Single Action vs. Single Action Only

[jsharmon7]

Is there a difference between SA and SAO? I recently read the "Triggernometry" article in the NRA magazine and it explained the differences in types of triggers. Unless I read the article wrong, it seemed to imply that there was a difference between SA and SAO. If SA means simply that the trigger only releases the hammer, what does SAO do? Did I read the article wrong maybe and they are the same thing?

[shooter521]

Originally Posted by jsharmon7

Is there a difference between SA and SAO?

IMO, when a gun is referred to as "a single-action," as in a 1911 or Colt Peacemaker, that to me implies SAO.

If you're talking about the trigger mechanism or pull itself, then "single-action" could be distinct from SAO, since traditional double-action guns can also be fired single-action.

Clear as mud? Personally, I don't hear/see the term SAO used much.

[jsharmon7]

Originally Posted by shooter521

IMO, when a gun is referred to as "a single-action," as in a 1911 or Colt Peacemaker, that to me implies SAO.

If you're talking about the trigger mechanism or pull itself, then "single-action" could be distinct from SAO, since traditional double-action guns can also be fired single-action.

Clear as mud? Personally, I don't hear/see the term SAO used much.

So you think maybe single action could refer to a gun that has both capabilities?

Here is a link to the PDF article for anyone who hasn't read it:

http://americanrifleman.com/Webconte...andguntrig.pdf

[shooter521]

Originally Posted by jsharmon7

So you think maybe single action could refer to a gun that has both capabilities?

No; by definition, that gun would be double action (DA or DA/SA). What I'm saying is that if you're talking about a "single-action trigger," it could be on a DA/SA or an SA (SAO) gun.

from the article:
If you stick to basic definitions, that is logical terminology. Double-action means a trigger system in which pressure on the trigger performs two functions: fully cocks or fully loads the hammer; then releases it to fire the gun. Since there may or may not also be a single-action-trigger function on the same gun, using double-action-only simply clarifies the description of the pistol. Double-action-only means that double-action is the only way to fire the gun. Some companies have also gone to the single-action-only (SAO) terminology to describe a trigger system that requires some other force to cock the hammer and trigger pressure has the sole function of firing. The current abbreviations of DA, DAO, SA and SAO are all accurate descriptions.

My read is that they are not implying that SA and SAO are any different in terms of definition, only that some companies are using the term SAO to distinguish a single-action only trigger or gun from the single-action function of a DA/SA trigger. IMO, they are trying to eliminate confusion, when in the end they are just further complicating matters.

I use the terminonlogy "traditional double-action" (DA/SA) when referring to a gun that can be fired in either double or single action mode. I use "single action" (SA) when referring to a gun that can only be fired single-action. I use "double-action only" (DAO) when referring to a gun that can only be fired double-action. I don't see the need for "SAO".

[jsharmon7]

Originally Posted by shooter521

My read is that they are not implying that SA and SAO are any different in terms of definition, only that some companies are using the term SAO to distinguish a single-action only trigger or gun from the single-action function of a DA/SA trigger. IMO, they are trying to eliminate confusion, when in the end they are just further complicating matters.

I use the terminonlogy "traditional double-action" (DA/SA) when referring to a gun that can be fired in either double or single action mode. I use "single action" (SA) when referring to a gun that can only be fired single-action. I use "double-action only" (DAO) when referring to a gun that can only be fired double-action. I don't see the need for "SAO".

Gotcha. Thanks, will add rep when able!

[Coach]

Originally Posted by shooter521

I don't see the need for "SAO".

I agree 100%.

[gund]

There's also SA/DA. Different from DA/SA.

A description by someone else:

SA/DA: Found in Taurus' model pistols, this set-up maintains a "cocked" firing pin whenever the chamber is loaded. However, if the primer of the chambered cartridge fails to ignite upon firing, the trigger releases to a heaver double-action (DA) pull, allowing the shooter an opportunity to re-attempt firing the same cartridge before manually racking the slide to eject the malfunctioning round and chamber a fresh one. Newer SA/DA Taurus pistols also have a "decocker" incorporated into the manual safety, either allowing "cocked and locked" carry when the manual safety is set to "Safe", or "uncocked and locked" carry when the manual safety is pushed upwards past the "Safe" position to decock the firing pin. (On models with decocker safeties, a red "Firing Pin Status" incidator will appear at the back of the slide to denote a "cocked" status.)

In practice the distinctions gets blurred. I think glocks the striker travels back a little before being released. So some say SAO, some say DAO. It's half-cocked when chambering. You can't manually decock.

I prefer the term SAO to SA. Provides more information and less confusion.