Tips for dryfire on MKIII?

[melchloboo]

I am practicing on my MKIII by dryfiring on empty brass. Although I can get into a rhythm, its sort of tedious to eject the brass, pop it back in, release the mag, close the slide, insert mag, fire, do it all over...

Am I missing an obvious way to make this easier?
Thanks

[recumbent]

read this

http://www.guntalk-online.com/forum/vie ... highlight=

[Bullseye]

If you have a solid firing pin stop then removing the firing pin for extended dry firing practice is a viable option. If you have the roll pin style firing pin stop then the plastic inserts are a good idea.

R,
Bullseye

[DancesWithSquirrels]

They make .22 dummy rounds. They usually come in packages of 10. Buy a package or three and load them into your magazines. Then when you are dry firing you can pull the trigger that many times before you have to reload.

DWS

[melchloboo]

By dummy rounds do you mean they are plastic, or brass? Any reason why used brass any better or worse then some of the plastic suggestions (like wall anchors)?

I have the newer "roll" pin stop.

I wonder how hard it would be to acquire a used/damaged bolt for this purpose, just to remove the firing pin and put the bolt in for practice with no brass?

[DancesWithSquirrels]

The ones I have are actually made of aluminum but I have seen plastic ones as well. I load up ten of them in a magazine and I can dry fire ten times by just yanking the slide back between trigger pulls.

DWS

[Adam67]

My understanding is that the Mark III (And I'll assume the II as well) can be dry fired at will. My manual said you can do it and I've heard from others who contacted Ruger directly and the people at Ruger said it wouldn't hurt it.....no snap caps needed.

[Bullseye]

Dry firing without damage only applies to a certain degree. If one excessively dry fires the pistol without a insulation cartridge then damage can occur to the firing pin stop pin. Here's an example of a stop pin damaged by excessive dry firing.



This type of damage to the stop pin will result in the chamber mouth being peened by the face of the firing pin too. This stop pin stretched through stress to allow the firing pin to reach the chamber mouth and deform it.

Periodic inspection of the firing pin stop pin can prevent chamber damage. Early inspections for wear will reveal if the stop is beginning to stress before any damage to the breech face.

Hope this helps.

R,
Bullseye

[melchloboo]

Not to belabor the issue, but what stops the firing pin stop from deforming through repeated live fire use? In other words, are the tolerances so fine that the thin barrier provided by a brass or plastic shell stops the firing pin from striking the pin stop altogether? Or does it just soften the blow? Further, if one manufacturer puts out brass rims that are thinner and/or softer than others, is that a potential problem?

Lastly, I don't understand why a strike against the face is necessarily fatal to the pistol. Can't the firing pin be replaced/repaired? Would the ding on the breech face destroy the barrel's ability seal around the expanding cartridge? Clearly none of this is good, but does the risk/benefit of dryfire practice overwhelmingly favor practice?

[Bullseye]

All good questions, let me take them on one at a time.

The firing pin is constructed of hardened steel. Anything that it comes in contact with is going to be deformed, as long as that material isn't harder than the pin. When a pin strikes the chamber face, it isn't a fatal event, but it will cause feeding and detonation issues. Here's the type of damage one can expect from a firing pin striking the chamber mouth.



There is a tool called a rimfire chamber iron that can smooth out the dent. The tool inserts into the chamber and presses the dented metal back out of the chamber's diameter. They run around $20 retail at most gun parts suppliers.

There is enough mass in the firing pin and hammer combo to force the pin forward and crush whatever the pin's point contacts. However, the pin does not have enough mass, or travel, to overcome any material directly against the chamber face. The softer material absorbs the the energy and does not transfer the inertia to the chamber lip. The brass from a rimfire cartridge crushes, but it doesn't crush to the point of allowing the firing pin to smash with great force against its stopping device. The brass prevents the firing pin from traveling fully forward and striking the stop pin with full force. The plastic dummy devices perform the same function.

The stop pin is also hardened steel but the RC factor of the stop is less than the firing pin itself. Otherwise when the pin hits the stop, the firing pin would be deformed, not the stop pin. A deformed firing pin wouldn't travel smoothly in the bolt's firing pin track and light strike misfires would begin happening to the pistol.

The firing pin when fully extended against the stop is just a few thousandths from touching the breech face. The inertia of an unimpeded pin smashing against the stop pin eventually will cause the metal to fatigue and stretch. The same can happen with an improperly heat treated firing pin. This happened in the 1990's, where many firing pins were improperly heat treated, they overstressed and cracked off near the end.

Finally, no one is saying that you cannot dry fire the pistol. That is something that must be accomplished to perform maintenance on the pistol. All I'm saying is excessive dry firing practice can damage the pistol if the practice goes on unchecked. Periodic inspection can reveal minor stressing before it becomes a significant repair issue.

R,
Bullseye

[melchloboo]

Thanks! Very informative. Just one more question...maybe I am not 100% understanding the definition of dryfiring... When you use the term do you mean a completely empty chamber, or also when one uses empty brass or plastic in the chamber?

Because I don't see the difference between dryfiring with empty brass (as long as repeated strikes in the same spot on the rim are minimized, i.e. rotate the shell between strikes) and a live round in terms of effect on the firing pin. I thought as long as I have empty brass in there, or plastic, no worries?

[Matt_S]

I believe that the term dry firing references an empty chamber. I plan to start putting the plastic achors in my MKIII from now on. Great thread!!

[Bullseye]

If you have something in the chamber to minimize the firing pin from striking the stop under full force then you have no worries. Plastic or brass will insulate the chamber rim and the firing pin stop from repeated full force hits. The description I gave does not include routine dropping of the hammer to uncock it. This stress condition will only happen if someone spends extended sessions of dry firing practice.

R,
Bullseye

[iScream]

Does anyone know if the rolled pin is more or less likely to deform than the older one? I really want to do some dry fire practice with mine once I get the trigger fixed up. Can I pre-order a new stop pin and change it after every 500 dry fires or something like that?

Thanks,
Chris

[Bullseye]

The new roll pins are too new. I haven't seen any empirical data to support or prohibit the practice of dry firing with the new style roll pins. Caution is the way to go when dry firing with the Rugers, don't over do it. If the stop pin deforms the breech face will get dented. This can be fixed but it takes a chamber iron and that's not something everyone has laying around for their rimfires. The best thing to do is use a buffer in the chamber to protect the breech face. The plastic wall anchors are probably the best and most inexpensive tool for this purpose.

R,
Bullseye