For those who (like me) didn't know this already: I finally did a little research to see if I was damaging my firing pin and/or breech face when I failed to count my shots with my 10/22 and dry fired after the last round cleared. I'm not! I'd always understood that you couldn't dry fire a rimfire weapon or an older revolver as you'd damage it, but I've just learned I was wrong as far as Ruger 10/22's and Mark 1,2,3 & 4 pistols. I found out that both the 10/22 and the Mark 1- 4 pistols can be safely dry fired due to their having a stop pin that keeps the firing pin from hitting the breech, and the stop pin being hollow means it also slightly flexes, acting as a spring to limit wear and stress, so snap caps aren't required. Warning: I didn't research other Ruger rimfire weapons, so I don't know if this holds true with other models.