Clarifying Double Action Only (DAO)

posted on April 23, 2015
wiley-clapp.jpg (1)

I recently had the pleasure of writing up the new SIG Sauer P320 for American Rifleman. Somehow or another, I left a number of readers a little confused about the pistol's trigger action, and we can't have that. So let's take a quick second look at the gun and see if we can get things straightened out. 320s are striker-fired pistols, a first for SIG Sauer. The striker is spring loaded and becomes fully cocked when the slide comes all the way to the rear, either manually or when the act of firing drives it back. To fire, the shooter presses the trigger, an act that clears safeties and releases the striker. This initial trigger pull does feel a great deal like several other guns (Glock, S&W M&P) that partially pre-cock the striker and are called DAOs (for double-action-only). undefined

But the correct technical definition of DAO is a system where trigger pressure performs the twin functions of cocking and firing. Since the P320 is already cocked, the trigger can only release the striker. It would have to be more like an SAO (single-action-only) trigger. It would probably be better to say that DA and SA are terms that define trigger action as it relates to the pistol's lockwork. Leave the clearing of passive safeties out of the equation, even though they make some of these trigger systems feel very DA-like. Somehow, the term DAO has come to be associated with greater safety in handling, so it is unlikely that the makers will cease using it on guns that are clearly fully cocked. undefined

It is also interesting to note that proper use of the reset point in the trigger can be so very useful. For the first shot in a series, the shooter has to sweep the trigger through a longer arc to get it in position to make that important release of the striker and fire. With practice, after firing the shot, he learns to allow the trigger to return only the short distance to where it resets the striker for firing. If he needs a second shot, he now moves the trigger back the same distance and it fires again. Like the old joke, repeat if necessary. There is usually a major difference in the length of trigger travel from all the way down to trigger travel from reset.

I hope this helps, but I am betting we haven't heard the end of the subject.


Browning Xbolt Target Max Gotw 5
Browning Xbolt Target Max Gotw 5

Gun Of The Week: Browning X-Bolt Target Max

Watch American Rifleman staff on the range this week to get a close look at an improved X-Bolt rifle from Browning. The Target Max is the latest iteration of the famed X-Bolt action, and it’s designed for long-range work, thanks to its Target Max customizable stock, adjustable trigger, bull barrel and more.

The Armed Citizen® Dec. 1, 2023

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

Review: Mag-Na-Port Custom Ruger Blackhawk Convertible

The author found the just-right performance and managed recoil balance he was looking for with this fully customized single-action wheel gun.

XS Sights Sponsors 6th Annual Meals On Wheels Clay Shoot

XS Sights steps up to the plate as a Presenting Sponsor of the 6th Annual Meals on Wheels of Tarrant County Clay Shoot. Money raised is already making a difference and providing a boost to those less fortunate at this critical time.

I Have This Old Gun: Remington 700 BDL

After Winchester came out with its iconic Model 70, Remington Arms had catching up to do in the sporting-rifle market. Eventually, its answer was the Model 700, a gun that became one of the most recognized bolt-action designs of all time.

New For 2024: EAA Girsan MC9 Disruptor

European American Armory's latest addition to its MC9 handgun line is aptly named, as the Disruptor is intended to provide an incredible range of features at a price point below other similar options.


Get the best of American Rifleman delivered to your inbox.