making statements that it’s just the trigger that is traveling backwards as the weapon is dropped at an awkward angle on its beavertail and the back of the slide. Clearly written in the problems section of this story they state that the frame and the slide are distorting and the Seer is Letting Go of the striker which is free to hit the primer due to the trigger coming slightly rearward from the impact as well this is a two-part problem this isn’t as simple as the trigger coming back that’s only half the story. The other problem is the body of the firearm is flexing because the polymer body and the stainless steel cage which is cerealized is not embedded into the polymer. Plus the fact that cig uses a striker that is set at 90% ready to go to improve the trigger Phil. It’s really a given take if you’re going to have the striker sit at such a ready to go position and you have a somewhat flimsy grip frame with a somewhat movable chassis sitting in it you’re asking for problems.

25. MG says:

The P320 has a really great trigger pull, probably the best striker fired pistol trigger I have fired. The system may not be perfect but it is a step in the right direction. I’m glad to see progress being made in the world of pistols, even if the P320 turns out to be a failure. I would love to see CZ come out with a modular pistol.

A lot of these Glock comments remind me of the old days when 1911s were considered the only viable option for a defensive pistol. Glock proved the 1911 club wrong and at some point someone is going to definitively out due Glock. Maybe that is why some Glock owners are so offended at the idea of anyone daring to innovate, just like all of those 1911 owners who hated the idea that a “plastic pistol” could outperform their version of perfection.

• James Earl Hoffa says:

I remember those days brother I had a 1911 and I had a Glock back in 1985 actually I got the 1911 and 75 and the Glock in 85. I think the point here is you can drop a 1911 s*** you can use a 1911 as a freaking Hammer same with a Blog and you’re not going to get a round to go off. Safe action on the Glock and thumb safety and grip safety on the 1911 along with a firing pin block on the model 80 series pistol. I’m all for innovation but I’m not going to drive a dragster without a roll cage in a helmet and a 4 point harness and I’m not going to own a firearm that if someone was to accidentally drop it or somehow get it out of my hands during a struggle worried about getting shot by my own gun with no one behind the trigger except for itself that goes against all handgun safety rules and Manufacturing standards in the United States for military and defensive combat pistols even civilian concealed carry pistols that’s a big no go you do not collect the prize directly to jail with your poorly executed design. They should have to put a fully loaded gun with one in the chamber in a dryer with a remote turn on switch and Tumble that son-of-a-gun for about an hour and see if it pops off around it’s going to hit on just about every surface possible and if it blows a hole in the dryer at a safe distance nobody gets hurt and you find out that your gun isn’t drop safe. LOL

26. James Earl Hoffa says:

• Jeff says:

There are more than a few folks in LE that only want to carry a Gen 3 Glock today. I would say most of the Gen4 teething issues and/or bad batches of components have been flushed out, but I’m not sure after what I saw with some G19s in a class this Spring.

Bottom line is we have several really nice handgun choices now, but none of them are perfect and new one’s will likely have bugs to be worked out. The Four Rules of gun safety exist for many reasons including the “we didn’t think or test for that scenario” moments when Uncle Murphy pays a visit.

27. John in TX (Was CT) says:

So… they didn’t show you that the fix worked on an existing, known-to-fire-when-dropped P320?

Maybe I’m paranoid, but I don’t think that they necessarily showed you that their fix for existing guns worked.

• There is no distinction between those things. The existing gun with the upgrades installed in place of the current components is the same thing as a gun built with the upgraded components to begin with. And, at any rate, they aren’t yet manufacturing the commercial frames and slides with the upgraded stuff already done, so these guns do actually fall into your first scenario (an existing gun receiving the upgrade).

28. Strongarm says:

Thanks for the physics input. However, as clearly seen in the photos, the trigger bar is mounted over the axis of the trigger and moves at the opposite direction. Further, seemingly, the masses of trigger bar and connected upper arm of trigger is bigger than the mass of downwardly panduling trigger finger arm.. This means, if a drop or impact occurs, the trigger and trigger bar would act in the opposite directions.

If so, how it can be possible to move the trigger through inertia in a muzzle up drop happens…The bigger mass of upper members of trigger and its bar should cause the lower member to stay motionless or very little action forward and this should be the cause of these units had not been obtained with a passive trigger safety lever.

But as can be seen in the slow motion videos, trigger acts rearward… This event can not be explained through simple inertia and mass correlations… Needs thinking further.

• You’re speculating on the mass of those parts and assuming they travel on the same plane as the trigger pivots on, and likely forgetting to factor in differing leverage due to each mass’ different distance from the pivot point (i.e. polar moment of inertia acting on the pivot).

Bottom line is that the results bear out the hypothesis: the trigger shoe with more mass travels from the impact and the trigger shoe with less mass does not. With nothing but that one change, the drop vulnerability seems to have been resolved and SIG said they did 2,200 drops over the weekend to confirm. It’s likely that the new setup meets your description of what you think should be the case, but the old setup did not.

• Strongarm says:

Dissapointed… Sorry… Writing in the medias open to public not only registers the intelligence but the ignorance as well. Be more carefull…Paymore attention.

29. Shire-man says:

I hope they’ll just send out parts or at least let me drop it off and pick it up in person. Eppings about an hour away. I hate shipping/receiving firearms. They never arrive when I’m home to sign.

• They’ll need the complete gun, as the slide and frame require modification to fit the new parts (mainly for the disconnect).

30. JPD says:

Here’s a clue for all the Glock fan boys. Check out the history lesson from Tamara Keel @ View from the Porch. She recounts the very similar recall, by Glock, in 1992 affecting up to 500,000 pistols. Yes, some of the same parts, in an “upgrade” by Glock. After reports from New York law enforcement of two unintentional discharges. Here is the link.

So, combine this with ALL the other firearm. auto, dishwasher manufacturers, (like Remington, etc) who have addressed problems with their products.

31. Accur81 says:

Well, kinda glad I don’t have an old 320, and won’t get one anytime soon. My 226, 227, and 229 have had zero issues. Looks like Sig is addressing the problem.

32. James Earl Hoffa says:

You guys are failing to realize that there are two problems going on simultaneously with this pistol number one when it’s dropped on its back on the beavertail and the slide the trigger only moves very little rearward. However it is enough to disengage the firing pin safety plunger which allows the firing pin and Striker assembly to move freely forward. The misfire is coming from this and the fact that the chassis is flexing allowing the Seer to disengage the striker which is already cocked at 90%. So when it disengages the Seer from the striker the firing pin safety block plunger is already disengage from the pistol falling backwards so the weapon fires its two problems going on simultaneously that causes this event not just the trigger moving backwards. Read the entire article please.

33. Seth says:

To all those hating/bashing SIG, how about redirecting your venom and energy at the US and military safety standards that these guns PASSED? How about demanding that the standards and testing methodology be changed?

34. Russ H. says:

Easy fixes: Don’t drop your P320, carry it on an empty chamber (LOL) and glad I didn’t buy one yet. I love Sig but this is pretty bad. And no, you won’t ever find a butt ugly Glock in my arsenal. Not yet at least. Maybe a G43 down the road… I just won’t be able to look at it or show it off to my buddies – the red headed step child.

35. TommyJay says:

For Jeremy S.

A couple questions: 1) So a “trigger shoe” is what everyone else (including Sig) calls a trigger bar? 2) J- says that the trigger bar moves forward when the trigger is pulled backward. Is this true? An exploded diagram of the fire control assembly seems to indicate this is true.

If 2) is true, it’s a big deal, and the article fails to explain how a trigger bar with 10 or 20 times the mass of the trigger lever can possibly move forward when the gun is dropped on the butt of the slide.

I have a guess. The last photo in the article shows a vertical plastic link connecting the trigger to the trigger bar. At the first moments of the impact, the trigger bar is trying moved rearward but the trigger comes up hard against the trigger stop pin, but… The inertia of the trigger bar is great enough to flex the plastic link as though it is a spring. And when the plastic spring snaps back, it launches the trigger bar forward, which then disables the firing pin block.

THIS is the essence of shock and vibration analysis. Nothing is perfectly rigid, and all of the non-rigid components can oscillate.

• Jeff says:

That is not plastic, it is metal.

• TommyJay — no to everything.

First, a “trigger shoe” is the part that your finger goes on and pulls to fire the gun. A “trigger bar” connects trigger shoe to the sear/sear system. (and that little gold “strap” thing in the photo is metal, btw)

I explained the question of different masses and travel directions in another comment above. Well, as best I can. Simply looking at a picture of the parts and 1) assuming the bar is heavier than the shoe 2) completely guessing in the dark as to how much heavier 3) assuming they both travel on the same plane 4) assuming they have equal leverage on each other…is taking giant leaps of guess work and presumption.

We KNOW the heavy trigger shoe results in rearward travel on impact and the light trigger shoe does not. Enough said. The inertia of the trigger shoe matters. Proven in high speed video and proven in the end result (no discharges). If trigger shoe and trigger bar ARE fighting each other for dominance in impact as you describe, SIG has proven that lightening the shoe takes it from winning the fight to losing it.

36. TommyJay says:

Thanks J-, Jeff, and Jeremy S. for the info and responses.

To Jeremy,
I have the Sig exploded diagram. The thing you call a trigger shoe is called a trigger.

https://www.pinterest.com/pin/323625923203174750/

“If trigger shoe and trigger bar ARE fighting each other for dominance…”
Either the trigger bar moves in the opposite direction to the trigger pull or it doesn’t. (In my XD they move in opposite directions, and in my CZ-75B they move together.) So the exploded P320 diagram tells me you should have responded YES to my question 2). Thanks.

This stuff is important because it suggests that the Sig engineers weren’t stupid, and maybe the CZ engineers in the 1970’s were a bit stupid. The Sig engineers just didn’t run enough FEA simulations and drop enough firearms onto concrete.

I’d really like to see side-by-side photos of the old and modified trigger group parts. I take it you don’t have any replacements yet.

I’m shocked that there is nothing on the Sig website about any of this.

PS: TTAG made it into Wikipedia on this topic.

37. Hannibal says:

A gun channel on Youtube (TFB TV) managed to get a discharge quite easily by striking the back of the gun- IE no drop, and no apparent trigger movement.

Makes you wonder.

• James Earl Hoffa says:

That’s simply because most people didn’t read the entire article above. There are two separate issues going on with this pistol. The frame is flexing enough to cause the Seer to release the striker which is at a 90% caulked rate to improve trigger fill. As soon as the Seer disconnects from the striker the firing pin flows full word and ignites the primer which ignites the powder which puts the bullet out the barrel. This gun is a turd.

i have had a sig p226 for years. great gun never had any failures. i wanted a smallish carry gun to carry with me in my work case. got a glock 42. it was the worst jamming POS gun i have every had…. i saw stuff all over the internet about it jamming and some people would get glock to send it in and replace parts. so, i called glock support and they told me to try different ammo instead of sending it in or break it in…. Well i bought it used and had already fired several hundred rounds thru it. Tried all kinds of ammo and anything but ball ammo would FTF on a regular basis. some low recoil rounds FTE. And no, i’m not “limp wristing” the gun. hang on bad guy, i need to swap ammo?. so i traded it on a p320 carry. love it. shoots great. best shooting handgun i have ever shot. never a malfunction. hope they get it resolved and they don’t charge for it. not that i plan on dropping a loaded weapon but it is a little scary that it would fire.

39. Galvinized says:

So I am assuming by some of the comments here that either some folks aren’t aware of the slam fire issues with early Glocks or there’s just a convenient memory loss. I am an admirer of both Glock, SIG and several other manufacturers. The issue with the P320 has just came to light although the gun has been out for a good while. Not saying it doesn’t need to be addressed but obviously the propensity for this malfunction is minimal and -outside of these tests- has not been reported to have happened to an operator.

• James Earl Hoffa says:

Ttag already covered an incident where a police officer had dropped his duty belt containing a P320 in his holster and the gun went off hitting him in the leg and lodging somewhere around his knee. So yes there has been an injury due to this problem.

• Galvinized says:

So, I guess I’ll just have to remember not to drop my P320. But, to my original post, the folks with the Glock vs. SIG comments might want to review Glock history. Glock was genius but still had to work out some early bugs. There are several safety recalls going on with many manufacturers but it would take more to turn me against a manufacturer altogether. Especially if they are quickly proactive about the solution.

40. Mark Horning says:

The M17 has a manual thumb safety.

Not familiar enough with how it is implemented. Does it block rearward travel of the trigger assembly or physically impede the striker?

Either way, has anyone tried this with a thumb safety equipped version?

• The M17’s other changes, outlined in the post here (what owners will receive if they do the voluntary upgrade), resolve the issue. I’m not sure if the thumb safety (not included as part of the voluntary upgrade) activates the trigger disconnect and therefore renders the trigger inert or if it physically blocks it or what, but I’ll find out tomorrow and let you know!

• Hey Mark, SIG told me that the thumb safety mechanically blocks the trigger bar, physically preventing it from moving.

41. drmorrish says:

I’m just gonna come out and say it. I’m a sig fanboy and a glock fanboy. I shoot both often and carry both on and off duty in a professional capacity. Now that I’ve made my full admission, I have to say the last two sig’s a 229 in 9mm and a p320 in 9mm have now both had to go back to sig because of of serious problems. My 229 had a factory bend in some part and wouldnt fire BRAND NEW OUT OF THE BOX. The 320 obviously for the drop issue. What is happening over at sig? I want my old W.German made P228 back.