Double Action and Single Action Only - Am I correct?

[Ned]

Good day:

I have what I know is a VERY basic question but I'm trying to get my terms clear (to myself).

For any semi-auto pistol does "Single Action Only" mean the pistol will cycle and recock after being fired but the shooter cannot manually cock the piece and, conversely, does "Double Action" mean it could be manually cocked in addition to the normal cycling action?

Thank you.

Ned (who currently only has revolvers)

[Keith L]

I had a Smith 4506 that had a decocking lever.  If the hammer was decocked the pistol would double action with the trigger just like a double action revolver.  After the first shot the hammer was cocked and it had a mile of free play before getting to the business end of the sear.  I understand some autos are always double action, and some are double/single like my 4506. 

[KansasPaul]

Hi Ned,

Not sure if you got your question answered,  but here is my input:

Single action: The hammer must be moved into the cocked position by moving the slide back (to chamber a round) or if a round had already been chambered by manually moving the hammer back into the cocked position - much like pulling back the hammer on a single action revolver such as a Ruger Blackhawk or Colt Peacemaker.  My S&W 1911 must have the hammer manually moved to the cocked position in order to fire a round.

Double action: A squeeze of the trigger will move the hammer from the decocked position through the cocking cycle and firing cycle. The hammer would not have to be moved manually before firing. Some pistols such as the KelTeK 3PAT are double action only - there is no external hammer and the gun is fired by squeezing the trigger.  My S&W 4006 can be fired in single action, by staging (cocking) the external hammer and squeezing the trigger - or by double action, having the hammer decocked, and firing the pistol by squeezing the trigger from the lowered hammer position.

Double action will always have a heavier trigger pull than single action because the trigger pull has to overcome the spring pressure against the hammer which must travel through the entire firing cycle.

I hope that this helps.

Paul

[Ned]

Paul:

Thank you for your reply.

My interest is Bullseye shooting so it would appear a SA pistol might be better since it would have a lighter trigger pull(?)

Ned

[GatCat]

Yes, you are correct, for Bullseye shooting, a single action would give a lighter trigger pull for the first shot.
Then, to slightly confuse matters, there is the "Glock" type trigger, which is like a single action, same pull every shot, and the trigger pull can be made quite light ( Glock, Springfield XD's ). Those, I think, are neither correctly called a single action, nor a double action.
Mark

[mdi]

Not including the striker fired guns, the first round on a single action the hammer must be manually moved to the full cock position. Either by racking the slide or cocking the hammer. On a double action, the hammer is moved from the "down" position all the way through the firing cycle with the trigger, then the second round is fired "single action" after the slide cocks the hammer. A round must be in the chamber for both types of triggers/actions.

[SHOOTALL]

lets muddy the waters , SA you cock it to fire it with the slide movement or thumbing back the hammer.
SADA you fire it by pulling the trigger to cock and fire the first round then it fires as a normal SA then a decocker may be used to decock in most cases.
Then there is the DAO which fires each shot in DA mode . Then you have The Glock hybrid DA . And then there is the LDA - light DA which other than a SA gun is the next best IMHO.

So in reality the DA covers alot of ground in an effort to circumvent learning the manual of arms for a SA hand gun and being safe with it .

[KansasPaul]

Well gents we certainly managed to make the "waters" murky for Ned....

I like the single action for bullseye competition but GatCat has a point about Glock pistols.  Personally I am not a huge fan of Glocks but I know plenty of people who love them. For me it's about the ergonomics, I'm not hip on the way they fit my hand. I much prefer a 1911 or CZ P01.  Anyway, one thing to consider with the Glock platform is that the connector can be swapped out which improves trigger pull (more crisp) and lighten the pull at the same time. New connectors cost about $10.00 from Midway.  You can do a google search for Glock connector for more info.  Also, if you do think about a Glock, do a search for "Glock World" - all models are listed there as well as upgrades.

Paul

[williamlayton]

Single action would indicate that there was/is only one way to shoot it.
Double action indicates there was/is two ways to shoot it.
S/A can have two ways to shoot it but only one way with the particular gun in question.
I understand and am getting a headache.
Blessings

[LabRat2k3]

Double action/single action referes to how many actions the trigger performs. In a double action when the trigger is pulled it first moves the firing device, be it hammer or striker, to the cocked position (action one) then releases the firing device from the cocked position(action two). On a single action the trigger only releases the firing device from the cocked position. Since Glocks have been brought up lets talk about them too. They are a "safe-action", which is still a variation of a double action, the firing device is partially cocked by the rearward movement of the slide, then when the trigger is pulled it completes the cocking and releasing of the firing device. XD's while they look simular to Glocks are however a single action due to the fact that they are fully cocked by the slide movement and the trigger only releases the striker. Too many people want to talk about hammer this and hammer that when the terms are referring to the trigger not the hammer.

[SHOOTALL]

Gee the Glock course I took said the Glock action was partialy cocked and the trigger movement completed it . They stated it was nither SA or DA but a hybrid action often classed with DA in competition .

[LabRat2k3]

That is correct, that is what I said. Glocks are a hybrid of the two, called "safe action", but are considered a double action in some circles due to the fact that the trigger still completes two actions when it is pulled. The XD's are a single action. After re-reading my last post I think that my poor punctuation in the sentance about XD's may have made it seem like I was saying that Glocks were single action.

[coyotejoe]

Just get a revolver, then there is no confusion about single action or double action. Well-- there are a few revolvers which are double action only. 

[SHOOTALL]

and many that are SA only and alot that can be shot both ways .

[KansasPaul]

...........you guys are killing me.    We've managed A/SA "horse" until it's glue. That said, I can honestly say that I thoroughly enjoy the banter.

Paul

[coyotejoe]

and many that are SA only and alot that can be shot both ways .

I used to think "double action" meant it could be fired two ways, by cocking the hammer or by just pulling the trigger but then came "double action only". Actually one of the very first double action revolvers, the British Adams cap & ball was DAO so I guess it never has been that simple.

[1911crazy]

SA;  You need to chamber it and to have it cocked to fire the first round, then its a semi auto after the first round is fired.  (like my 1911's)

DA;  You just chamber it and lower the hammer, then pull the trigger to fire it, then its a semi auto after its fired. (double action on the first shot like my CZ pistols)  On my CZ's there is no way the hammer can fire it once its lowered with a round in the chamber unless you cock it and pull the trigger or use the trigger(DA).

I personally like the double action on the first shot in pistols mainly because its a safer way to carry it(CCW).

[mrussel]

Hi Ned,

Not sure if you got your question answered,  but here is my input:

Single action: The hammer must be moved into the cocked position by moving the slide back (to chamber a round) or if a round had already been chambered by manually moving the hammer back into the cocked position - much like pulling back the hammer on a single action revolver such as a Ruger Blackhawk or Colt Peacemaker.  My S&W 1911 must have the hammer manually moved to the cocked position in order to fire a round.

Double action: A squeeze of the trigger will move the hammer from the decocked position through the cocking cycle and firing cycle. The hammer would not have to be moved manually before firing. Some pistols such as the KelTeK 3PAT are double action only - there is no external hammer and the gun is fired by squeezing the trigger.  My S&W 4006 can be fired in single action, by staging (cocking) the external hammer and squeezing the trigger - or by double action, having the hammer decocked, and firing the pistol by squeezing the trigger from the lowered hammer position.

Double action will always have a heavier trigger pull than single action because the trigger pull has to overcome the spring pressure against the hammer which must travel through the entire firing cycle.

I hope that this helps.

Paul

 Ive never owned a double action only pistol,but my understanding of it is,the weapon will never fire single action. On a double action,the motion of the slide resets the hammer to the cocked position so only the first shot is double action,all subsequent shots are single action. The double action only however does not do that. Each shot is double action becuase the motion of the slide loads a new round but does not cock the hammer.(or internal striker)

 Internal hammers or strikers can be found on single or double action weapons. I have a MAB Model D which is a French 32 that is a single action. It has an internal striker. To operate it,you place magazine in the empty gun and rack the slide. That loads a round and cocks the striker. There is no way to get a round into the chamber without cocking the weapon and there is no way to decock the weapon without pulling the trigger. I would never carry that one becuase the only thing that keeps the striker held in place is a little tab on the sear. If dropped Im not convinced it would not fire. What it needs is a piece that blocks the striker when the safety is on.

[Keith L]

How many ways can we say the same thing...

[mdi]

How many ways can we say the same thing...

So far it looks like about 16!

[SHOOTALL]

about half as many ways as we hear it 

[1911crazy]

Since some brought it up how often do you really shoot a double action revolver in double action??  I know i'm not alone in this very bad habit of shooting the double action in single action only with the first shot.  After saying this and thinking about my safety if i ever shoot a revolver in double action can i actually hit my target.  Heck i have a bad habit
with my double action auto's too.  Thanks for the wake up call.  Its not that i never shot any of them in double action but i should practice more with them both.  We need to be on top of our game if the situation ever arises.

Thank God I only ever pulled my 357mag once on an addict but the sight of the gun sent him out of my sight for eons.  Something was said to me that he should of thought twice about saying it.  I told him i'd shove this 6" barrel up his butt and pull the trigger.(70's)  I've learned gun control since then.

[SHOOTALL]

every time i shoot the 340 PD its DAO .

[Keith L]

Each mode has its place.  I sold my 4506 because I hated all the travel in the trigger to get it to work double action.  I bought a Kimber with a primo trigger to take its place.  For carry I have a Glock with an equally crappy trigger, but it will be there for me without having to think much about it if it is needed.  My groups are a bunch better with the Kimber...

[1911crazy]

In a bad situation there maybe not time to pull the hammer back so double action is the way to go.  With two hands you can't miss but with one hand i would aim a tad lower because the pistol will come up slightly when double action is used. I've seen the crap happen so fast you will never know your doing it, your body / mind just does it.  Its the same as hunting your mind knows what to do.

[Keith L]

In a bad situation there maybe not time to pull the hammer back so double action is the way to go.  With two hands you can't miss but with one hand i would aim a tad lower because the pistol will come up slightly when double action is used. I've seen the crap happen so fast you will never know your doing it, your body / mind just does it.  Its the same as hunting your mind knows what to do.

A personal defense situation needs to happen with muscle memory.  If you have to think it through you are done.  There won't be enough time.  My weapon needs to be locked and loaded. 

[KansasPaul]

...personal defense needs combined with lack of firearm control is the reason why Taurus has sold a boat load of it's "Judge" revolver which fires .410 shot shells.  Five or six rounds of no. 6 can be shot with eyes closed and you can still hit a potential target...in double action or single action.

..... I think we've digressed from the original post.

Paul

[Mikey]

"..... I think we've digressed from the original post."  I agree even though this has been interesting.  I'm a bit surprised at myself when I think about how to answer the original question posed by a revolver guy about different types of semi-auto actions and it certainly can get confusing but we have enjoyed some good answers. 

Now, the real question is:  Did Ned get the answer he wanted to his 'very basic question'  Stay tuned for the next episode of 'SA/DA Confusion', or is it The real question behind the 'Full Time or Part Time Trigger Roll' (sounds from the Dragnet theme inna background)...................

[mrussel]

...personal defense needs combined with lack of firearm control is the reason why Taurus has sold a boat load of it's "Judge" revolver which fires .410 shot shells.  Five or six rounds of no. 6 can be shot with eyes closed and you can still hit a potential target...in double action or single action.

..... I think we've digressed from the original post.

Paul

 But thats only when you have a 3" barrel. Still,I bet someone who has the proper "skills" could still miss if he tried hard enough.

[mcwoodduck]

Single action- Hammer must be back before the trigger is pulled.
Double action- the hammer can be set or the trigger will set the hammer.  
Double action only- the trigger is the same for every round and the hammer does not stay back.  Every pull of the trigger will have the hammer strike.
Striker Action- more single action than anything else.