Single Action OnlyAbbreviated SAO
Your two most common types of SAO guns are 1911 pattern semi-automatics and your "Western" revolvers" such as the Colt Single Action Army. A lot of people get confused on this as they mistake action type and trigger type. With both the 1911 and single action revolver, the hammer must be cocked in order for the gun to fire. Pulling the trigger causes one action, that of the hammer to fall and make contact with the firing pin. To confuse you even further, there are some single action only guns that are striker fired as they are fully cocked by the manual cycling of the slide or other operation. Two examples of single action, striker fired guns are the HKP7 family and the Springfield XD (includes XDM) line. There are some that will disagree and say that striker fired guns are not SAO. But looking at the requirement that pulling the trigger facilitates only one action, the release of "X" that initiates the firing sequence, YES they are single action...
I'm also guessing that you don't have a SFS kit installed. Correct?
*Para Ordnance (Light Double Action) LDA models really can't be considered 1911s.