Hello all. Recieved my carry permit about a year ago and finally purchasing an SW99OL in .40 s&w. I'm somewhat new to the world of handguns. Always been around rifles and shotguns but handguns for self defense is an entirely different thing than hunting and target shooting. Being unfamiliar with the terminology for handguns and still getting used to my 99OL I thought this site would answer a lot of questions I have about this handgun, especially concerning the action. Still a bit sketchy about what double action, double action only, quick action, single action and all configurations that seem to be out there.