I know it says to not dryfire the pistol, what does it exactly damage? Could that be stopped by using a fired case in the chamber to give the firing pin something to strike?

Why are you asking for an explanation/justification of a manufacturer's recommendation? Don't you think they know what they are talking about?

The recommendation for as long as rim-fire guns have existed (157 years) is do not dry fire them! The reason is there are several areas in a rim-fire that can be damaged by doing so.

If you feel you must then buy some "snap caps" and use them religiously. It is necessary to have something to cushion the firing pin, and fired cases will only do this for one snap, two at best.

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Gunsmithing since 1961

While there are a few rimfires that are designed to be dryfired without damage, dryfiring most will cause -- immediately or eventually -- breakage of the firing pin or peening of the firing pin tip, and damage to the chamber mouth. S&W warns not to do it in the M&P .22 manual, but if you have a rimfire and don't know FOR SURE that dryfiring is safe -- DON'T DO IT without a snap-cap.

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Pisgah

There are several threads around here about using the yellow (number 3?) plastic wall anchors as snap caps for 22 rimfires....

Which ones?

Yes, you can use a fired case (make sure it's already fired!). Other respondents to your question have explained how dry firing a .22 rimfire can cause damage so I'll not go into that.

Geez, he's just seeking an explanation as to why. Not everyone is omniscient like you.

I was asking to gain the knowledge as I thought this was the forum to do so. If I didn't think they knew what they were talking about I would have just had my son dryfire it without seeking more information. You point out there are several areas that can be damaged (which was part of my original question) can you go into more detail? I ordered snap caps already so hopefully that will help.

Here is what happens to a K-22 cylinder when you dry fire.

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Mike
S&WCA #3065

Good advice in your post but bad opening comment. You cannot teach by criticizing. You cannot learn by being criticized. Education is taking a person by the hand and explaing some thing to them. Never diminish your good advice by criticizing a questioner.

Most .22s and a few centerfire semi-autos shouldn't be dry-fired. In the case of some centerfire guns, dry-firing may damage the firing pin or as was the case with the first years of CZ-75Bs, the firing pin retention roll pin.

Ruger .22s have a firing pin stop that keeps the firing pin from damaging the chamber lip. (The firing pin stop can be damaged, over time.)

Beretta Tomcats (.32 acp), when they were first introduced, came with a warning not to dry fire. (I don't know what the manual says, now.) I dry-fired mine a lot (it had a ****** tritter), using snap caps, but still broke a firing pin; the firing pin struck so strongly, it quickly ate up the snap cap before I noticed the problem. (The guns are so small that most gunsmiths don't want to try to do a trigger job -- hard to do it!)

Dry firing most 22s will peen the chamber causing feeding issues. Dry firing will also eventually cause breakage of the firing pin. Your best bet is to just not do it. If you are determined to do so for some reason, then a fired case will cushion the blow enough to minimize any damage. The case should be rotated slightly for each shot, though. You may be able to use each case for 3 or 4 shots, so it's really not convenient.

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Or something like that . . .

Before putting any rimfire firearm away - first check and be double-damn sure the gun is UNLOADED.

On most semiauto .22s, both pistol and rifle, I learned early on to retract the bolt very slightly before pulling the trigger to release the hammer over an empty chamber. The hammer will strike the rear of the bolt, and often the firing pin, but the firing pin will not impact the chamber area. This is the correct way to lower the hammer to help prevent spring set.

With bolt actions, to release the firing pin over an empty chamber, move the bolt forward, and with the bolt handle UP, pull the trigger and lower the handle at the same time. The firing pin spring will relax gently in the process.

With revolvers, always lower the hammer gently, holding it with the thumb.

These procedures will allow relaxation of the springs without damage to the chamber area.

John

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- Cogito, ergo armatus sum -

I have an Anchutz Achiever, a kid-size bolt action designed to let small stature folks get a start on shooting. It came with (or I bought, can't remember) a special firing pin that was shortened and flattened so that it would not damage the breech face when the gun was dry fired.

Swapping firing pins takes but a minute or so (plus whatever time it takes to find and retrieve the spring loaded detent-ball that usually decides to disappear when you take the two halves of the bolt apart to do the swap.) I suspect other Anchutz rifles have the same option, but I've not heard of it with other brands.