This Article was Previously Published in The Firearms Instructor
I’ve owned and shot a variety of handguns over the last 50 years and have acquired a nice collection of revolvers and pistols. Some time ago as I was cleaning and function checking some of my guns, it became apparent to me that the as advertised double action function of the triggers was quite different in some of the guns. While the revolvers and hammer fired semiautomatics were similar, the striker fired pistols were different in weight and length of pull. It became obvious to me that striker fired pistols should have a category of their own for trigger description separate from hammer fired pistols and revolvers as they are significantly different in feel and function.
This idea evolved into a discussion that I had with a group of my seasoned colleagues shortly after that. The conversation involved the definition and general understanding of trigger mechanisms in commonly used law enforcement handguns.
The discussion started with the definition of revolver trigger types as Double Action Only (DAO), Double Action/Single Action (DA/SA) and Single Action (SA).
We all agreed Double Action Only meant in order to fire each shot, the trigger had to cock and release the hammer or striker, thereby performing two actions. There were no other options. This corresponds to the SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute, Inc.) definition for Double Action Only.
Single Action meant the hammer or striker had to be fully cocked prior to the trigger being pulled to fire a shot. Thereby, one action was performed, simply releasing the hammer or striker, when the trigger was pulled. This corresponds to the SAAMI definition for single action.
All agreed that Double Action/Single Action revolvers have the capability of firing in either manner at the choice of the shooter.
We then directed our conversation to semiautomatic pistols. This is where the differences of opinion in the group began to surface.
It was apparent to us that hammer fired semiautomatic pistols largely follow the definitions of the revolvers. This is with perhaps the exceptions of early S&W DAOs, SIG’s DAK, H&K’s LEM and Para’s LDA (and perhaps a few others) which operate with the hammer mechanisms partially or pre-cocked to lighten the trigger pull which increases the likelihood of shooter’s success.
When we turned our attention to striker fired semiautomatics, we started to see a noticeable departure from the original definitions used to describe revolvers, and to a similar degree, hammer fired pistols. There are some significantly noticeable differences in defining what the trigger movement actually does in firing a hammer fired semiautomatic pistol as opposed to a striker fired semiautomatic pistol.
In doing an informal study we found in some striker fired pistols, the striker was not under significant tension until the trigger was pulled to cock and release it to fire the pistol. Then the trigger had to be returned to the starting position in order to fire subsequent shots with these pistols. This firing mechanism would seemingly compare to both DAO revolvers and DAO hammer fired semiautomatic pistols.
In other pistols we found that the striker was partially cocked with the trigger in its normal forward position and was fully cocked and released with the first trigger stroke. After which, depending on how the trigger was controlled (reset), the striker could be captured fully cocked for the subsequent shots or it could revert back to its original condition through a complete release of the trigger to its fully forward position. This could compare to a Double Action/Single Action or a Double Action Only hammer fired pistol, depending on how the shooter operated the trigger.
Furthering our study we discovered that some brands of striker fired pistols fired from a fully cocked striker by simply releasing the striker when the trigger was pulled. In the opinion of several of the participants, this seems to parallel the definition of a single action revolver or perhaps a single action semiautomatic pistol.
The difference of opinions in the group came as we discussed some of the striker fired semiautomatic pistols on the market referred to as Double Action Only or some other catch phrase that implies that to be the case. But in fact, many of these pistols actually come closer to single action in function than double action, specifically, if we used the conventional definitions for revolvers and hammer fired pistols. At that point we agreed to disagree on some of the finer points and ended our conversations.
Subsequently, I thought that getting some industry perspective might be helpful in clarifying the differences in opinion of my colleagues.
The following is a synopsis of what I learned in discussing my concerns with some of the companies with which I have contact.
Industry engineers and marketing professionals are constantly seeking to find ways of differentiating their products from other brands to make them more attractive to their customers than those of their competitors. Sometimes they deviate slightly from the written SAAMI definitions, which are recognized as guidelines for the industry, but which are not always as definitive as they could be. Then there are those unwritten definitions that most of us in the firearms community live by, as well as communicate with. These are all standardized and commonly accepted definitions which are relied upon to help avoid confusion when it comes to firearms. While the manufacturers’ intent, in most of these cases is well meaning, it has significant potential to create confusion, misunderstanding and misinterpretation for the gun owner or operator.
Some of the engineers that I have spoken with regarding my concerns about striker fired pistols tend to view double action as any movement against the striker which increases tension, however slight, added to the release of the striker, equates to two movements or actions to fire the pistol. Therefore, this movement is considered double action by the manufacturer’s standard. This might be a valid way of viewing the trigger function in the lab but it is distant from the understanding of the average handgun user who understands the definitions of hammer fired handguns where the hammer is visible. In striker fired handguns the striker is generally not visible making it unlikely for the average user to know what condition the striker is in when it is carried in the holster. Right or wrong it’s all in the eye of the beholder.
SAAMI, in its latest definitions of Single Action, Double Action, or Double Action Only include the striker along with the hammer movement as actuated by the trigger to function in the same manner.
In other words, when the striker is cocked and released with a pull of the trigger that movement is considered Double Action. However, when the striker is held in the fully cocked position and simply released by pulling the trigger, that, by definition, is Single Action.
The challenge, of course, is to get industry to abide by the specific definitions standardized by SAAMI as a guideline for all associated with handguns to live by and call their trigger mechanisms what they are, by definition, as opposed to sales speak.
So, why is this important to you the reader?
That question can be answered by a question.
Would you holster and regularly carry a cocked Revolver or DA/SA Pistol? Particularly one without a manual safety?
If you wouldn’t carry a revolver or a hammer fired pistol in the single action condition (cocked and locked single actions excepted because they have a mechanical safety locking the hammer in position), why would you carry a fully cocked striker fired pistol with no manual safety in the same condition?
It’s important to realize that many of the striker fired pistols sold to Law Enforcement and other armed professionals in today’s market, are by SAAMI definition, single action pistols. These guns with their short light trigger pulls, which we love to qualify with, have their down side in high stress events. Most notably being that they are too easy to discharge or when re-holstering the pistol and the retention strap, draw string on a jacket or untucked shirt tail find their way into the trigger guard causing a discharge.
Don’t be fooled by some sales or marketing hype. Field strip your striker fired pistol and look at how the striker is positioned when the slide is forward on the frame. The answer as to whether you have a Double Action Only or Single Action Pistol will be readily apparent.
Only then will you know for sure by your pistol’s mechanical operation as opposed to trigger semantics how your striker fired semiautomatic pistol trigger really works.
Then you can make the determination as to whether what you are carrying is as safe as you thought it was, or not.
