What are the different handgun actions?

If someone hands you a handgun and says "it's single action," that means something specific about how the gun works. Not what caliber it is. Not how many rounds it holds. How the trigger connects to the thing that fires the bullet.

That mechanism is the action.

Getting it wrong doesn't mean you can't shoot the gun. But understanding it changes how you train, how you carry, and what to expect when your hands are shaking and your heart rate is at 160.

What does "action" actually mean?

The action is the mechanical system that cycles a firearm. Pull the trigger, and the action handles cocking (or confirming the gun is already cocked), releasing the firing mechanism, and in semi-autos, cycling the slide to chamber the next round.

Different actions handle the "cocking" part differently. Some require you to do it manually. Some do it for you, at the cost of a heavier pull. Some split the difference.

That's the whole conversation.

What is single action (SA)?

Single action means the trigger does exactly one thing: it releases a hammer that's already cocked.

You cock the hammer manually, or the slide cycling after a shot does it for you. The trigger pull is short and light, typically 3.5 to 5 pounds. That light pull is why competitive shooters love SA pistols. Less force, less movement, tighter groups.

The tradeoff is that you're carrying a cocked hammer. That requires a mechanical safety you have to deliberately disengage before firing. On a Colt 1911, you get both a thumb safety and a grip safety. On a Browning Hi Power, just the thumb safety. You have to train those safeties until working them is automatic, because a moment of hesitation costs you time, and forgetting costs you far worse.

SA pistols reward patience and training investment. If you're interested in target shooting or competition, they're worth learning. For a first defensive carry gun, most instructors steer beginners elsewhere.

What is double action (DA)?

Double action means the trigger does two things: it cocks the hammer and releases it in a single pull.

The pull is long and heavy, typically 7 to 12 pounds or more. You're doing mechanical work with your finger that an SA shooter already did manually. That weight is intentional. A gun that requires 10 pounds of deliberate pressure to fire is less likely to fire by accident than one that requires 4.

This is why many law enforcement agencies issued DA revolvers and DA pistols for decades. The heavy pull acts as a passive safety layer. No manual safety to remember. No selector to flip. Squeeze hard and it fires, or it doesn't.

The cost is accuracy. A heavier, longer pull is harder to execute without disturbing the sights, and that's not controversial.

What you should be careful with is the widely repeated claim that this explains the gap between agencies' hit rates. You'll see a comparison of NYPD's roughly 15% street hit rate against the LA County Sheriff's roughly 51%, attributed to trigger weight. We went looking for the source of that comparison and couldn't find one — no original publication, no attached years, and the two numbers appear to use different denominators (rounds fired versus incidents). We're not repeating it.

Here's what is documented. In 2021 NYPD moved new recruits from its longstanding ~12-pound trigger to a roughly 5-pound one after an internal range test; across 457 recruits, average qualification scores rose about five points. That's a real effect in the expected direction — and it's a five-point gain on static paper targets, not evidence that trigger weight explains combat accuracy. Training, distance, lighting, movement, and tactics all swamp it.

Double action only (DAO) is a variant where every pull is double action. No single action mode, no hammer to cock manually. Consistent pull weight from first round to last. Some people find that consistency easier to train around than the transition you'll read about in the next section.

What is DA/SA (traditional double action)?

DA/SA is a hybrid. The first shot fires double action, heavy and long. Every shot after that fires single action, light and short, because the cycling slide re-cocks the hammer automatically.

The argument for this setup: the heavy first pull on a loaded, chambered gun provides a safety margin before you've committed to firing. Once you're in the fight, the lighter SA pulls give you better accuracy on follow-up shots.

The argument against: you have to train two different trigger motions. That transition between the heavy first pull and the lighter follow-up is where newer shooters stumble. Your muscle memory for the second shot assumes the first shot's resistance, and it isn't there. Experienced DA/SA shooters handle this without thinking. Getting to "without thinking" takes repetition.

These pistols use a decocking lever to safely lower the hammer without firing. You draw, you're in double action mode. You don't fire, you decock. Clean and safe.

The Sig P226, Beretta 92FS, and CZ 75 are the standard examples here. The Beretta M9 — the military designation for the 92F/92FS pattern — was adopted as the U.S. armed forces' standard sidearm in 1985 and served roughly three decades before the Army began replacing it in 2017 with the M17 and M18, SIG P320 variants chosen under the Modular Handgun System program. The P226 saw serious competition use and military adoption worldwide. The learning curve is real, but it's manageable.

What is striker-fired?

Striker-fired pistols have no external hammer. Instead, a spring-loaded firing pin (the striker) sits inside the slide, partially compressed, held back by a sear. When you pull the trigger, the sear releases the striker, it flies forward, hits the primer, gun fires.

Pull weight on most factory striker-fired duty and carry pistols runs 5 to 6.5 pounds — Glock specs the Gen5 G17 at 26 newtons, about 5.8 pounds. Agency-specified heavy triggers like NYPD's old NY-2 can reach 8 pounds or beyond, but those are a special order, not the norm. Whatever the weight, it's the same pull every time: no first-shot/follow-up transition, no external hammer to snag on clothing, and no manual safety on most models.

Instead of a manual safety, striker-fired pistols rely on a stack of passive internal mechanisms: a firing pin block that physically obstructs the striker until the trigger is pressed, a trigger safety tab that prevents the trigger from moving unless your finger is positioned correctly, and a drop safety that prevents the gun from firing if it falls. These engage and disengage automatically. You don't manage them.

Striker-fired pistols dominate the current market for exactly these reasons. The Glock 17 and the Smith and Wesson M&P are the platforms most new shooters encounter first. Consistent trigger feel, no manual safety to forget, reliable function, and a design that's been refined over 40 years of real-world use.

One detail worth knowing: not all striker-fired actions are identical. Glock pistols are partially pre-cocked when chambered, with the trigger completing the cocking cycle. The Sig P320 is fully pre-cocked. The distinction affects feel and some safety considerations, but for most shooters it doesn't change the day-to-day experience.

How the trigger press actually works

Every trigger pull has stages. Understanding them helps you diagnose why your shots go where they go.

Pre-travel (also called slack or take-up) is the initial movement before you feel resistance. The wall is where that resistance starts. Creep is any additional travel after the wall before the gun fires. The break is the shot itself. Over-travel is movement after the shot. Reset is how far forward your finger must travel before the action is ready to fire again.

A long, heavy pull on a light gun is a physics problem. A 12-pound pull on a pistol that weighs 2.5 pounds unloaded generates enough torque to move your sights before the shot breaks. That's not you being bad at shooting. That's mechanics. Lighter, shorter pulls are easier to manage accurately because there's less time and force working against your sight picture.

Dry fire training matters here too. You can work the entire trigger press, build muscle memory for the reset, and diagnose your own flinch pattern without live ammunition.

What are the internal safety mechanisms?

Most modern handguns have several passive safeties built in.

A firing pin block is a physical barrier inside the slide that prevents the striker or firing pin from moving forward unless the trigger is pressed. Drop it, bump it, the block holds.

A transfer bar (common in revolvers) works similarly, physically connecting the trigger mechanism to the firing pin only at the moment of firing.

These mechanisms are always on. You don't control them, and they reset automatically after every shot. A firing pin block stops the striker or firing pin from reaching the primer unless the trigger is pulled, which is why modern pistols don't discharge from a dropped-striker impact.

It is not a blanket guarantee against drop-fire, and there's an instructive counterexample. Pre-2017 SIG P320 pistols passed standard drop tests but could discharge when dropped at certain angles — not because the firing pin block failed, but because the mass of the trigger swung rearward on impact, completing the trigger stroke, which lifts the block. The safety worked exactly as designed and the gun fired anyway. SIG issued a voluntary upgrade in August 2017 lightening the trigger, sear, and striker.

The lesson generalizes: a passive safety defeats the failure mode it was designed for, not every failure mode.

This is still different from a manual safety, which you control and can forget.

The human factor

Here's the part the specs don't tell you.

Under real stress, your body does things it doesn't do at the range. Sympathetic contraction means squeezing or grabbing with one hand can drive the other hand to squeeze too — a documented interlimb effect in neuromechanics research. If something startles you and you grab a railing with your support hand, your gun hand may tighten at the same time.

It matters because the trigger finger doesn't reliably obey. In a Human Factors study using an instrumented service pistol in a realistic high-stress scenario, about 20 percent of officers put a finger on the trigger despite training and explicit instruction not to — and afterward, many denied having done it.

A heavy trigger pull (10-12 pounds) will prevent some of those unintentional discharges. It will also cause some misses that a lighter trigger wouldn't. There is no setup that eliminates human error completely.

What actually reduces accidents and improves performance is training. Trigger discipline, situational awareness, holster safety, and repetition. The action type is a variable. Your training is the constant.

Comparing common platforms

Holster considerations by action type

Your action type changes what holster works and how you use it.

Kydex holsters retain the gun at a consistent level and physically protect the trigger guard. Leather holsters can deform over time, which matters because a deformed holster can press on a trigger. For everyday carry, Kydex is the right call.

For appendix carry (AIWB), a rigid holster with solid trigger guard coverage is non-negotiable. Reholstering should be slow and deliberate, visually confirmed. The gun goes in the holster before the holster goes on your body. No exceptions.

Some striker-fired shooters use a striker control device, a small lever that gives tactile feedback during the reholster, similar to what a visible hammer provides on a DA/SA or SA pistol. It's not required, but some people find it adds confidence.

Which action should you choose?

New shooter, no strong preference: a striker-fired pistol. Consistent trigger pull, no external hammer to manage, passive safeties, and a huge selection of training resources, holsters, and aftermarket support. The Glock 17 and the M&P 2.0 are both solid starting points.

Accuracy focus or competition interest: single action is worth the training investment. The 1911 platform has a learning curve and requires more maintenance discipline, but the trigger is genuinely excellent.

Defensive carry, some prior experience: DA/SA works well if you train the transition deliberately. The Sig P226 and Beretta 92FS have decades of field use behind them. If the DA/SA transition doesn't appeal to you, a striker-fired gun gets you similar capability with a simpler manual of arms.

What matters more than which action you pick is whether you train with it. A Glock that someone practices with twice a week will outperform a 1911 that lives in a drawer. Consistency, repetition, and knowing your gun under pressure. That's the real variable.

Pick the action that makes you most likely to train. Then train.

Frequently asked questions

What are the different types of handgun actions?

Four you'll actually encounter. Single action (SA): the trigger only releases an already-cocked hammer, so the pull is light and short. Double action (DA): the trigger both cocks and releases, so it's long and heavy. DA/SA: heavy first shot, lighter follow-ups as the slide re-cocks the hammer. Striker-fired: no external hammer, a spring-loaded firing pin held by a sear, and the same pull every time.

Which handgun action is best for a beginner?

Striker-fired, for most people. The trigger feels the same on every shot, there's no external hammer to manage, no manual safety to forget, and the selection of holsters, training, and aftermarket parts is enormous. The Glock 17 and the M&P 2.0 are both reasonable starting points.

Is a heavier trigger safer?

Partly, and it costs you something. A heavier pull does make an unintentional discharge less likely — that's why agencies issued 10-to-12-pound triggers for decades. It also makes the gun harder to shoot accurately. When NYPD tested a lighter trigger with 457 recruits in 2021, average qualification scores rose about five points. There's no setup that eliminates human error; training does more than trigger weight.

Will a modern pistol fire if I drop it?

Generally no. Firing pin blocks physically stop the striker from reaching the primer unless the trigger is pulled. But it isn't absolute — pre-2017 SIG P320s could discharge when dropped at certain angles because the trigger's own mass completed the trigger stroke on impact, which lifts the block. SIG offered a voluntary upgrade in 2017.

What's the difference between Glock and SIG P320 striker systems?

Glock's slide cycle leaves the striker roughly 60–70% cocked and the trigger stroke finishes the job before releasing it. The P320's striker is fully tensioned by the slide, so the trigger essentially only releases it. It changes the feel more than the day-to-day experience.

Does my action type change what holster I need?

The requirements are the same — rigid material, full trigger guard coverage, consistent retention — but the margin for error differs. A DA/SA pistol carried hammer-down has a long heavy first pull standing between a snagged garment and a discharge. A striker-fired gun doesn't, which means your reholstering discipline has to be better, not worse.