Clarifying Double Action Only (DAO)

by
posted on April 23, 2015
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
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.

Latest

Henry Guns For Great Causes F
Henry Guns For Great Causes F

Firearm Industry Philanthropic Efforts Endure, Despite Lagging Gun Sales

Gun sales in 2025 may not eclipse records, but the firearm industry’s generosity continues to abound, even within challenging economic circumstances.

Product : Ten21 Tactical “The Junk Drawer” Tripod Hammock

Precision shooters using tripods to support their rifles can keep miscellaneous gear organized and within reach by attaching The Junk Drawer by Ten21 Tactical to the tripod’s legs.

Review: SAR USA SAR9 SOCOM Compact

The SAR9 SOCOM Compact from SAR USA packs popular tactical features into a compact package.

A Jakl In Bullpup Clothing: Palmetto State Armory's Olcan

Palmetto State Armory adapted its piston-driven Jakl rifle design into a bullpup configuration it calls the Olcan.

150,000 NFA Applications Filed On Day 1 After $0 Tax Stamp Becomes Official

Approximately 150,000 NFA enthusiasts filed their paperwork through ATF’s electronic system in just the first 24 hours of 2026, the first day after the $0 tax stamp for most NFA items became official.

Gun Of The Week: Caracal USA CMP9K

Caracal's CMP9K pistol is based on a design originally produced to replace the aging stock of Heckler & Koch MP5s in United Arab Emirates service.

Interests



Get the best of American Rifleman delivered to your inbox.