In the case of the firing pin I snapped, I was playing with an old Astra 600, God knows how much use it had seen before I met it. Some guns like Glocks for instance are supposed to be immune to this problem. Others like a lot of Eastern Block stuff are very susceptible to firing pin breakage since they usually just float the firing pin in a channel without even using a firing pin spring to control the firing pin movement. Some designs these days even use pre-broken firing pins that bump the rear piece into the front piece to avoid the stresses found in a long thin piece of steel. Bottom line is that I never assume that I can't hurt the gun with substantial dry firing unless the manufacturer explicitly says that it can not be a problem.
Mea culpa though, I do dry fire a lot. I guess some of us take longer to get grooved in on a gun's trigger control than others. Plus I figure the more I dry fire it the more I'm smoothing out the action (assuming that I protect the firing pin from abuse).
My wife on the other hand insists that:
1) OCD is a terrible thing to waste.
2) I wouldn't have to spend so much refresher trigger time on different pistols if I didn't have so many different types to keep up on.
I can't argue 1) but I think it's probably obvious to anyone on this site that too many guns is just an oxymoron.
