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This is the trigger safety on a Glock pistol. It is the only external safety on the gun, and it is an automatic safety, meaning that if you operate the gun normally it will fire without manual deactivation of the safety.
Basically, if you pick up the gun and pull the trigger, it's going to shoot.
If this makes the safety sound decidedly unsafe, do not be alarmed. This is a feature, not a bug.
There is some argument about this, but the thought is that Glock needed another safety to meet the requirements of the most law enforcement organizations (their target market). So by adding this safety, they could say it had three, count 'em, three safeties, and is therefore sooper safe and totally fine for cops to use safely.
The problem isn't that they designed with their audience in mind, but that the idea somehow managed to catch on.
Now we've got guns of all kinds that have trigger safeties on them (with a wink and a nudge when I say the word "safeties"), and they are absolutely pointless.
Well, not absolutely pointless, the only lipstick on that pig is in situations where something brushes against the side of the trigger without actually pushing on the middle of the trigger, the trigger will be locked in place, and the negligent discharge will have been averted.
But on the Smith and Wesson M&P pistol series, we've got trigger safeties that are built into the entire body of the trigger!
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If you push on this trigger, anywhere but at the top, it will deactivate the safety. (Of course, if something is pushing on the top of the trigger, that nice little curve guarantees whatever is pushing will slide down to the trigger safety portion and deactivate the safety anyway!)
Next is the Bersa BP9CC (which is an EXCELLENT gun, by the way), which builds the entire safety into the rocking motion of the trigger!
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If you push on the trigger anywhere, it's going to shoot.
Can we please stop this?
Trigger safeties are NOT safeties, and that's OK!
We're big boys and girls, and we realize that our safety is between our ears, not attached to our triggers.
Can we just skip the formality, and make guns that don't have any external safeties?
"Oh, but the extra safety there just gives me piece of mind!" Does it really? Because if so, simply remove the trigger safety from the gun, and put it under your pillow, because it'll do about as much good there, as it would on your trigger.
I don't have a problem with safeties, some people really want a manual safety on their gun. What I DO have a problem with is a bang switch masquerading as a safety.
Lets skip the pretense and skip trigger safeties.