The world of firearms is defined by terms many don’t understand. Your average gun owner who owns a firearm for self-defense doesn’t need to know how it works inside and out. They just need it to work. That’s fine, but for some of us, the curiosity goes deeper. For those who research each and every feature of a firearm, we are giving you a treat. Today we are diving into the world of what single action and double action mean and how it affects your firearm.

Double Action vs. Single Action

Most categories of firearms are either defined as single or double action. Single and double action refer to what the trigger does when pulled. This is true for all types of firearms, from revolvers and automatic pistols to shotguns and rifles.

With a single-action firearm, the trigger does just that, a single action. That single action releases the hammer or striker and fires the gun.

With a double action, the trigger commits two actions when pulled. It cocks the hammer or striker and then releases the hammer or striker and fires the gun.

That’s the main difference, but there really is a little more than that that goes into these designs.

Actions and Guns

Single Action Only

Single-action-only weapons like the M1911, Browning Hi-Power, and Colt Single Action Army all use a hammer-fired design. Most single-action-only handguns are hammer fired, but not all. The latest Glock performance trigger converts the trigger mechanism to a full-cocked, single-action striker fire design.

Most rifles and shotguns utilize a single-action trigger. Double-action long guns are quite rare. Single-action weapons have a fairly light and consistent trigger, that’s often one of the main advantages of the design. However, the lightness of these trigger designs often calls for a manual safety or to carry the weapon with the hammer down.

Double Action Only

Double-action-only firearms are most commonly handguns. They are also typically hammer-fired guns, but DAO striker-fired guns have existed. DAO revolvers are also very popular and fairly common. Double-action guns have a fairly heavy and long trigger pull that can be a downside to many users.

Learning to shoot a DAO weapon can be a bit more challenging overall. DAO triggers and their weight is often seen as a safety feature to prevent negligent discharges. (However, the four rules are what prevent negligent discharges.) DAO triggers also allow the user to attempt to fire a cartridge more than once should they get a misfire.

DA/SA

DA/SA, or double-action/ single-action, is a popular option for automatic handguns. DA/SA guns promise to have the best of both worlds in their design. When the user pulls the trigger, the first shot is in double-action mode. After the weapon fires the first shot, the weapon converts to single action for a lighter trigger pull for follow-up shots.

These are typically hammer-fired guns like the CZ 75 and SIG p226, but Walther’s P99 and its many clones are examples of DA/SA striker-fired guns.

Modern Revolvers

Modern revolvers are typically defined as double action, but it bears mentioning that any revolver with an exposed hammer can be cocked into single-action mode. This requires the user to thumb back the hammer. The gun will only convert to single action if the user manually retracts the hammer. These handguns are also considered double-action/single-action.

Glocks (And Glock Clones)

Glock helped introduce the world to the polymer frame, striker-fired, semi-automatic pistol. Along the way, they popularized a partially cocked striker design. Technically the trigger is a double action. It fully cocks and releases the striker. However, the striker is already partially cocked when the slide is reciprocated.

While it is technically double-action, it offers a fairly light and consistent trimmer. This pre-tensioned system does not offer the same double strike capability of a traditional double-action either.

Which Is Better?

That is a matter of preference. For new gun owners, I typically recommend one of the many different forms of pre-tensioned strikers. Glock’s Glock 17/P80 popularized it, but S&W, SIG, Walther, and many more use the same system in their modern striker-fired guns. This offers you one single trigger to work with.

If you want a pocket carry or deep carry weapon, a DAO is tough to beat. When carried deep, you might have to have some compromises, and that long trigger pull can be comforting.

I tend to prefer a DA/SA handgun, but that’s just me. Ultimately, it’s entirely up to what you prefer. Each system is proven and reliable. They all have advantages and disadvantages, so it’s worth trying out each and deciding from there.

For more information on the nuances of double-action and single action revolvers, check out the informational at Target Barn.

For additional details on striker fired and hammer fired auto pistols, see the breakdown at The Truth About Guns.

See more of Travis’ work at Breach Bang Clear.