Why is it, that when people describe DA/SA...

[Thomas_81]

they always say that the first shot is double action?

As stated in my other thread, I am a newb when it comes to semi autos, but how is that true?

When you load a magazine, you have to rack the slide and chamber the round for anything to happen when you pull the trigger. When you do that, is the trigger not in single action for the subsequent shot, everytime?

Isnt a DA/SA pistol only in DA if a round is chambered, and then the gun is decocked? Since at least half of the modern semi autos dont have a decocker, or even an external hammer, why is DA/SA universally explained this way? Is it not reasonable to assume that since most people dont carry, and fewer still carry with a round chambered, gun deocked, that most users will almost never pull the trigger in DA?

What am I not getting here?

 

[wild cat mccane]

you will do well here you nailed something most people repeat incorrectly over and over.

Few have decockers. That is why the the few that do are so awesome.

 

[REAPER4206969]

This thread is blowing my mind, man.

 

[LiveLife]

My Sig226 with external hammer had a decocker and with the hammer dropped (decocked) with a round in the chamber, first shot was DA followed by SA for subsequent shots. I describe such pistol as having a DA/SA trigger.

My striker fired PT145 did not have an external hammer and came with a safety. Since there is no way to release the striker with a round in the chamber (cycling the slide to chamber the round "cocks" the striker), first shot was SA followed by DA in case the first strike did not fired the round. I describe such pistol as having a SA/DA trigger. Taurus calls them "multi-strike" trigger.

I hope I did not confuse you further.

 

[KodiakBeer]

The normal (and recommended) carry mode for a DA/SA is hammer down, whether it has a decocker or is let down with the thumb.

The issue is not just the long and heavy DA shot, but that the trigger type also makes the SA shot sloppy and stagey. It's the worst of both worlds. At least with a Glock or DAO pistol, you get the same bad trigger pull with each shot. It's consistent if nothing else.

With a 1911 or Hi Power you also get consistency, but each shot is a crisp single action pull similar to a rifle.

The best argument is to simply dry fire each type of trigger one after another. The advantages and disadvantages become quickly apparent.

 

[Viper]

The normal (and recommended) carry mode for a DA/SA is hammer down, whether it has a decocker or is let down with the thumb.

The issue is not just the long and heavy DA shot, but that the trigger type also makes the SA shot sloppy and stagey. It's the worst of both worlds. At least with a Glock or DAO pistol, you get the same bad trigger pull with each shot. It's consistent if nothing else.

With a 1911 or Hi Power you also get consistency, but each shot is a crisp single action pull similar to a rifle.

The best argument is to simply dry fire each type of trigger one after another. The advantages and disadvantages become quickly apparent.

My assessment is different from yours. I have been shooting DA/SA SIG's for over 30 years, and I really like the system. In fact, I bought a DAK P220 a couple of months ago, and returned it because I didn't like the trigger. Several of my pistols including one striker fired gun are DA/SA, and that's the trigger system I prefer to carry. I do like the 1911 and HP SAO triggers for target shooting, but would much rather carry a DA/SA.

 

[COLOSHOOTR]

I think you are getting too hung up on one type of operating mechanism. There are several different types of operating mechanisms used on modern firearms. The most common are SA (Single Action: meaning the trigger only does one function and that is releasing a pre-cocked hammer) and DA/SA (Double Action: pull off the trigger completes two things cocking the weapon and releasing the cocked hammer and the SA once cocked releasing the cocked hammer as stated above). Another type is DAO (Double Action Only) where you pull the trigger and the weapon cocks itself and fires. Then there are the striker fired systems that are kind of a hybrid in my opinion.


A SA type system would be your 1911 style weapon or a old Colt Peacemaker that requires you to cock the weapon before it will fire. In the old revovers you have to keep manually cocking the weapon. In the autos like the 1911 the slide will cock the weapon for you after each shot. SA autos like the 1911 are generally carried cocked and locked meaning hammer cocked safety on.

Your traditional DA/SA system is something like the Beretta 92FS or a Sig 226. When you chamber a round you then decock the weapon prior to carry by using the safety on the 92 and the decocking lever on the Sig. Each shot you then fire after that cocks the weapon resulting in a SA pull There are many makes/models with a similar type system. Most DA/SA systems have some sort of decoking system with a few exeptions like the above posted PT145 that does not have a decocker.

The next type of system is a DA only system. A Kahr P9 is a good example of this as well as many different revolvers. Each time you pull the trigger there is the same long trigger pull. As a safety system the pull is usually quite long and heavy in comparison to SA systems. Most of these models do not have a manual safety with a few exepions. Some have hammers some do not.

The last type I'll go over is the PRE SET (<--key word) striker system. There is a lot of debate over this type of system with some claiming they are DAO because of the consistant trigger others that they are SA because they generally have lighter trigger pull weights then the DAO systems. I personally think they are kind of a hybrid but closer to a DAO system. When you cycle the slide the firing pin (stiker) is under partial tension (not enough to set off primer if released) and when you pull the trigger it cocks the stiker the rest of the way and goes bang. The most common example of this is the Glock. These do not have a decocker because they are not fully cocked so there really is no point of having one.

Some stiker fired systems like the PT145 and the Walther P99 are a DA/SA type allowing for a second stike if your first trigger pull fails to set off the primer due to a light strike or hard primer. The P99 does have a decocker button on the rear of the slide.

There are many variations of these different systems and some weapons may be different so this is not the end all be all list of systems. It's just a basic overview of the popular systems.

BTW there is a good sticky in this section describing the different systems!

 

[The Lone Haranguer]

When you chamber the first round on a DA/SA pistol, the hammer (or striker, on some) is cocked. Then it has to be decocked. Almost all such pistols have a decocking mechanism of some sort so neither the trigger nor hammer has to be touched when doing so. The gun is then ready to be fired with a DA first shot, all subsequent shots SA.

 

[SleazyRider]

Well said, Coloshootr, well said.

 

[bigfatdave]

http://www.genitron.com/Basics/Beretta92/New-Beretta-92.html

There's a detailed interactive animation of one of the most common DA/SA pistols in the world. It demonstrates the internal workings of the decocker (one version) and the trigger's linkages to the hammer for cocking it and releasing it.

 

[Thomas_81]

So, due to the fact that the trigger can perform the action of cocking the hammer/striker under a specific circumstance, the pistol is considered DA/SA for that reason alone, and not necessarily because this is a primary function of the trigger under "normal" operation?

Makes sense, but I still don't understand why so many people fail to point that out in gun reviews. The "cons" of a DA trigger on a DA/SA pistol, seem to be almost completely irrrelevant, given how most people intend to use their pistol.

 

[Onmilo]

The term Double action really only applies to revolvers that allow the option of firing all shots by trigger cocking the action or firing all shots by manually cocking the hammer for each successive shot.
Some semi auto handguns will allow you to do this but you must first decock the weapon after each round is fired adding another manual operation to the sequence.

I like the term "trigger cocking semiautomatic" or "trigger cocking first shot semiautomatic".

Old timers called pistols that could fire off rounds simply by pulling the trigger "trigger cockers".

 

[JohnBT]

"The normal (and recommended) carry mode for a DA/SA is hammer down"

But, but, but...

My FNP-45 USG is DA/SA with a decocker. But, there's that word again, it also has a safety (push the decocker lever up) that allows it to be carried locked with the hammer back for a SA first shot.

John

 

[mgmorden]

3 of my 10 handguns are DA/SA, and all three have a decocker. Yes, the hammer is left cocked if you rack the slide to load it, and so at the range all my shots are SA, but when CARRYING them I decock the gun - so the first shot will always be DA.

Even without a decocker, virtually all guns that aren't DAO (which often have ground-down hammers) can be decocked just by thumbing down the hammer. Do it carefully and slowly with the gun pointed in a safe direction in case it does go off, but it's something that you can easily do. Most guns that don't have a decocker tend to have a rather extended hammer anyways to help with this.

 

[2WheelsGood]

There's a lot of confusion these days about what DA and SA even mean. Leave it to Mas to clear that up. GREAT READ

 

[rellascout]

So, due to the fact that the trigger can perform the action of cocking the hammer/striker under a specific circumstance, the pistol is considered DA/SA for that reason alone, and not necessarily because this is a primary function of the trigger under "normal" operation?

Makes sense, but I still don't understand why so many people fail to point that out in gun reviews. The "cons" of a DA trigger on a DA/SA pistol, seem to be almost completely irrrelevant, given how most people intend to use their pistol.

You are making gross assumptions which IMHO are not accurate. As COLOSHOOTR pointed out there are 3 basic types of semi-auto actions. You seem hung up on the DA/SA type.

The manual of arms for a carrying a DA/SA pistol is decocked/hammer down on a chamber round or hammer down on an empty chamber. No one who knows anything about guns carries a DA/SA pistol cocked unless it has a mannual safety like the CZ 75B or FNP45 USG which are hybrids IMHO.

Your assumption which I think is stearing you the wrong direction is that you are taking your subjective use of a DA/SA pistol, range shooting, and applying it to everyone. I always carry a DA/SA pistol decocked/or hammer lowered on a chamber round. As a result when I shoot at the range I decock the weapon a lot. I shoot a lot of 3 shot strings DA/SA/SA decock. My range time practice mimicks the anticipate real world use.

So for me and my "intended" purpose the DA trigger of a gun is very important. It is a matter of perspective.

 

[JohnBT]

"unless it has a mannual safety like the CZ 75B or FNP45 "

HA!!!!

The "FNP-45" is DA/SA

The "FNP-45 USG" is DA/SA with the decocker lever also working as a safety if pushed up.

Don't you love guns?

 

[Sam1911]

The "cons" of a DA trigger on a DA/SA pistol, seem to be almost completely irrrelevant, given how most people intend to use their pistol.

That's kind of like saying, "this car can't turn left, but that's completely irrelevant, given how most people drive straight."

The raison d'etre for a service-style sidearm is to be carried, ready in an instant to be fired in an emergency. Target range plinking and even high-precision target competition (bullseye) are secondary purposes which give folks a way to practice with and compete with a style of guns designed for emergency defensive use.

If all you ever intended to do with a firearm was unbox it at the range bench, load it, fire it, and box it back up, there wouldn't be any need at all for a safety of any kind. The gun is either being fired or it is unloaded and safed.

ALL service style handguns sold today are designed with the intent that they will be or could be carried by law-enforcement officers, military personnel, and/or armed citizens. The fact that only half of those guns (or whatever) ARE routinely carried defensively doesn't change their purpose, or the nature of their firing system.

So, the ability to decock (either manually or with a decocking lever) a sidearm gives the carrier a perceived safety bonus, as the long, heavier first trigger pull is (in theory) harder to accidentally discharge than the traditional light, short single-action pull, and/or does not involve the (debatable) "complexity" of having to remember to disengage a safety lever.

As pistol designs have evolved, many users have come to view the difference between the long, heavy first pull and the shorter, lighter subsequent pulls as a negative aspect.

So, try not to view handguns as though they were top-fuel drag cars -- assuming that "most owners" want to go 300 mph, 1/4 mile at a time.

 

[Thomas_81]

You are making gross assumptions which IMHO are not accurate....

Your assumption which I think is stearing you the wrong direction is that you are taking your subjective use of a DA/SA pistol, range shooting, and applying it to everyone. I always carry a DA/SA pistol decocked/or hammer lowered on a chamber round.....

For an experienced owner who does carry, none of this applies, because you already know the various basic functions of the weapons you may be researching. I am simply talking about how this is typically explained to a novice...even on this board, stickied at the top of the page...

"DA/SA...These pistols fire the first round Double Action, and all following shots are fired single action."

If I am a novice, I read this, then go out and buy a Beretta 92FS... load the magazine, rack the slide, take the safety off, and fire...Im going to be pretty confused when the first shot is not fired in Double Action. I wasn't told that the first shot will be fired in Double Action if I decock the hammer after a round has been chambered, then pull the trigger, only that the first round is fired in Double Action... which wasn't true, in this example.

That's my only point. Until you read/watch enough, and can get a mental picture of what is going on mechanically inside of the firearm, this is a pretty terrible way of explaining it, imo.

 

[bigfatdave]

Until you read/watch enough, and can get a mental picture of what is going on mechancially inside of the firearm

Did you watch the animation I linked to?

This is the information age, after all. Novices have a lot of info at their disposal, I don't think anyone has an excuse to be baffled any more.

 

[Thomas_81]

That's kind of like saying, "this car can't turn left, but that's completely irrelevant, given how most people drive straight."

So, try not to view handguns as though they were top-fuel drag cars -- assuming that "most owners" want to go 300 mph, 1/4 mile at a time.

lol.

I get all that, perhaps that wasn't the best way to describe what I was thinking. I understand it's usefulness, and why it's important to a lot of users, my beef was really all about the information, and how it is conveyed to people with no previous experience.

 

[Thomas_81]

Did you watch the animation I linked to?

This is the information age, after all. Novices have a lot of info at their disposal, I don't think anyone has an excuse to be baffled any more.

I did. It helped.

Thanks for posting it.

 

[Sam1911]

If I am a novice, I read this, then go out and buy a Beretta 92FS... load the magazine, rack the slide, take the safety off, and fire...Im going to be pretty confused when the first shot is not fired in Double Action.

Ok. I can see that point. But some level of self-education must be incumbent on the purchaser. The owner's manual is going to explain this. Any instructor would demonstrate this. Heck, even the expert behind the sales counter might explain this.

If the new owner does exactly what you describe, well ... wouldn't we say they aught to take some level of responsibility for understanding how a potentially deadly weapon works before they risk life and limb with it?

And if they don't bother to get that basic understanding down, on their own, what other -- much more important -- safety and operational procedures are they not familiarizing themselves with?

Heck, if they bought a 1911 instead, are we to feel bad that they don't inherently know that the thumb safety must be manually applied for it to work as designed? How different is the operation of a decocker?

 

[mgmorden]

Sam1911: Not only that, but I'd wager that if they, rather than relying on simplified forum advice - actually read the manual that comes with the gun, I'm willing to bet that it explains the function just fine.

Realistically, from a carry perspective, a DA/SA gun is going to fire DA the first shot. From a mechanical perspective, for the subsequent shots to be in SA the slide racking MUST leave the hammer cocked.

This whole discussion bears the taint of how overly litigious our society has become, and how little responsibility people want to accept. If you buy a gun, it is your responsibility if you don't have a clear understanding of how it works to either ask someone to show you how it works, or read the manual THROUGHLY before operating it. People not doing this is why we have all the locks, chamber indicators, mag disconnects, and a billion other useless gizmos added to guns when simple familiarization is all that's needed, and is STILL needed regardless of how many whiz-bang features (read: failure points) they add.

 

[rellascout]

I think the other point that is being missed by the OP is that if you are carrying a DA/SA handgun or using it for defense the quality of the DA trigger is very important. After all it is going to be the first pull if the weapon is drawn.

When I tryout or test drive DA/SA pistols I really want to test the DA pull. On all DA/SA guns I am looking for a smooth consistant DA trigger that is not too long. This is why so many reviews focus on the quality or atributes of a DA pull of a DA/SA gun.

The DA pull was what made Sigs name IMHO along with reliablity.