In comments at Tams, some knucklehead mentions that he habitually dry-fires his firearms.

Dry firing, for the uninitiated, is the practice of pulling the trigger with no round in the chamber.

There are a few firearms that are designed to be dry fired with no apparent damage- Many people claim Glocks can be dry fired with no danger, and the 1911 was regularly dry fired in practice by the US military, as well as was the m9.

it is also possible to sit on the bottom panel of a dutch door and swing back and forth. You can pull an engine from the center of many swingsets. There are plenty of people who use the backside of a crescent wrench as a hammer.

Because you CAN do something, is no specific reason why you should. Firearms are made so that the firing pin can come into contact with the primer of a cartridge, ignite that primer and the associated powder where there is any, and propel the projectile down the barrel. Operating a firearm outside of it’s design parameters is not optimal, and the results will not be optimal. Though you can easily use a Colt SAA as a hammer, it is not how that was intended to be used, and it will potentially damage the firearm.

Likewise, letting the firing pin hit air is not in the design parameters of most firearms any more than using them as a hammer is.

Most, being the operable term. I have heard it claimed that Glocks are designed to be dry-fired, and Supposedly they are. Here’s a picture of one that has been safely dry fired. Revolvers with the firing pins in the hammer have similar issues.

At the Glock booth this Shot Show I heard Glock guys talking with an instructor, who was asking this question- they responded that dry firing was “Ok to clear a gun, or release spring tension on the striker, or for function testing” or whatever, but they certainly didn’t seem to have any aversion to using snap caps, reccomending A-zoom to the person in question. If you do a Google search for “Broken firing pin” images, you come up to about 133,000 images.

Is it always bad to dry fire? Probably not. Are all broken firing pins the result of dry firing? Certainly not. For me, I err on the side of caution, and the very first thing I do with every new firearm I buy is get snap caps. See this? That’s a cased Holland and Holland 12 gauge. See the holes in the middle? Those are made to hold snap caps, nickel plated, with soft spring loaded primers, so the gun can be stored with the tension off the springs. If it’s good enough for Purdey, for Holland and Holland, for LC Smith, for all the major makers, it’s good enough for me. I’ve seen bellied-out breech faces on autos, I’ve seen snapped pins on wheelguns, I’ve seen broken or fractured tips on even Mauser firing pins. I don’t give a damn what anyone else does with THEIR guns, I’m anal retentive about taking care of mine. hell, one of the ways I was taught to strengthen your DA pull was to stick the revolver in a bucket of water and just pull pull pull. Using snap caps, of course. Seemed like good advice then, and it still does now. No better really effective way to work those muscles properly.