Cocked or dry fire?

[BHJ]

The firing spring tension on bolt guns can be relieved by holding the trigger as you close the bolt. This prevents the sear from engageing. No need to dry fire because the rifle isnt cocked. My bolt guns are always stored in this fashion.
BHJ

 

[07JKX]

A centerfire firing pin hits air when dry fired. A rimfire, especially an older one can be driving the firing pin into the steel chamber rim the round normally rest on for firing. Many firing pins have been broken on old 22's from dry firing. Many modern rimfires now have been improved, and are completely unharmed by dry firing. Ruger even recommends dry firing as a means of getting aquainted with their firearms and states there is no harm to their rimfires at all.

what he said... you can look inside the chamber of a rimfire weapon and see if the is a slot cut out on the chamber/barrel rim where the firing pin would strike. If it is there, the the firing pin will not hit anything under dry fire.

The only centerfire pistol I had was an old CZ-52.... and although centerfire, the firing pin would break after repeated dryfire. I tested and broke one firing pin after 45ish dry fires and the second one lasted just over 60. I had read up previously on that issue and bought 25 firing pins for 15 bucks. lol