Striker guns, technical question

O

OhioGuy

New member
Let me preface this by saying I am not attempting to start any kind of flame war for the billionth time...I'm just trying to get a technical answer to help me understand things better.

This question is about whether there are any mechanical design differences among the usual striker-fired poly guns that cause them to substantially differ from each other in safety, especially for carry.

I often see and hear comments that leave me confused. Like someone who carries an M&P without a safety, but says the trigger on some other gun is "too light for safe carry."

I think this simply boils down to some intangible level of comfort that has to be determined by each individual. That's clear. But anyway...

1. Assuming that all mechanical components function correctly and according to design (this would include all internal passive safety mechanisms), and

2. Assuming all models being discussed are those without active (i.e. thumb-activated) safeties, and

3. Assuming the gun is always properly carried in a rigid holster that fully covers the trigger...

Then, is there anything mechanical that inherently makes any striker fired gun more, or less, "safe" to carry? Or do all concerns apply equally across the board?

And so far as I can tell, the only genuine concern to have here comes down to a finger, or some foreign object, pulling the trigger rearward when it shouldn't. Is this a correct statement?

Assuming the gun is holstered properly, then the only times when this would be a concern would be when removing from or inserting into the holster, or when doing some other operation such as loading/unloading or press-checking. Also a correct statement?

The trigger weights of pretty much any striker gun seem to fall somewhere in the 5.0-6.5 lb range. All are light enough that exerting any appreciable force on the trigger will result in a loud noise when it isn't wanted...

So I have to conclude that, among popular striker guns (take your pick, Glock, M&P, PPQ, VP9, XD, Ruger American, and Lord knows how many others), all could be considered equally "safe" to carry. Or "unsafe" depending upon your terms :)

Does anyone disagree with my conclusion based on mechanical or other design factors?

Please do not make any comments about DA/SA being better, or DA revolvers, or anything else. I just want some insight into a specific, focused aspect of one type of pistol.

Thanks in advance.
 
Striker IS double action. Your finger actuates the striker fully, so there is always going to be a minimum pressure required to move the striker All the way back. The only true, single-action striker (it has a safety) was a Walther (can’t remember the model), and it didn’t sell.

The short answer is they’re all about the same, and while you can do a little to the trigger there is a limit. It’s not a release like on a SA. This is very hard for people who like a glassy trigger to understand. The break can’t be made like a glass rod, but you can become used to it so it doesn’t matter. I think match scores bear that out.

I don’t think they’ll ever be the most popular in bullseye, but they certainly dominate lots of others.
 
I frequently carry a Keltec P-11 sans holster in my front pocket. With it's long 8.5-10lb trigger pull, I consider that "safety" enough. I also own a Glock 26 that is only carried in an IWB Kydex holster that shields the trigger completely. I treat the trigger of the Glock with much respect. Always extremely cautious and careful when unholstering or holstering the pistol. Touch the G26 trigger and the gun goes bang! I assume all striker fired pistols have the same light trigger action.
 
So I have to conclude that, among popular striker guns (take your pick, Glock, M&P, PPQ, VP9, XD, Ruger American, and Lord knows how many others), all could be considered equally "safe" to carry. Or "unsafe" depending upon your terms
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I would say that is substantially correct, after defining them as you did as without an external safety. The trigger weights may differ somewhat, but most are in the same general range. The degree to which they are pre-cocked can also vary, but if the trigger weight is similar and some sort of drop safety mechanism exists, that matters little to overall safety.
 
JMHO and that's worth exactly what you paid for it but. The Springfield's grip safety adds a measure of safety.
As for the rest I would think the blade trigger safety IE Glock would be a hair safer than the hinged style IE M&P since it would be conceivable to catch the corner of the Glock trigger without depressing the blade.
Maybe 1/2 a hair cause I think I'm really splitting hairs lol.
 
For the most part... All are safe... Especially given your listed conditions. It's outside those conditions that the question of inherent safety would be more appropriate.

From a purely mechanical viewpoint... The Glock action is likely the most inherently safe trigger mechanism, of all the striker pistols that I am mechanically familiar with.

The striker is only about 50-60% tensioned, and that means it doesn't have enough force to ignite a primer if it was to fall from that point.

The trigger bar also sits on a shelf that prevents the bar, and subsequently the sear surface that is part of the trigger bar, from moving downward. That prevents the whole thing from moving inadvertently and releasing the striker.

Then you have striker block, which is fairly redundant given the above...


All in all, minus the inadvertent wandering trigger finger... The mechanism is probably safer than many hammer fired designs, especially ones from before the common practice of firing pin blocks.


Other striker designs are potentially less safe, especially the ones with rotating and dropping Sears, like the M&P, VP9, PPQ, and others...

The recent debacle with the 320 has shown that the simple elimination of a trigger safety was enough to cause a potentially unsafe condition. Even without a trigger safety, i find it likely that a Glock mechanism would not have the same problem. Simply due to the geometries involved.

But it's more "hypothesis" than "practical" when it comes to most other striker designs, and any perceived lower safety... The 320 was an example of removing too much redundancy, to the point of failure. Due to the fully tensioned nature of the design, and the rotating sear... There is just less redundant safety function. Other designs are similar, but wisely included the trigger safety.

I would trust an M&P, VP9 or other quality pistols.
 
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Your conclusions are largely but not completely correct. The SIG P320, which I own two of and consider to be an excellent striker-fired pistol, has been shown to drop fire if dropped muzzle upwards angled 30 degrees off the vertical. When dropped at this angle, the back of the slide impacts the ground with maximal force, none of the impact force being buffered by the tang or "beavertail" of the plastic grip module. This can result in sufficient trigger travel due to inertia to disengage the striker safety block, in conjunction with enough "sear bounce" to release the striker.

There is one police officer suing SIG Sauer for injuries sustained when he says he dropped his holstered pistol and it discharged. More recently, another LEO claims that his P320 discharged when holstered when he fell. The P320 does not have a trigger tab safety like the Glock or the vast majority of other striker-fired pistols. The trigger tab safety is intended to prevent inertial trigger travel. SIG is addressing this issue through what they call a free "voluntary upgrade".

The original Ruger SR9 was another striker-fired pistol without a trigger tab safety that was found to have drop-fire issues and was recalled by Ruger. The recalls were retrofitted with a new trigger group which included a trigger tab safety.

Glocks and many other striker-fired pistols require dry firing the pistol to release the striker before removing the slide for cleaning. There have been a substantial number of negligent discharges with this type of pistol that occurred when the handler did not properly clear the chamber before pulling the trigger. Some have resulted in injuries and some have been fatal. It is easy (and correct) to say that this type of discharge should never, ever occur, but the fact is that it has quite a few times.

The great majority of NDs occurring with striker-fired pistols have occurred during the draw from holster, when the shooter "got on" the trigger too quickly, or when reholstering when a foreign object entered the trigger guard. Nearly all of the reholstering NDs have occurred at the time of holstering, but I read of one incident with a Glock owner who shot himself in the leg when he removed his sweatshirt. The sweatshirt drawstring entered the trigger guard during reholstering, but the pistol did not discharge until he removed his jacket, and the drawstring pulled the trigger. I read of one other incident in which a Glock owner shot himself in the butt when scooting across a car seat with his pistol holstered in a nylon holster. There was enough "play" in the soft nylon fabric to get into the trigger guard and pull the trigger.

As far as the relative "safety" of different striker-action triggers is concerned, it is not just the weight of the trigger pull, but also the length of take-up and total trigger travel required to release the striker that comes into play. Although many striker-fired pistols call themselves "DAO" even if the striker is nearly completely tensioned by slide reciprocation, I have yet to shoot any striker-fired pistol with a trigger that approximates the length of pull required to fire a hammer-fired DAO pistol, or a double action revolver. The Kahr probably comes the closest, but it still requires far less trigger excursion than a true DAO pistol or revolver, or the double action trigger pull of a hammer-fired DA/SA pistol.

In my opinion, the length of trigger pre-travel and total length of trigger pull probably do more to reduce the likelihood of an unintentional or premature discharge than a somewhat heavier trigger pull does. As for Glocks, I have heard it said by gunsmiths that the striker is tensioned well over 50% by slide reciprocation and has sufficient force to result in primer ignition at least in some cases, if the striker is released by sear bounce and the internal safeties are somehow defeated. As striker-fired pistols go, I would tend to agree that the Glock has one of the "safer" trigger actions. Although the trigger action itself is pretty mediocre, there is a good bit of pre-travel. What's more, the trigger weight of the Glock can easily be increased, if desired, through a relatively inexpensive change of connectors and/or trigger springs.
 
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I believe the Sig 320 example shows that not all striker fired pistols are equally “safe”, or at least not as vulnerable to unintended discharge to the same degree or the same manner. As has been more or less pointed out, the manufacturers have built in safety features to prevent unintended discharges.

Of the striker fired pistols I'm familiar with (unfortunately, that is not very many), all have striker blocks. I would consider them to be at the top of my list of importance. When working properly, they prevent the striker from hitting the primer of a chambered round unless the trigger has been pulled (or at least traveled reward).

Trigger safeties, like the Glock and others offer an additional degree of safety. They are designed to allow trigger travel only if something (preferably a finger) is pressing on the trigger. Grip safeties are somewhat related, requiring pressure on the backstrap (preferably from a hand) to all the weapon to be discharged.

Another potential level of safety stems from the degree of striker preload; that is how much the striker is pulled (held) back against the striker spring pressure even with no trigger pressure applied. Since I'm not that familiar with that level of detail on the many striker fired pistols available, I'm not sure how many preload the striker in that manner. I know at least some do. The use of striker preload means some level of stored energy is present in the striker at all times (unless the trigger has been pulled and the action has not cycled; like the trigger being pulled on an empty chamber), and therefore has some potential for striking a primer should certain mechanical failures occur.

It would seem that a striker fired pistol with no preload would have the potential of a higher resistance to unintended discharges since no energy would be stored in the striker spring. The tradeoffs of such a design would probably add to the trigger pull weight, trigger travel and/or trigger reset. There may be some striker fired pistols with no striker preload (I simply don't know).
 
This question is about whether there are any mechanical design differences among the usual striker-fired poly guns that cause them to substantially differ from each other in safety, especially for carry.

I often see and hear comments that leave me confused. Like someone who carries an M&P without a safety, but says the trigger on some other gun is "too light for safe carry."

I think this simply boils down to some intangible level of comfort that has to be determined by each individual. That's clear. But anyway...
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Short answer, yes and yes.

It is a level of comfort. I find (for example) the Bersa BP trigger to be scary light, in the example that I handled. I don't know what's going on internally, but it's too light for my comfort.

The XD has a single action trigger (in the sense that the striker is fully tensioned, and pulling the trigger drops the sear only). I'm quite happy with having a grip safety that physically blocks that sear from moving.

Other guns have more margin.
 
These replies are awesome! I feel like someone needs to start a flame war so we can fit in with the rest of the Internet :)

Specific question: the M&P hinged trigger safety is supposed to serve the same basic purpose as the blade in Glock and similar designs, right? Which I understood to be concerned with adding a level of drop safety. Are hinged vs blade trigger safety designs just to versions of the same function? Has anything shown one design to be better than the other?

I never was keen on M&P until the 2.0 came out. And lately the Compact has really impressed me. I'm considering getting either that or a G19 (I prefer the Gen4 ergonomics personally).
 
To the point above about removing levels of redundancy:

The Glock has a partially tensioned striker, so some marginal degree of "safety" is inherent in the design. The XD removes that margin by fully cocking the striker, but adds another level of redundancy via the grip safety.

Is it correct to say that designs like m&p, PPQ, VP9 etc have simply gone one level of redundancy below Glock and XD? And the P320 went yet another level by omitting the trigger safety?

Or am I over generalizing?
 
OhioGuy wrote:
...is there anything mechanical that inherently makes any striker fired gun more, or less, "safe" to carry?
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In short, No.

A striker-fired pistol has a firing pin propelled by a compressed spring that is retained in the cocked position by some sort of mechanical stop.

A hammer-fired pistol has a firing pin that is free to move when struck by a hammer propelled by a compressed spring that is retained in the cocked position by some sort of mechanical stop.

If that mechanical stop is designed in such a way that the gun can be dropped, jostled, struck, beaten, etc. and it will release, there will be an unintentional discharge. The danger is not inherent to the striker versus the hammer, but how well the engineer designed the mechanical stop and how well it was fabricated.

Because a hammer-fired pistol has the additional step of the hammer falling on the firing pin to drive it forward, a hammer-fired pistol has an additional place for the engineer to intervene; placing a block between the face of the hammer and the back of the firing pin. But such a safety system only contributes additional safety if it is actually implemented and since your OP specified no active safeties, such a block would have to be designed so it that was automatically disengaged by picking up the gun or by pulling the trigger - and that would probably both lengthen trigger pull and make it heavier.
 
The hinged trigger, or blade inside the trigger like a Glock must be depressed to pull the trigger. Neither of those are a "safety" in the traditional sense. Without them it would be possible for the trigger to pull from inertia if the gun were dropped and it landed in just the right manner. That is the only function, to prevent the trigger from being pulled if dropped. The blade triggers on rifles such as Savage Accutrigger and the Ruger American serve the same function.

I don't know enough about the Sig 320 to understand how mechanically it is failing when dropped. I don't see how any of the other designs such as Glock, XD, Smith M&P or similar could do the same. I've dry fired one Sig. I liked it, but in my opinion that trigger is too light not to have a safety. It had a lighter trigger than most out of the box 1911's and I'd not want a 1911 with no safety. I'll probably buy one, when I see a version with the safety.

In a holster with the trigger covered I don't think it matters.

It may be based on familiarity, but the Glock seems pretty safe to me. You have a significant amount of take up, then a pretty crisp, consistent 5.5 lb trigger pull to fire the gun. It is true DAO and I KNOW exactly how much pressure to apply to get the gun to fire. Others I've tried have lighter pulls, or heavier, and were inconsistent. I'm often surprised when the gun discharges when shooting them.

I like the XD the least. The grip safety is the deal killer. It is far, far more likely to prevent the gun from firing when you really need it to fire than to prevent it from firing when you don't want it to fire. It used to be pretty common practice back in the day among those who carried 1911's to disable the grip safety to prevent this. And the 1911 grip safety is a far better design than the XD.

Then we have the striker fired guns with a safety. I'm used to 1911's so I don't have a problem with one if properly designed. I bought one of the M&P's a few years ago with the safety. I liked the idea, but felt that safety was poorly designed. The one available on the Ruger SR series or American pistols seem to work well.

I'd buy a Glock with a safety if it were well designed. In a holster it isn't needed. But it would be nice to keep a round chambered with safety on and use it as a night stand or glovebox gun. It is faster to keep the chamber empty in such cases than to try to remove the gun from a holster that is not attached to your body.
 
Sear bounce is the enemy of rotating sears.

The lack of a trigger safety allowed a combination of sear bounce and trigger travel, to effectively disengage all safety mechanisms and allow the gun to fire. Or it could be the way the striker block works, as it isn't a plunger on a spring, but a small lever.


With a trigger safety on other designs, you would just get a dead trigger as the striker fell against the striker block.


When you get into scenarios of NDs due to user error... That is a bit different than mechanical failure or weak points in design.


I don't know why people freak out over the XD grip safety, it only needs to be actuated about half way to disengage... If you have any grip on the pistol that allows you to pull the trigger, you are likely going to get the bang you expect.

The XD has the most SA like internals of the strikers I know. I don't find it an issue... I carried one years back.
 
There are varying degrees of "cocked". A Glock is partially cocked. The trigger draws the firing pin back further and then releases it.

The M&P along with the Ruger I played with are almost fully cocked and, the trigger moves the sear out from under it in almost a trap door fashion.

The Kahr is also partially tensioned. The Kahr is a very cool design as the trigger moves a two legged cam. One presses up on the firing pin block as the other draws the striker back.

But, every striker fired gun I have spent any time with is, for all practical purposes a cocked pistol. There is enough stored energy to fire if everything went wrong without the trigger being pulled.

With all of the great engineering going on, the modern, quality striker fired gun is quite safe and, I will carry one on my hip all day long. Much like a 1911.

However, I personally can't carry a striker fired gun (or a 1911) appendix. There is something about a cocked pistol pointed at my femoral artery that just makes me squeamish.
 
To the point above about removing levels of redundancy:

The Glock has a partially tensioned striker, so some marginal degree of "safety" is inherent in the design. The XD removes that margin by fully cocking the striker, but adds another level of redundancy via the grip safety.

Is it correct to say that designs like m&p, PPQ, VP9 etc have simply gone one level of redundancy below Glock and XD? And the P320 went yet another level by omitting the trigger safety?

Or am I over generalizing?
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Not at all. And you succinctly described what many fail to understand...there are significant differences.
 
Why then did the US Army stipulate a manual thumb safety on their selected contract pistol? (Sig P320)

I have striker pistols w/o a thumb safety (XDs) and have put quite a few rounds through them, but I still favor a thumb safety.

The grip safety on the XD will prevent things like the above sweatshirt drawstring accident. I shoot 1911s a lot too, and I don't think the 1911 grip safety is a "far better" design than the XD gs. I have never had a failure to engage the gs on XDs but have had it happen with 1911s with a full grip on pistols with no beavertail hump. And I'm not the only one that this has happened to.

Also, I don't see how the gs on the XD can prevent the gun from firing when you want it to fire. This simply has never happened to me with an XD but it has with some 1911s.
 
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