"Dry Firing"

Dry firing an unloaded gun without a "snap cap" to take the impact
can deform the areas that stop the firing pin (or striker).
When in doubt, assume that you should not dry fire.
(you should have a colored "snap cap" when shopping for a gun)

If you have no "snap cap", you can take a fired casing and apply
a flexible material over the fired primer, or into the primer well.
(neoprene adhesive or tape works)
.