Gunsmithing Dry firing and broken firing pins

[Sheldon N]

I've heard some folks say dry firing a bolt action rifle is bad for the firing pin. I've also heard others say to go right ahead it won't hurt anything.

I've broken two firing pins in the last few months while dry firing the rifles for practice. Two different custom action makes involved, one at around 10k dry fire cycles and the other at 5k cycles.

What do you all think about dry firing? Should I expect more failures if I continue to dry fire or has my recent experience been an anomaly?

 

[SuperSneakySniper]

Im also curious about this, as Im pretty sure i have the same two custom action makes, and I dry fire ALOT. Im wondering if it is at all possible those whove had firing pins break just had pins from bad batches?
I also wanna know if this is an action/bolt design issue or just a lroblem with the integrity and strength of the pins?

 

[DesertMonkey]

I have 10's of thousands of dry fires on my AW and have never had a problem I know of another AW that has close to a million dry fires never had a problem either.

 

[Sheldon N]

When I called both manufacturers they were very surprised as though it was not a common occurrence. I have heard of one other person with one of the same actions having the same issue. I'm going to keep dry firing with one so we'll see if it breaks again.

 

[Deadshot2]

I'm like most others and have dry fired many, many, times. It's good practice and doesn't cost anything.

I have read notes from some suppliers of light-weight firing pins, usually part of a "quick lock time kit", saying dry firing is to be avoided. Makes sense to me as some lighter weight metals are often more brittle and the process to lighten firing pins often also involves removing metal.

As for conventional pins? I always keep a spare so I don't sweat it. FWIW, my "spares" (one for each rifle) are still in their original packages.

 

[sheepdog697]

Dry firing is an excellent way to make sure your fundamentals are there without recoil added. As many others have mentioned i have done this in all my guns since i started shooting and i have never had and issue with anything.

 

[missed]

My Mausingfield has thousands of dry firing cycles on it. My opinion is it should be able to handle the dry firing cycles.

 

[dinc3]

Any modern arm should be able to be dry fired. If it breaks, something was wrong. Better to find out at home than on the top of a mountain.

 

[Sheldon N]

Yep, or broke at home. Just didn't find out until I was either at the range, or the second time at a match on the clock.

 

[Ledzep]

I'm curious, where do they break?

I'd think just in front of the flange about 3/4 the way forward, but I could be wrong. Another question is what kind of temperatures?

Ideally they should be able to handle an indefinite number of cycles, but impacts are one of the harder things to design for. Steels can be especially weird under the ductile-to-brittle temp. Takes a surprisingly small amount of energy to break, and the higher the carbon content, the higher that temp is (the hotter it needs to be to bend instead of break).

That said, I think you're unlucky. Either unlucky to break 2 pins that were constructed well, or unlucky to get parts with incorrect heat treat (insufficient temper maybe???) or some other defect.

 

[Sheldon N]

Both times the break was right at the junction of the tip of the firing pin where it meets the body of the pin. All the dry firing was done indoors at normal room temperatures.

 

[LRI]

It depends on the action and type. Certain 22's for instance will kill a barrel almost instantly if you dry fire. The striker will peen the edge of the breech. It can be ironed out to save the gun, but it's something to be avoided.

There are two principle issues. If the cocking cam is purchasing the bottom of the cam on the bolt, it can lead to a failure in the back end of the striker. This is rare. The more likely failure is up front where the narrow portion of the pin transitions and increases in OD. Most centerfire guns will tolerate this all day long. Some will not. It has to do with duty cycle and the loads applied per square inch.

Ted from ARC has devoted a considerable effort to this. New Mausingfields in fact have a revised striker design because of it.