Educate me please, SA/DA, DAO relating to pocket pistols

[Guest motonut]

I fully understand SA & DA when it comes to revolvers, simple. However when it comes to pistols, particularly pocket pistols I'm a little fuzzy.

The Ruger LC9 is a pocket pistol that is DAO. After a round is chambered it still requires a full trigger pull to fire the pistol. Blowback/ejection then another round is chambered but again requires a full trigger pull to fire again. (trigger pull unknown, apx. 10# ??) Correct? The pistol functions no other way?

Now with the Sig 232 (SA/DA), after a round is chambered the hammer will be back and a SA trigger pull (4.5#) would be required to fire. But the Sig has a de-cocker so you can release the hammer w/out firing the pistol which will then put the gun into DA mode (10#), same as the LC9. In addition, you could then pull the hammer back and put the Sig back into SA mode again. Correct?

Am I missing anything?

[lowery100]

Sounds like you have it down.

[Guest motonut]

Yes, just typing it out helped me a lot, made me think about it a little bit. I almost didn't post it but I thought it might help someone else.

With the LC9 it's touted as a "locked-breech pistol", what does that mean?

Edited May 7, 2011 by motonut

[enfield]

Locked breech means the barrel is locked to the slide for a moment after firing, then the barrel tilts during recoil and unlocks from the slide. Most if not all pistols 9 mm and larger are locked-breech designs.

[Parrothead]

someone care to explain sig's DAK trigger while we're on the subject?

[LagerHead]

Wikipedia explains it here.

[Oh Shoot]

Then there's the (I think, unique) Taurus striker fired models with multiple strike capability, some with decocker from the lighter "single action cocked" position.

- OS

[Jonnin]

That got most of it, yes. There is also the internal/external hammer issue. For example, a 1911 is a single action, exactly like a SA revolver: you pull the hammer back before it can be fired (racking the slide pulls the hammer back each shot, however, and the gun is stored cocked with a safety, so its rare to actually pull the actual hammer on such a design). DA pistols with an external hammer are more common to hand-cock, done to avoid the heavy DA pull for the first shot (after which the slide keeps pulling the hammer back for you as you noted already). Internal hammer guns are at the mercy of using the slide or a DA pull to move the hammer back with no option to do it yourself.

Internally, the 3 basic types of autos work exactly like a revolver. The hammer is pulled back and trigger drops it, thats a SA. The trigger pulls the hammer back with leverage, then drops it, thats a DA shot (either from a DAO or a DA). Combine the 2 and its a DA gun. The striker fired stuff is a little different internally, but the basic behavior (from the user's perspective and in terms of the 3 basic types) of a glock or similar style trigger is a single action with internal hammer (recognise these by the safety button on the trigger).

Related to this, almost all DA autos have a junky trigger pull for the SA shooting, unlike most revolvers which have a very short, light pull when cocked. It is not uncommon to move the trigger several mm before the hammer falls, some of that travel spongy and doing nothing internally beyond pushing on a spring. SA semi's tend to have decent triggers but still not as good as SA revolvers. So if you have not spent the time there and buy a DA auto expecting it to be like a revolver, this can be a bit of a shock.

The 10-cent way to tell what is what from looking: almost all external hammer guns are DA unless it "looks like" a 1911. Almost all single action guns look a lot like a 1911. All striker fireds that I know of have the trigger safety and internal hammers. DAO can be difficult to spot but most have a trigger guard with room to make a very long trigger pull and have internal hammers -- its still difficult to spot a DAO vs an internal hammer DA at times. Combine this with brand names (most brands tend to stick to a type, for examle Khar is mostly DAO, beretta is mostly DA, ...) and you can make an educated guess correctly most of the time. However, if you see something you like, better to ask if you have any doubts since there are too many grey areas to be sure.

[Guest motonut]

someone care to explain sig's DAK trigger while we're on the subject?

Ah yes, thanks for asking about that too.