It's not for me per se. A friend has just picked one up , and I am setting him up w/ snap caps to dry fire the snot out of it. So as per Brad , it will reset well before the snap cap ejects ? Or will one have to be cycled thru for each trigger pull.
If it were me , I'd just dryfire it w/ empty chamber , and periodically inspect firing pin , but for advising someone else I'll take the belt and suspenders aproach.
Sigmas are safe to dry fire. Most S&W guns are. Given that the SDs are nearly identical to the Sigmas I'm guessing they are safe to dry fire also. Although I haven't looked in the manual.