noob double or single

[mike6161]

Can anyone tell me the why some pistols are double action and some are single. I know in revolvers it’s you have to cock the hammer be for each shoot. I do not think you have to rack the slide each time do you?

Thanks

 

[Tamren]

A single action weapon is one where the hammer needs to be cocked, either manually (say with your thumb), or the slide cocks the hammer as it's racked. Or, put more simply, If the hammer isn't cocked when you pull the trigger, nothing happens.

Double action weapons have a mechanism where pulling the trigger also cocks the hammer. Or, if it's loaded, and the trigger is pulled, it's going to go BOOM!

Single action weapons have a lighter trigger pull which makes it easier to shoot accurately, the less force you put on the trigger, the less likely you are to unintentionally push the weapon off target while you're squeezing the trigger.

The downside of a light trigger pull is that it could theoretically make it easer for a negligent or accidental discharge. Also, if the hammer is cocked, it makes the weapon more susceptible to firing if it's dropped.

The upside of double action weapons is that unless the trigger is pulled, they aren't going to fire, there's never any force on the hammer that could strike the firing pin unless the trigger is being pulled.

The downside of double action weapons is that the trigger pull is a lot heavier, therefore making accuracy tricky. It's more likely that the extra force needed to squeeze the trigger can push the weapon slightly to one side or the other.

There's also pistols that fire in both single and double action. That way they can be carried around with the hammer down, which makes them safer, but after the first shot the action of the slide cycling would switch them over to single action, which makes follow-up shot easier. Another thing about DA/SA weapons is that if you get a round with a bad primer, you can squeeze the trigger again and try to get the round to fire on the 2nd strike (although in a serious situation I'd rather tap, rack, bang! then try to get a dead round to go live... ).

There's also striker based action which is a little more complicated, but essentially they're hammerless designs that function on a principle between double and single action.

Personally I prefer single action weapons as my finger is NEVER inside the trigger guard unless I'm ready to fire.

Hope this helps, and don't worry about asking questions, a favorite teacher of mine once said "There's no shame in ignorance if you're willing to correct the state, but all kinds of shame in being ignorant and not doing anything about it!"

Here's a sticky post on the Autoloader section that goes into more details, IMNSHO well worth the read .
http://www.thehighroad.org/showthread.php?t=248556

 

[Ske1etor]

Not all revolvers are single action. Some are double action. Hammer fired auto's are normally single action as the slide takes care of the hammer part and most striker fired pistols are double action. The first portion of the trigger pull causes the striker to preload and the break drops the striker.

On an auto, no you do not rack the slide after every shot. That would result in a bunch of perfectly good rounds on the ground.


I always like the saying "The only stupid question is the one you didn't ask." basically, ask everything. There is no shame in not knowing and "Knowing is half the battle".... lol

 

[mike6161]

Thanks for the help guys I have been wondering why there were single action pistols for a long time. I use to have a single action revolver and just kept thinking about how I had to cock it each time.
Think for the help

 

[jad0110]

Trigger Action

I've pulled the following from various sources around the internet. I've tweaked a bit of it, but don't claim credit for the vast majority of it. I'll often provide this and other info (especially safety info) to new shooters before I even take them to the range for the 1st time. Just to edumacate them a bit first.

Firearms utilize triggers to initiate the firing of a cartridge in the firing chamber of the weapon. This is accomplished by actuating a striking device through a combination of spring and kinetic energy operating through a firing pin to strike and ignite the primer. There are two primary types of striking mechanisms, hammers and strikers. Hammers are spring-tensioned masses of metal that pivot on a pin when released and strike a firing pin to discharge a cartridge. Strikers are, essentially, spring-loaded firing pins that travel on an axis in-line with the cartridge.

Single action (SA)
A single-action trigger performs the single action of releasing the hammer or striker. Examples of the SA trigger operated firearms are the Ruger Vaquero revolver and Colt M1911 pistol. In a revolver, the hammer must be cocked before each shot. In a semi automatic, the expanding gas from the firing of a round pushes the slide backward, cocking the gun for the next shot.

Double action (DA)
A double-action trigger performs the two functions of cocking and then releasing the hammer or striker. When applied to revolvers, the trigger also rotates the cylinder. Though this is technically a third action, it is correct to refer to the mechanism as double-action. Also, revolvers with a double-action trigger mechanism almost always retain the single action functionality, unless there is no external hammer. The hammer may be cocked and the trigger pulled. Typical DA revolvers are the Smith & Wesson 686 and Ruger GP100.

Double action only (DAO)
Double action only is similar to a DA trigger mechanism however there is no single action function. For firearms with a hammer, the hammer will return to its down position after each shot rather than staying cocked. For striker-fired pistols such as the Taurus 24/7, the striker will remain at its rest position through the entire reloading cycle. This term applies mostly to semi-automatic handguns, however the term can also apply to some revolvers such as the Taurus Model 650 and the Smith & Wesson 640 that are of a hammerless design.

Double action/single action (DA/SA)
A double action/single action firearm combines the features of both mechanisms. This term is applied only to semi-automatic handguns. The function of this trigger is identical to a DA revolver, however the firing mechanism (slide racking back and forward) automatically cocks the hammer or striker after the gun is fired the first time. This mechanism will cock and release the hammer when the hammer is in the down position but on each subsequent shot, the trigger will function as a single action. This means that the first shot is a long, heavy pull with the following pulls being lighter and shorter. Many people find this transition annoying, others don’t mind it at all. Try before you buy! Examples of this type of firearm are the Walther P22 and Ruger P90.