Many thanks to all for your replies!
All of my firearms are of new/modern design and fire centerfire rounds. As far as design, my oldest ‘type’ rifle is probably the PTR91(HK91 Clone). Given the info, all of mine can be safely dry fired, but I my look into getting some of those ‘snap caps’ just to be on the safe side.
Thanks again for your timely replies!
The PTR91 is way cool.
If you get one of those Sterlings that are on the market now, be advised that dry firing them can break the firing pin.