http://en.wikipedia.org/wiki/SIG_P226#DAK_VersionSIG recently released an improved version of the double-action only (DAO) pistols; this version is called the DAK (for Double Action Kellerman, after the designer of the system). The DAK capability is available in 226, 229 and 239 models. When firing the pistol the first trigger pull is only 6.5 lbf (compared to 10 pounds for the standard DAO). After the pistol fires and the trigger is released forward the trigger has an intermediate reset point that is approximately halfway to the trigger at rest position. The trigger pull from this intermediate reset point is 8.5 lbf. If the trigger is released all the way forward, this will engage the primary trigger reset and have a trigger pull of 6.5 lbf. To engage the intermediate reset, the trigger must be held to the rear while the slide is cycled, either manually or by the recoil of a round being fired. The United States Coast Guard has adopted this firearm as its PDW (Personal Defense Weapon), replacing the older M9 pistol.
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