I've been around guns, gun shops, ranges and self appointed experts for a LOOOONG time. I'm 63 now (age is a terrible price to pay for experience) and this thread brought to mind an oft repeated homily, "snapping dogs is bad, snapping turtles is worse but snapping guns is worst of all!". One thing I have found to be universally true, no matter what the shooting discipline, every really good shooter I've met spends a LOT of time dry firing. Look at the mechanics/design of the various firing systems. If there isn't a round in the chamber or a snap-cap in place all of the energy of the hammer/striker spring has to be absorbed by the frame/bushing/firing pin shoulder whichever. Is this bad... it ain't good. Will it immediately destroy you gun? Probably not. When I go boating I wear a life vest, when I shoot I wear ear and eye protection when I dry fire more than a few snaps to verify function I use some type of snap-cap. Just makes sense to me.