Among the most misunderstood action types is the selective double-action handgun. The SDA is among the best suited to some types of shooting and compliments individual shooting styles well.
It isn’t for everyone, but has proven to be a good choice for shooters who take time to understand the type.
Let’s look at a few definitions first. Single-action self-loading handguns feature a trigger that does one thing, drops the hammer or releases the striker.
The slide is racked and the pistol is cocked and ready to fire. The trigger is pressed and the pistol fires. For many years, the majority of handguns were single-action.
The Little Tom, a small pocket pistol, was among the first double-action handguns. This handgun used the trigger action to both cock and drop the hammer.
The trigger is pressed and a trigger bar moves the hammer to the rear. The hammer trips the sear and drops, firing the handgun.
In a double-action-only handgun like the Little Tom, the action is the same for every shot. The SIG P250 is another example. A double-action first shot pistol operates differently.
The trigger presses the trigger bar and the hammer is cocked, trips and fires.
The slide recoils, but the difference between the double-action-only handgun and the double-action first shot handgun is that the double-action first shot handgun is double-action for the first shot.
Then the slide recoils and cocks the hammer for subsequent single-action fire.
How Selective Double Action Works
When the double-action first-shot handgun is loaded, there must be some means of lowering the hammer safely. The trigger may be pressed as the hammer is held and safely lowered to the ready position.
The selective double-action self-loader is another variation. Early versions of the Beretta 92 were selective double action. They featured a frame-mounted safety that made cocked-and-locked carry possible.
The Taurus PT92 was patterned after the early Beretta 92 and built on machinery originally intended to fulfill a military contract for the Beretta, so it made sense to not redesign the pistol.
Later, Taurus retained the selective double-action feature, but added a decocker. The original CZ 75 and most present versions are selective double action.
(The CZ 75 has been produced in DAO and decocker versions as well.)
A selective double-action pistol operates much like a single-action pistol. The handgun is loaded and then the hammer must be manually lowered by pressing the trigger as the thumb lowers the hammer.
A long press on the trigger cocks and drops the hammer. After the pistol fires, the hammer is cocked by the slide and subsequent shots are fired in single-action mode.
This is where things are both interesting and different.
Italian police asked for a decocker version and that is the Beretta 92 that was adopted by the U.S. Army. The Czech military kept the original selective double-action CZ 75.
The term selective double action is used because the pistol may be fired either double-action first shot or single if carried cocked-and-locked.
Most double-action first shot pistols may be fired by simply cocking the hammer for a single-action shot if preferred.
This allows for more options. However, for those that prefer a double-action first-shot pistol, I believe that the selective double-action pistol offers a tactical advantage over any pistol with a slide-mounted decocker.
The greatest advantage may be that the safety of the CZ 75 pistol is frame-mounted and much more ergonomic than any slide-mounted safety.
Advantages of Selective Double Action
The advantage is in tactical movement.
Once you have worked through the double-action trigger press and the pistol is firing in single-action mode, you do not have to decock the action as you would with a decocker-type pistol to make the handgun safe, hammer down, for movement.
To make the pistol safe during movement, simply place the safety on. When you wish to fire again, you need only thumb the safety to the on position and you have a crisp single-action trigger.
With the decocker-type handgun, to make the piece safe during movement, you would have to decock and then work through the long double-action trigger again to fire.
Most shooters do not like doing tactical movement with a cocked pistol in the single-action mode.
The choices are there. For most civilians, the decocker-equipped CZ pistols such as the P-01 may be the better choice for general handling.
For those wishing to own a pistol with good shooting attributes — but who do not wish to deploy a single-action pistol — the selective double-action pistol has much to recommend.
As an example, the single-action 1911-type handguns must be carried cocked-and-locked for speed to an accurate first shot.
For home ready, most of us will lower the hammer and keep the piece ready in this manner, requiring the hammer to be cocked before firing.
With the SDA-types, the pistol may be at home ready and be fired simply with a first shot double-action trigger press.
The original CZ 75 did not allow the option of hammer down and safety on, the safety could only be applied with the hammer to the rear.
A modern variation on the SIG P-Series design is the Arex Rex Zero 1. Many experienced shooters find this pistol is an improvement over the original SIG P220.
The decocker also serves as a slide release. This is important, as shooters often ride their thumb on the SIG slide lock during firing. The result is the pistol does not lock open on the last shot.
Moving the slide lock to the decocker lever offers rapid manipulation. Arex also added a manual safety. This safety may be applied when the hammer is down.
The Arex Rex Zero 1’s safety may also be applied when the hammer is cocked. This makes for among the most attractive selective double-action pistols available.
Another desirable selective double-action handgun is the Beretta Tomcat. The pistol features a double-action first shot trigger.
The safety may be placed in the on position when the hammer is down or when the hammer is cocked. A great advantage of the Tomcat is that the slide doesn’t have to be racked to load the chamber.
A tip-up barrel makes loading simple. This combination of features makes the Tomcat a superior pocket pistol in many ways, but it is also a pistol that demands attention to its unique manual of arms.
Selective double action is useful, but it must be practiced.
Selective double action is one choice among many. Whether it is the first choice or the last choice for the individual is up to personal preference.
What do you think of selective double action? What’s your favorite SDA pistol? Let us know in the comments below.