Between 1900 and 1985 an officer or department looking for a service handgun had a very easy time of it. Their choices consisted of a Colt, Smith & Wesson, or Ruger double-action revolver chambered for the .38 Special or .357 Magnum cartridge. And while some officers dared to suggest issuing semiauto pistols as duty guns, such radical notions were generally ignored.

But things got considerably more complex in the latter part of the 1980s. That's when American police agencies switched en masse to semiauto pistols. And that meant that agencies had to decide not just between 9mm, 10mm, .40, and .45, but also between a number of different trigger systems.

In general, before 1929 all semiauto pistols were operated with a single-action trigger mechanism. Even though these guns had some form of external safety, they were designed to be carried with an empty chamber and a round was only chambered prior to the handgun being fired. This made them less than suitable as everyday police weapons.

In 1929, Walther introduced the first practical semiauto pistol with a selective double-action/single-action trigger. This mechanism allows the first shot to be fired by a long, double-action revolver-like trigger stroke while subsequent shots are fired with a lighter single-action pull. Walther was onto something mechanically, but its lackluster .32 and .380 pistols were not popular with police on this side of the Big Pond, and, in the United States, the revolver remained the king of law enforcement sidearms.

This began to change in the early 1950s when S&W introduced its Model 39. The Model 39 was not only the first American-made pistol with a Walther-like double-action/single-action trigger system; it was also the first US-made pistol chambered for the 9mm Parabellum cartridge. Throughout the '50s, '60s, and '70s, the popularity of these pistols with military, police, and civilian shooters grew steadily and soon every major manufacturer was offering one. Double-action/single-action pistols were the original choice of most American police when they began switching to self-loading pistols. But just when the place of the double-action/single-action pistol seemed secure, a new trend arose: the striker fired "Safe Action" pistol.

The "Safe Action" pistol owes its popularity to Gaston Glock. While his revolutionary Glock 17 was most notable for its use of a polymer frame, the pistol's success was due far more to its trigger than its frame material. Firing the Safe Action pistol requires a stroke that is shorter than the traditional double-action but longer and heavier than that of a single-action pistol. Glock's multiple passive safeties also eliminated the necessity for external safety levers and provided a much simplified manual of arms. This made it much easier to train new shooters, and it was perfect for American police agencies transitioning from revolvers to semiautos. Today, most major pistol makers offer guns that use variations of the Safe Action trigger mechanism.

Now, nearly 20 years after the development of the Safe Action pistol, the latest trend in semiautos is the double-action-only trigger mechanism. This type of mechanism requires a long, revolver-like trigger pull to fire each shot, and proponents feel it is the most practical-and liability-free-type of trigger for police duty pistols.

The Competitors

It's no secret to anyone who reads firearms publications that each of these trigger mechanisms has a loyal group of supporters and that their partisanship is not only vocal but, at times, has been known to verge upon fanaticism. Each claims that its favored type of trigger is the "most practical" or "safest" for law enforcement purposes. So let's look at some of the pros and cons of each trigger action.

Single Action (SA)-allows the operator to carry the pistol in one of two modes: hammer down on an empty chamber or "cocked and locked." While the former is not conducive to getting the pistol into action quickly, fans of SA pistols claim the multiple manual and (in some cases) passive safeties make these guns as safe as their counterparts, while the short trigger stroke permits very accurate shooting. SA detractors counter that the light trigger pull increases the likelihood of an accidental discharge, and this is why many law enforcement agencies limit the use of SA pistols to highly trained tactical or SWAT units.

Double Action/Single Action (SA/DA)-allows the hammer to be carried down on a loaded chamber and the first shot to be fired by a long, double-action trigger pull while subsequent shots can be fired in single-action mode. All are fitted with some type of lever that lowers the hammer on a loaded chamber and doubles as a manual safety. This trigger mechanism is very popular with police agencies who believe that the long double-action trigger stroke lessens the chance of accidental discharge. However, advocates for other types of trigger actions complain that transitioning from a heavy DA to light SA trigger causes the first-and perhaps most important-shots to be inaccurate. They also dislike the fact that the safety/decocker lever is usually mounted on the slide and difficult to operate without moving the gun around in your hand.

Safe Action- is a striker-fired system that is partially cocked when the pistol's slide goes forward. A longish trigger stroke pulls the striker all the way to the rear and then releases it to fire the cartridge. Safe Action-type pistols usually feature several passive safeties that are disengaged as the trigger is pulled through its full stroke. Fans of Safe Action pistols claim that the simplicity of operation of these weapons, combined with their multiple safeties, make them the easiest to learn to operate safely and competently. Detractors feel that the resulting "mushy" trigger pull precludes accurate shooting and the lack of a manual safety lever is a disadvantage if the officer's gun is snatched away.[PAGEBREAK]

Double Action Only (DAO)-combines the safety and simplicity of the DA revolver with the benefits of the modern semiauto pistol. The trigger must be pulled through a long, deliberate stroke for all shots, greatly reducing-its partisans claim-the chance of accidental discharges. To make it safe all you must do (as with the Safe Action) is remove your finger from inside the trigger guard. Two types are generally encountered: those on which the trigger can be pulled multiple times (Ruger and Beretta); and those that, when they are dry fired, their slides must be retracted slightly to partially cock their hammers before they can be fired again (S&W and Kahr). The major argument against this trigger action is that the long, heavy trigger pull hinders accuracy.

The Competition

Despite supporters' claims regarding the practicality and safety of their favorite trigger mechanism, the question still remains: which one shoots the best? While I have used pistols with all four of these trigger mechanisms, I have never done a side-by-side comparison of how well they shoot. I decided to remedy that. So I assembled four 9mm sample pistols-a Browning HiPower (SA), a SiG P226 (SA/DA), a Glock 17 (Safe Action), and a Ruger KP95 (DAO)-and went to the range.

I decided that for me the best way to judge the potential of each pistol was to run it through some standardized drills to evaluate how the different trigger systems affect accuracy, ease of operation, and speed. To remove magazine capacity from the equation, each string of fire was limited to eight rounds. Also, to standardize ammunition, only Black Hills 9mm +P Parabellum ammunition loaded with 115-grain JHP bullets was used in this test.

The test consisted of targets set up at seven yards and the following drills:

• Draw pistol and fire eight slow fire rounds-"head" shots only.

• Draw pistol and fire four sets of rapid fire double taps, reholstering between each two-shot string.

• Repeat double-tap drill firing the pistol weak-handed.

• Draw pistol and fire eight rounds as fast as a flash sight picture can be acquired.

The Scorecard

So how did the four trigger actions stack up in my little test? Here are the results broken down into three categories, with the top-scorers listed first:

Accuracy: Safe Action, SA, DA/SA, DAO.
Overall Ease of Operation: Safe Action, DAO, DA/SA, SA.
Speed: Safe Action/SA (tie), DA/SA, DAO.

Because of their ease of handling and built-in safety features, my vote goes to the Safe Action triggers, with the DA/SA systems as a runner up. And while, as a long-time revolver shooter, I feel the DAO deserves serious consideration, I believe that gaining proficiency with such a pistol requires much training. As for the SA pistol, while there can be no denying it is a very effective combat handgun, it is a bit unwieldy, as you have to manipulate/engage various safety devices both before and after shooting. Consequently, I agree with those who feel it is best restricted to highly trained personnel.

But this is just my educated opinion. There is no substitute for hands-on experience. Consequently, I suggest that you or your agency try pistols with all four types of triggers and, after extensive practice, decide which system best suits your needs.

Paul Scarlata has served as an auxiliary police officer and writes for several firearms publications.