Why trigger safety on Glock?

[Skribs]

Not the issue, John. What are the odds that a Glock, when randomly dropped out of a plane and if it should discharge, will hit someone nearby on the ground? THAT is the issue.

 

[FIVETWOSEVEN]

I don't know how fast it would have to go, but I've seen tests done where they dropped a glock out of an airplane and the gun wasn't destroyed. I don't much care for glocks, but they sure can take a beating.

The speed I can think of that would cause that poly trigger to travel all the way and over come the 5.5 lb trigger pull would require a speed that I don't think could be achieved from falling out of an Airplane. The speed I'm thinking of would destroy any gun too.

 

[GLOOB]

I really don't see how the trigger could gain enough momentum to overcome the 5.5 lb trigger pull. I would imagine that the gun itself would be destroyed from such an impact considering the speed it would have to gain for that small polymer trigger to gain 5.5 lbs of force for the full length of travel on impact.

It's not a 5.5 lb trigger pull anymore when the STRIKER is also moving to the rear by inertia.
And it's also not just the small polymer trigger mass to consider. Unlike most DA/SA handguns, the trigger doesn't pivot around a pin, pulling the trigger bar forward. The trigger and trigger bar both move backwards, together. So you have to add the mass of the trigger bar, too.

The 1911 is also in the same boat as the Glock, in this one aspect. The trigger and trigger bar both move backwards. The grip safety on the 1911 does the same thing as the dongle doohickey on the Glock trigger. It prevents the trigger from going back unless it's properly pulled. This is the reason I wouldn't disable the grip safety on a 1911. I think the value of a grip safety in terms of preventing an ND when a twig or shirt tail negligently gets into the trigger guard is next to nil. But in terms of preventing an inertial discharge by way of the trigger of a dropped gun, quite important.

Also remember that it's not only the speed of the gun that's important. It's how it lands. If that gun fell from 10 feet onto concrete, that could be worse than dropping a gun from a plane into a wooded area where foliage and dirt disperse the impact. And even if the gun is destroyed in the act, that won't make you feel any better if you get shot.

This is one quirk of the M&P that bugs me. The hinged trigger safety surely works just fine. But from an engineering standpoint, the trigger-in-trigger design on the Glock and ( I hope, but can't verify since I don't own one) XD is obviously superior. When given an acceleration to the rear, they are balanced to lock tighter. The hinged trigger on an M&P would tend towards unlocking. Also, the grip safety on a 1911 isn't ideal for this duty, either, since the gun could land on the safety.

"It's there because the Army requires a manual safety" theory:
There's no way Gaston Glock would have added a redundant doohickey onto "perfection" just to satisfy an Army requirement. I mean, he would. But then when the trial was over, he'd a removed it. As he did with the picatinny rail on the first G21SF.

 

[sturmgewehr]

I really don't see how the trigger could gain enough momentum to overcome the 5.5 lb trigger pull. I would imagine that the gun itself would be destroyed from such an impact considering the speed it would have to gain for that small polymer trigger to gain 5.5 lbs of force for the full length of travel on impact.

I haven't tested this, but I agree. The mass of the trigger isn't sufficient to overcome the mechanical disadvantage it's at and fire the weapon if dropped from a reasonable height. I don't think it would fire if the "dingus" (my pet term for the lever) were absent and the weapon were dropped from an unreasonable distance, say 30 feet.

But as I said, I haven't tested this.

I believe the Glock would be just as safe without the dingus. Most AD/NDs happen when the trigger is actuated unintentionally. Someone either pulls it with their finger or something gets into the trigger guard like a jacket zipper upon reholstering.

 

[sturmgewehr]

It's not a 5.5 lb trigger pull anymore when the STRIKER is also moving to the rear by inertia.
And it's also not just the small polymer trigger mass to consider. Unlike most DA/SA handguns, the trigger doesn't pivot around a pin, pulling the trigger bar forward. The trigger and trigger bar both move backwards, together. So you have to add the mass of the trigger bar, too.

Very good point.

I would like to remove the dingus from a Glock, load a case with nothing more than a primer in the chamber then drop it a bunch of time from no ore than 10 ft to see if it goes off. My gut still says it won't. Perhaps if you dropped it from 30+ feet it would.

 

[TCBPATRIOT]

Ok here is just my 2 cents.

1. Your finger is a safety
2. A negligent discharge is 98% due to user error whether that be improper handling or unfamiliarity of the weapon.
3. Why would you ever drop a gun. At least what I was taught is that a gun doesn't touch the ground. The Marine Corps taught me that if your weapon is on the ground then you are too.

 

[GLOOB]

I would like to remove the dingus from a Glock, load a case with nothing more than a primer in the chamber then drop it a bunch of time from no ore than 10 ft to see if it goes off. My gut still says it won't. Perhaps if you dropped it from 30+ feet it would.

I saw a youtube vid of a guy doing this to "prove" his dingus-free Glock was safe. He dropped his gun onto concrete from waist high a few times. He managed to ding up his aftermarket rear sight and push it all the way to the right. After this one test, he declared victory.

If I were willing to do this, I'd affix the gun to a rail, so that it always drops exactly muzzle up and lands on the back of the slide (not handle), simulating what happens if it were to land on a rock, or something. I'd probably use a heavy hardwood block for a landing pad.

Here's what one poster on that vid says:

Take a rubber hammer and strike it on the back of the slide, The gun will fire. If you don't think it will tell that to a friend of mine when his Glock fell out of his holster hit on the rear of the slide and wet off. Just mised his private parts and went out his back.

I suggest getting the book The Glock in Competition and read page 15. The gun well fire when hit from the rear when the trigger safety is removed. You never hit the gun from the rear all of your drops were on the side.

Oh, yeah. That guy on youtube had a live round in the chamber! Yikes!

The other thing is why only waist high. Or even 10 feet? When you are handling or carrying a loaded gun, you might be at an elevated height, running or on a moving vehicle, or swinging your arm when a mishap occurs. Or the gun could be hit by a fast moving object/vehicle, which amounts to the same thing as dropping it. So holster height or even 10 ft high static drop testing doesn't cut it for me.

I do not believe it to be the SAFEST design. Consider this-A double action/double action only hammer fired pistol. While reholstering or handling, if you want to be sure it isn't going to go off, put your thumb on the back of the hammer and hold it forward. It isn't going to fire unless that hammer comes back first. These guns also typically have a drop-safety on the inside as well, so any pressure on the hammer isn't being applied to the primer unless the trigger is pressed. A glock could be inadvertently fired upon reholstering if clothing gets pinched in the trigger guard and edge of the holster, and you would not have an absolutely sure way of feeling that about to occur.

The ND poll on this forum strongly suggests that this type of ND is extremely rare. In fact, the presence of an external hammer is way more dangerous, due to the sheer number of decocking ND's that are reported. Sure, you could say all those decocking ND's are avoidable. All you have to do is leave a SA gun cocked and locked. Or use the decocker on a DA/SA (when it has one). But you could turn around and say all those shirttail ND's are equally avoidable using your God given ability to see and to feel foreign objects in a holster. And in the end, the statistics show what they show.

 

[Loosedhorse]

Getting back to the original question...

What kind of accidental discharge is the trigger safety on a Glock supposed to prevent?

None, IMHO. I guess we can all imagine a scenario where a piece of shirt grabs the trigger somehow and "pulls" it when the gun is pressed down into a holster; but such rearward movement of the trigger is prevented by the trigger-face lever. Seems like a vanishingly rare problem.

I think 9mmepiphany has it:

It was part of the original design as it address the military specification of inclusion of a safety which is manually disengaged before the pistol will fire.

That must be it; the silly trigger "safety" didn't even earn Glock a single extra "import point" from BATFE.

 

[GLOOB]

?!?!?!
Sorry if my last paragraph threatens to turn this topic off course. But most of my post, and the last dozen, are all directly on point regarding the original question. Did you even read them? They're discussing the predominating opinion of the forum regarding the trigger safety, (and the only one that makes sense, and perfect sense, at that), which is that it's a drop safety.

If you want to deride its usefulness as a shirttail safety, that's fine. I completely agree. But that's not what it's for.

Before you disable your Glock's "shirt tail safety," you might want to actually read those posts.

 

[sawdeanz]

I too had been wondering this for a long long time. I think gloob finally satisfied my logical approach to the question, and if smacking the on the back with a hammer indeed sets off a safetyless glock than that answers the question good enough for me. Also the glock website says it prevents discharge from lateral mvmt, so I guess that would be like if your holstered glock gets rubbed the wrong way on the side. This is why I am a little concerned about the M&P safety, a gun I'm considering, as it doesn't seem like it would prevent lateral mvmt (if such a thing has ever happened). Does the m&p also have a trigger like the glock or does it pivot?
I'm intrigued by the Beretta PX4 constant action, a DAO version that remains at half cocked, supposedly giving it a lighter pull than its traditional DAO version. It doesn't have any trigger safety that I know of, however it is also a hammer fired gun so maybe it doesn't matter

 

[Zerodefect]

Glocks don't have a safety.

That trigger thingy just prevents the trigger from go off if the Glock gets dropped........er, I mean thrown into the ground really hard.

 

[Jim K]

The "gizmo" on the trigger of a Glock keeps the trigger from moving back unless it (the gizmo) is depressed. Period. It doesn't stop the Glock from firing if dropped (another safety does that) or prevent firing if the trigger is accidentally pulled (how would it know what the shooter's intent is?). It COULD keep the trigger from moving if something pressed on the side of the trigger without pressing on the middle, something so unlikely as to be silly. It seems to me about as effective in the real world as a safe with the combination painted on the door.

I agree with those posters who have said it serves only so the maker can tell customs and BATFE that the gun really, honestly, so help us, truly does have a safety.

Jim

 

[Zerodefect]

If you remove the trigger thing, you can get the trigger bar to swing back if you pound the gun on a block of concrete hard enough.

It's an inertia thing. Where in the world that would ever happen, I don't know.

It really deosn't work too well if you play with dragging on the side of the trigger, it helps a little a guess, but if your dragging enough to apply force to the trigger, chances are you're going to bump the safety thing.

I've made some real aggressive test holsters. During foreighn object in the holster testing, whether or not the trigger safety was installed, was of little difference.

 

[GLOOB]

Wow, I just examined my Glock closer. I'm even more assured this thing is a drop safety.

Take the slide off your Glock. Push the trigger bar forward until the trigger resets. Now depress the trigger safety. What happens? The trigger shoots back. All the way.

When the Glock falls on the back of the slide, the "lightweight polymer trigger" doesn't need ANY momentum for the gun to fire. The trigger spring takes care of that. The momentum of the trigger and trigger bar just help.

Once the striker moves backwards due to the inertia of a muzzle up drop, the trigger spring on a (dingus-free) Glock actually pulls the trigger. This assures it follows the striker back. If the striker makes it back far enough for the sear to release, the trigger will break. On top of that, it'll stay there. The trigger won't go back forward until the slide cycles, again. The firing pin safety will be off and the sear will be unlocked for sure, at this point. The gun would most assuredly fire.

Without the dingus, the only thing holding a Glock trigger forward is the striker. Without that, the trigger actually pulls itself. This is why the trigger goes back by itself when you cycle a dingus-free Glock. But in this case, the disconnector is being tripped. When the gun falls on the back of the slide, the same thing will happen, but the disconnector will not trip!

 

[Zerodefect]

Exactly.

 

[Ferstlerslim]

I heard Chuck Norris could discharge a glock by dropping it.

Sorry, i'm of no help to the thread

Dave

 

[MythBuster]

"I believe it also blocks the firing pin. So if for some reason the pin strikes forward (from a drop?), it will hit metal and not the primer since the trigger safety is supposed to push that piece of metal out of the way for the firing pin to hit the primer."

Why do people post a response to a technical question when they do have even the slightest clue about the subject?