What Is A Hammer Fired Action?

If you’re just getting into shooting, you may feel overwhelmed by all of the firearm terms thrown at you. It’s enough to intimidate anyone from the brightest of scientists to the most practical of farmers. It is my intent to help you understand what a hammer-fired pistol is and some of the different actions typically associated with them.

So, let’s dive in. I promise to make it easy to understand what a hammer fired action is and how it impacts your shooting.

Firearm Actions

We all understand the general meaning of the word action: to do something. When you perform an action, you are doing something. While more specialized a term in the gun world, a firearm action is not terribly dissimilar.

When we are talking about guns, an action is a noun – a thing. A gun’s action is the assemblage of parts that allow you to chamber a live round, fire it and to remove the empty cartridge case.

There are many kinds of actions. For example, the popular lever action rifle uses a looped piece of metal beneath the gun’s body. When you lever, or move, that metal downward, the firearm opens and ejects a spent case (if present.) When you return the lever to its starting position, a new round of ammo is moved into the gun’s chamber and the receiver closes. This process also prepares the gun so that when you pull the trigger, the gun will fire.

In handguns, we most often see semi-automatic and revolver actions. Both kinds of handguns can use a hammer system to fire the weapon.

So Why A Hammer Fired Action? 

SA/DA Hammer fired SIG SAUER pistol on a black backgroundEvery firearm that uses a modern cartridge needs to have some kind of mechanical system to fire the ammunition. This usually means a firing pin needs to strike the primer on a round. When struck, the primer ignites the powder in the cartridge case and pushes the bullet down the barrel. This system is a component of the gun’s action.

For handguns, the mechanical system is most frequently a hammer-fired system or a striker-fired one. While I am describing the hammer-fired system, you can also read Paul Carlson’s excellent article What is a Striker-Fired Action for additional information on those guns.

In a hammer-fired handgun, there is a metal part that typically moves in an arc when the trigger is pulled. When you pull the trigger and the hammer swings forward, it will strike a firing pin which then hits the ammunition primer. Some hammers will have the firing pin attached to it while many guns use a separate firing pin.

If you think of swinging a hammer to strike a nail, you have a pretty good image of how the hammer in a gun works. 

Types of Hammer Fired Pistols

In general, there are three varieties of hammer-fired pistols:

  1. Single action (SA)
  2. Double action only (DAO)
  3. Double action/single action (DA/SA)

Let me explain what each of these means.

Single Action

A single action handgun means that the hammer is mechanically cocked before the trigger will fire the firearm. The cocking can be done by hand or through an action of the pistol. A semi-automatic pistol could harness some of the rearward energy of the slide movement, for example, to cock the hammer for a subsequent shot. 

On a single action revolver, you can simply thumb back the hammer like you may have seen in a cowboy movie. That will rotate the cylinder to a new round of ammunition and lock the hammer into position. All you have to do now is pull the trigger. To fire again, you would thumb the hammer back, repeating the process.

The author pulling the trigger on a Hammer-fired Colt 1911With a pistol like the Colt 1911, you can pull the slide to the rear and release it. This will both load a round of ammunition from the magazine into the gun’s chamber and lock the hammer in the rearward position. Like the single action revolver above, all you have to do is pull the trigger and the gun will fire. Unlike the revolver, the gun will use some of the energy created when the round is fired to move the slide back, chamber a round and cock the hammer without needing additional input.

Single action guns tend to have triggers that require less strength to pull than double action guns. You may hear people refer to the triggers as being lighter as trigger pull is typically measured in pounds. Likewise, these triggers generally have a shorter travel distance. These factors can improve a shooter’s accuracy as there is less hand movement during the shooting process.

Double Action Only (DAO)

With double action only guns, all of the hammer movement is controlled by the trigger. As you pull the trigger back, the hammer makes a corresponding rearward motion until it reaches the rearmost point. Then, the hammer will fall forward and strike the firing pin. To fire a second round, you simply release the trigger and make the same pulling motion as you did for the first shot.

Double action only guns do not allow you to lock the hammer to the rear for a lighter trigger pull. The trigger directly controls all of the hammer’s movement. For revolvers, the trigger pull also rotates the cylinder of the gun to align a new cartridge with the barrel and firing pin. In a pistol, the slide movement will eject the spent shell case and chamber a new cartridge but not cock the hammer.

As you might imagine, double action only guns tend to have longer and heavier – or harder to pull – triggers than a single action trigger. While that might sound like a bad thing, it may not be. Many trainers recommend double action only guns for self-defense as you are less likely to accidentally fire the gun under the stress of a lethal force encounter.

While the triggers tend to be heavier that doesn’t mean they are hard to pull. Many DAO guns have very smooth triggers and are very easy to shoot. 

Double Action/Single Action

You might guess that a hammer-fired double action/single action gun is a blend of the two previous actions. You’d be right.

A DA/SA pistol is one that has a long pull for the first shot like a double action only gun. However, once the gun fires, the slide cycles and sets up the subsequent shots as single action. Typically, this style of pistol will have a decocker on the side of the gun. A decocker is a lever that you can press to safely uncock the hammer and return it to double action mode.

Some trainers recommend the DA/SA style of pistol for self-defense as you get a long pull for the first shot that helps to avoid unintended discharges. However, follow up shots are lighter and for faster, more accurate shooting.

I, however, find that DA/SA pistols are much harder to become proficient with. Essentially, you are having to learn two different trigger pulls during training. This could double the amount of time you would need to become accurate with this style of handgun as compared to either a single action or double action only gun. 

Double Action Revolvers

A revolver with a hammer that you can manually cock shown.While I described double action only revolvers above, there are revolvers that can be shot as either double action or single action guns. This kind of revolver is very common and has an exposed hammer like the single action revolver. 

Unlike the SA revolver, this kind of gun is typically shot in double action mode. You simply align the sights and pull the trigger. However, you can pull the hammer back to cock it for a single action shot. Like a dedicated single action revolver, the SA trigger pull on a standard double action revolver tends to be light and short.

This style of revolver is the most common revolver in the modern world. If you’ve ever watched a cop shop from the 20th Century, you probably saw the officers carrying this style of gun. They remain popular today and are still viable defensive weapons.

Final Thoughts on Hammer Fired Actions

It was my goal to help you understand what a hammer-fired action is. Hopefully this article does that. I hate going to purchase something and having the salesman speaking a language I don’t understand. I bet you are the same way.

You might wonder if a hammer-fired action is better than a striker-fired action. In my opinion, there isn’t one that is better than the other. They are just two different designs that achieve the same result: firing a pistol.

I have a variety of firearms designed for personal protection. Some are hammer-fired and some are striker-fired. I like each of them and have no problems carrying and recommending them. If you are looking for a self-defense handgun, don’t be afraid to try both styles and see what you like best.