The S&W DAOs do not have "double-strike" capability as they are partially cocked or pre-cocked when ready, whereas when the trigger is pulled releasing the hammer (either for real, or dry fire), if the slide does not reciprocate, then the action is not re-set.
See post #17 in this thread http://smith-wessonforum.com/smith-...283628-3rd-gen-s-w-compact-45s-what-look.html
I don't know if it's double strike capable you would have to ask SmithNut, like the above post my 5943TSW is set up that way, but when I sent in my CS9 to change from DA/SA to DAO, they sent it back true DAO in that as long as a magazine is inserted the trigger will go and the hammer will operate normally and there is still a magazine safety if it's not inserted. I believe forum member Fastbolt knows of the CS series as being capable of doing this. You would have to ask him. If I could post a video I would but I'm just not that tech savvy, sorry.
I am asking because I have one of I think 4 that were made up for CPD as sample guns and I was lucky enough to get one. As soon as I figure how to load up pice on my MAC I will show ya.
The picture of the 457D in the other thread is the one I have seen before. The pistol looks to me like it has the slightly extended slide and beavertail to hide the partially pre-cocked hammer, which is the hallmark of the 3rd Gen DAO guns. If that is the system, it does not have second strike capability. I guess it would be nice if SmithNut would enlighten us.
I have a copy on my hard drive of the 457D photo posted by Smithnut. His pistol has the extended slide. The picture of the 457 in this thread does not have the extended slide and also does not have the "D" in the model number so whether it has second strike capability is an open question but can be determined by pulling the trigger a few times with an empty chamber with an empty mag in the frame.
What determines double strike capability is apparently whether or not the hammer is pre-cocked. S&W made two version of the pre-cock, one with an extended slide and one without.