What exactly is a "no thumb safety?"

In reading a little about various handguns, I see some claim to have (a) no thumb safety. Just what does that mean? I get the sense that it doesn’t imply no safety at all, but rather that the safety mechanism(s) don’t include a thumb-operated lever. Is that correct? Would it be accurate/helpful (to me, anyway) to call it a “non-thumb” safety?

Here’s a handy list and explanation of various common types of gun safeties; most of them do not involve a thumb switch.

When people talk about a thumb safety they usually mean a little switch that can manipulated by the thumb without removing one’s hand from the grip. A good example of this is the AR-15/M-16 series, which has a thumb selector switch.

Many guns instead use cross-bolt safeties in which you must push a button on the side of the gun. This places a physical obstacle in the path of the trigger mechanism. To reverse the procedure, you push the protruding button (actually part of the safety bolt) on the other side of the gun.

The other one you will hear a lot about are the Glocks, which include a little toggle on the trigger itself. The advantage of this is that the weapon is always “safe” until you touch the trigger and it does not require any additional steps (and as a general rule you should not touch the trigger until you are ready to fire). The disadvantage is that some people might prefer to take an affirmative step (eg pushing an external switch) to avoid accidental or negligent discharges.

I still don’t understand the idea behind the Glock safeties. With a gun without a safety, it does nothing until you pull the trigger, and then it fires. With a Glock safety, it does nothing until you pull the trigger, and then it fires.

Without a safety, what is there to keep the gun from firing without you pulling the trigger, e.g., when you accidentally drop it?

In a perfect world, a gun should never go off when you drop it, period.

But is it the safety that stops it?

Many autoloading pistols have a piece that blocks the firing pin or striker from moving far enough to contact the primer. There’s a bump on the trigger bar that moves this pin out of the way as the trigger is pulled. If the pistol is dropped and the sear releases the firing pin or striker this pin prevents the primer from being struck.

As far as the Glock Safe Action System goes, Google Glock Leg.

The link posted by DCnDC really goes into detail about the variety of mechanical means that firearms designers have used over the years, and is a great way to answer your question.

Chronos, the thing about Glock’s various safeties they use is that they allow for a safe, reasonably light, consistent trigger pull, in weight and reset distance, without requiring the disengagement of a manually operated safety, or the increased trigger weight from a initial double-action trigger pull. Single action only pistols usually have much better triggers—the stereotypical “breaking glass rod” of a good 1911 comes to mind—but they in practice require a manually operated safety for safe operation. (The thumb safety in the OP’s headline)

Moreover, single action pistols can and have—thinking here of the Colt Series 70—accidentally discharged when dropped. (So can striker-fired pistols like the infamous problems with the SiG P320) Due to all of the added internal mechanical safeties that a Glock has, they really can’t. Though nothing will usually stop a Glock from firing when a hapless user negligently pulls the trigger when trying to catch or grab the falling thing. Ask Plaxico. Or that idiot back-flipping dancing FBI agent.

Firearm safety mechanisms can be divided into three general categories: manual (external) safeties, passive external (grip or magazine) safeties, and internal safety (anti-impact) mechanisms. On many older designs like the M1911 pistol (the .45 ACP pistol that was the standard sidearm in the US Army until the mid-‘Eighties) and the Browning Hi-Power, the external safety allowed the firearm to be stored with a round chambered, hammer back (Condition 1), allowing it to be drawn and fired by flicking the safety off and pulling the trigger. This is a manual safety, as are crossbar/crossbolt safeties found on many rifles and a few pistols. The 1911 and the Browning Hi-Power are also what are known as single-acton autopistols, meaning that they can be fired only when the hammer is already retracted. (The “single action” is pulling the trigger and releasing the hammer sear, allowing hte hammer to fall.)

Passive safeties include things like grip safeties (found on the M1911) and magazine release safeties (Browning Hi-Power), as well as trigger safeties found on the Glock line of pistols, Springfield XD, et ceteras. They are passive because they are engaged automatically in performing other actions (loading or gripping the pistol, pulling the trigger, et cetera.)

Most modern pistols are either what is known as double action/single action pistols (the first action being to retract the hammer by using the trigger with a heavier and longer pull if it is down, and then releasing it…the action of the slide retracts it for subsequent shots allowing for a lighter trigger pull) or double action only/striker-fired/auto-cocking, in which the pistol is carried either in the hammer down state, or with a striker that is partially cocked but requires deliberate trigger action to complete the cocking and release. These pistols don’t generally require a manual safety that allows the pistol to be stored with the hammer back (although there are exceptions like the CZ-75 or HK PXX pistols, which offer Condition 1 carry as an option), and instead have either a decocking mechanism (Sig Sauer P2XX), an integrated safety/decocker (Walther PP series, most Beretta service pistols, S&W 2nd and 3rd generation) or no kind of decocker at all (Glock, Springfield XD, et cetera).

All modern service pistols from the late ‘Seventies onward have some kind of integrated anti-impact safety which blocks the action of the firing pin, disengages the trigger bar, or restrrains the hammer (some have all three) to prevent the gun from firing if dropped, requiring full action of a finger on the trigger. (Older pistols like the original M1911 and Browning Hi-Power do not have these safety mechanisms, and carrying them hammer down on a loaded chamber is actually a dangerous practice because they can potentially go off if impacted in just the right way.) These safety mechanisms are internal and invisible to the casual user, and although there have been a few notable failures they generally perform flawlessly throughout the service life of the pistol with no maintenance or replacement required.

Some people believe (falsely) than an external safety makes a gun safer to handle in the case of someone violating Rule #2 (“Keep your finger off the trigger until the sights are on the target.”) Other people believe (falsely) that pistols with external safeties are less safe because if the shooter leaves it off they might accidentally pull the trigger. The reality is that as long as you don’t pull the trigger, a modern, well-designed and maintained pistol won’t go off. The reason to have an external safety and carry in Condition 1 with a single action pistol isn’t that it prevents the trigger from being pulled but to reinforce trigger discipline by having to handle the pistol in a particular flow. Conversely, carrying a DA/SA or DAO pistol without an external safety is not ‘safer’ because of that heavier, longer pull, which should not be relied upon to compensate for poor trigger discipline (see Rule #2 above).

The point of the Glock Safe Action is to make the pistol ready to be used without any external mechaisms that can be forgotten, broken, or snag on clothing. I am not personally a fan of the Glock ergonomics or what the trigger safety does to trigger feel, but it is a reasonable approach to ensuring the inherent safety of the pistol to impact while minimizing manipulation under stress, and some variation of that mechanism has been adopted by numerous manufacturers, sometimes to the point of violating the intellectual property of Glock (e.g. the S&W Sigma). I personally favor the Sig Sauer P2XX DA/SA pistols but that has more to do with ergonomics (they all feel very much like the single aciton Browning Hi-Power I originally learned to shoot on) and their high build quality and reliability than some inherent safety advantage.

Ultimately, what makes a firearm safe has less to do with any particular safety mechanism within it than the person wielding it. All firearms are definitionally hazardous tools, and no safety mechanism will make an irresponsible or poorly trained user ‘safe’.


All modern handguns should be drop safe. When they’re not (hi, unmodified SIG P320), it’s not intentional and a major fault.

Reading behind the lines for the OP, I imagine it is in the context of a selling point. Self defense guns have one of these: a) a manually-operated safety, b) a consistent trigger pull that is sufficiently heavy to not be hit by accident, or c) the same as b, except subsequent shots have an easy to pull trigger because the hammer is already back. In many cases, category © instead comes with a decocker to safely return the hammer down. There are many schools of thought, but while some people prefer (a), others think it is an excessive complexity, and manual safeties are unnecessary because you should be practicing trigger discipline anyway.

Many modern handguns have an internal device specifically called a “drop safety”.

I normally don’t want a manual safety on my handguns. But I sometimes carry my Glock 26 in my front pants pocket covered by a sweatshirt using Clip draw. But don’t like the idea of blowing one of my nuts off. So I installed a Siderlock safety.

Thanks for the, as usual from you, very detailed and informative answer. Which, IMHO, flowed better than the article at DC’s link.

I do question the statement though that the external safety is there merely to reinforce trigger discipline. It also prevents inadvertent manipulation of a trigger that, unlike one with a Glock or other typical striker-fired trigger safety, could be moved by a very slight amount of force (EDIT: On the side of the trigger, not otherwise touching the trigger safety bar. Like what might happen in brushing against the side of clothes, skin, or a holster) to discharge the pistol. I want to say that typical trigger weights for a cocked SAO or SA/DA pistol are on the order of 2 to 3 pounds, and require a rearward trigger movement that’s much smaller than that required to pull a Glock trigger at full extension or a typical DA trigger pull.

Otherwise, why not carry a 1911 cocked and unlocked (though there at least still has a grip safety), or a DA/SA like a Sig P220 with the hammer already cocked? I mean the holster should prevent any inadvertent trigger manipulation, and this would result in an easier first shot, right? I’d think the safety in those cases has more function than just reinforcing what we should already be doing. Though again you’re right in that most of the issues would be solved if people would just follow the damned four rules already.

Same here.

This is getting into IMHO territory, but I do not want an external safety on my self-defense handgun. I see absolutely no point in it; I only see disadvantages, not advantages.

OTOH, an external safety on a long gun (shotgun or rifle) is a must. This is because a long gun is carried in the hands, and a twig or something can get inside the trigger guard and touch the trigger.

Agreed. I’ve shot many handguns and at various times I’ve carried for professional reasons. A manual safety switch just adds an extra step to what will probably be a fast, stressful, and confusing situation. The appeal of the Glock is that the safety is automatically released when the trigger is touched, on the assumption that you won’t touch the trigger until you are ready to shoot.

But it does mean accepting more risk on the user’s part. People have shot themselves for astonishingly stupid reasons. Maybe their dog stepped on the gun, or they tried to catch a falling gun, or they got too enthusiastic during a demonstration (Google it). There are many people who would be better off if they had taken advantage of an affirmative “safety” step.

Edit: PS… Glocks have a reputation for being very safe and impact resistant, but there were documented cases of mechanically defective Glocks that misfired even with no negligence on the user’s part. There is no such thing as a truly “safe” firearm!

The pull force (‘weight’) of trigger pull on a single action duty pistol is typically somewhere between 4 and 7 lb[SUB]f[/SUB]. While light, it shouldn’t pose danger of inadvertent operation as long as good trigger discipine (including keeping the trigger guard clear or obstructions) is maintained, and the manual safety should not be relied upon as it is all too easy to sweep it off during handling. There are people who do or at least did carry in Condition 0 (“cocked & unlocked”).

I personally learned to shoot with single action pistols, primarily the Browning Hi-Power and never found the safety and trigger discipline difficult to master, but I’ve come to appreciate DA/SA and passively safe striker fired systems, although I am still not enamored with the Glock for reasons unassociated with the safety system.


With the rare exception of using the clip draw my weapons are always carried in a holster. Which means the trigger is covered and little chance of a negligent discharge. A self defense handgun should be draw and fire.

In fact, the written policies of the department I work for specify that officers carrying a weapon that has a manual safety that the weapon is to be carried with the safety turned off and the weapon ready to fire with just a pull of the trigger.

But those little .380 pistols and such that can be carried in a pocket, I would prefer the option of a safety.

Pocket holster, I’d hope. Not the pocket with nickels floating around in your trigger guard!

Desantis makes nice pocket holsters. Nemisus is what I use.