Why only one firing pin?

A place to discuss non-discipline specific items, such as mental training, ammo needs, and issues regarding ISSF, USAS, and NRA

If you wish to make a donation to this forum's operation , it would be greatly appreciated.
https://www.paypal.com/paypalme/targettalk?yours=true

Moderators: pilkguns, m1963, David Levene, Spencer, Richard H

Post Reply
User avatar
_Axel_
Posts: 90
Joined: Mon Mar 05, 2007 3:29 am
Location: Sweden

Why only one firing pin?

Post by _Axel_ »

Some older (often cheap) open bolt .22 rifles (banned in some places) have one fixed firing pin that strikes the rim in two places (integral with the bolt face usually). This is often given as one reason why they are so reliable. But why then not let all rimfire guns have more than one firing pin, should not be hard to design!? Some very expensive guns, like my old Morini CM 22 had a rather fragile looking firing pin (it never broke though)!

Are there any normal bolt or semi auto guns like this?
Rover
Posts: 6986
Joined: Sat Nov 15, 2008 4:20 pm
Location: Idaho panhandle

Re: Why only one firing pin?

Post by Rover »

Great question!

I have found that many dud .22 rounds will fire with a strike in another spot. That should up the odds against an alibi.

Perhaps it would be because it would take a harder strike (heftier spring) for two firing pins.
Martin Catley
Posts: 170
Joined: Wed Dec 22, 2004 4:19 am
Location: New Zealand
Contact:

Re: Why only one firing pin?

Post by Martin Catley »

I have read of dual pins used in Bench rest rifles in the USA but they did not seem to catch on.
User avatar
renzo
Posts: 427
Joined: Thu Aug 05, 2010 4:16 pm
Location: Santa Fe, Argentina
Contact:

Re: Why only one firing pin?

Post by renzo »

Yours is not a revolutionary idea, believe me, but equally a very good one!!!

Rewind back to 1869, the Military Swiss Vetterli Rifle, Musket & Carbine in caliber 10.4 x 38 R (rimfire) or .41 Swiss as Remington labeled their ammo, has a single firing rod that forks in the striking end, hammering the rim in two places at once, 180 degrees apart, and that was made exactly for the same reason you thought, reassuring that the primer made "boom" instead of "Click" when fired in anger.........
User avatar
nglitz
Posts: 182
Joined: Sun Mar 07, 2004 10:48 am
Location: Hamilton Square NJ

Re: Why only one firing pin?

Post by nglitz »

Good rimfire ammo has very uniform primer around the rim. Cheaper, less so. That's where a double firing pin might help.

It's also likely why Remington advertises Ely priming in their target ammo.
Norm
in beautiful, gun friendly New Jersey
machinist mike
Posts: 79
Joined: Sat Oct 13, 2012 6:36 pm

Re: Why only one firing pin?

Post by machinist mike »

The original government training rifle, model 1922, had a duel firing pin. 2020 of this model were made in the years 1922 - 1923. Later models, 1922 m-1, and 1922 m-2, deleted this feature in favor of a single pin.
PFribley
Posts: 346
Joined: Thu Aug 19, 2010 8:42 pm

Re: Why only one firing pin?

Post by PFribley »

Maybe the reliability and better quality of 22lr ammo over the years made those pins redundant.
Rover
Posts: 6986
Joined: Sat Nov 15, 2008 4:20 pm
Location: Idaho panhandle

Re: Why only one firing pin?

Post by Rover »

Naahh.
User avatar
SPPcoach
Posts: 238
Joined: Sun Jul 13, 2014 10:18 pm
Location: Arizona
Contact:

Re: Why only one firing pin?

Post by SPPcoach »

My .02 cents. The dual firing pin would make the rifle/pistol more expensive. If the user is willing to spend more on a product to gain reliability, then they are likely to spend that money on higher quality ammunition that has a more reliable priming system. That way they are less likely to have a dud in their box. The users of cheap ammunition are also the purchasers of cheaper firearms. So that compounds the likelihood of it happening to them. Not all rimfire ammunition is primed the same way. The more reliable and expensive method is to use centrifugal force to spin the priming compound to the edge of the case. The cheaper and less reliable is to squirt it into the case with a nozzle.
During our team practice, my youth athletes will shoot ~150 - 300 rounds each. That could be 3000 - 4000 rounds in a practice. Approximately 10 of those rounds will not fire and I would guess that 5 of those will fire the second time. The reason I have them reload that round is that is that it makes a great 'ball and dummy' drill. They don't know if the gun will go off. That is a good learning opportunity.
I definitely have experience on what rimfire ammunition is more/less reliable in average handguns (Ruger MK, Buckmarks, S&W, CZ).
mbradley
Posts: 110
Joined: Thu May 12, 2011 8:50 pm

Re: Why only one firing pin?

Post by mbradley »

The purpose of a dual or tri firing pin system was not to insure the firing of a potential dud round: It was to insure a relatively more consistent burning of the powder. A smallbore rimfire cartridge has an enormous amount of space relative to the amount of powder. That powder can lay in any sort of configuration relative to the primer. By having multiple impacts of the firing pins, the thought was that you would have a more consistent firing of the primer relative to the arbitrary nature of where the powder was. The the 6 o'clock firing pin was also an attempt to address this issue.
Tim S
Posts: 2018
Joined: Mon Jan 03, 2011 11:33 am
Location: Taunton, Somerset

Re: Why only one firing pin?

Post by Tim S »

At what period where dual firing pins common? Until the 1940s some .22 cartridges were loaded with a mix of black and nitro powder. The .22LR case is oversized for a nitro charge, but not for black powder.
Rover
Posts: 6986
Joined: Sat Nov 15, 2008 4:20 pm
Location: Idaho panhandle

Re: Why only one firing pin?

Post by Rover »

I have to laugh. In a Free Pistol practice session with John Zurek, he dragged out a brick of really crap ammo. (I would tell you the brand if I remembered.)

It made for a great "ball and dummy drill." We also tried a second strike with it.
acanais57
Posts: 1
Joined: Mon May 29, 2017 8:32 am

Re: Why only one firing pin?

Post by acanais57 »

renzo wrote:Yours is not a revolutionary idea, believe me, but equally a very good one!!!

Rewind back to 1869, the Military Swiss Vetterli Rifle, Musket & Carbine in caliber 10.4 x 38 R (rimfire) or .41 Swiss as Remington labeled their ammo, has a single firing rod that forks in the striking end, hammering the rim in two places at once Mutuelles senior, 180 degrees apart, and that was made exactly for the same reason you thought, reassuring that the primer made "boom" instead of "Click" when fired in anger.........
Thanks a lot for the information. This will allow us to properly maintain our weapon.
mikeyj
Posts: 97
Joined: Fri Sep 18, 2015 3:34 pm

Re: Why only one firing pin?

Post by mikeyj »

I used to own a Mexican made Cabanas rifle that used crimped 6mm rimfre blanks to propel a .177 round ball down a rifled barrel. The "firing pin" was sort of floating bolt that had two protrusions machined in the end. It rested against the cartridge, and when the trigger was pulled, a heavy bolt slammed forward, hitting the floating bolt and driving it into the blank. No doubt part of the reason was poor quality Mexican blanks, but I think it also lessened stress on the pins.

There were as few .22s made in the pre war years that fired from an open bolt, and I believe some of them also had a dual firing pin machined into the bolt. (Most were European, but one was American- the Marlin 50.)
User avatar
renzo
Posts: 427
Joined: Thu Aug 05, 2010 4:16 pm
Location: Santa Fe, Argentina
Contact:

Re: Why only one firing pin?

Post by renzo »

mikeyj wrote:
There were as few .22s made in the pre war years that fired from an open bolt, and I believe some of them also had a dual firing pin machined into the bolt. (Most were European, but one was American- the Marlin 50.)
When I was young(er) they made in my country a semiauto .22 carbine that fired from an open bolt, and it had no "firing pin" as we know it: it simply had a protrusion that crossed the bolt face from side to side (through its diameter) that was shaped as a triangle, and stroke the head directly across, hitting the rim in both the opposite sides, I had one and - obviously - never had a misfire, although it was hell to keep it aligned during the bolt travel if you were out for precision................

I remember one of our then-common military governments forbade it because it was extremely easy to turn it a machine gun and back, as a simple metal piece could be put between the sear and the block, obviating the disconnector.
mikeyj
Posts: 97
Joined: Fri Sep 18, 2015 3:34 pm

Re: Why only one firing pin?

Post by mikeyj »

[quote="renzo"


When I was young(er) they made in my country a semiauto .22 carbine that fired from an open bolt, and it had no "firing pin" as we know it: it simply had a protrusion that crossed the bolt face from side to side (through its diameter) that was shaped as a triangle, and stroke the head directly across, hitting the rim in both the opposite sides, I had one and - obviously - never had a misfire, although it was hell to keep it aligned during the bolt travel if you were out for precision................

I remember one of our then-common military governments forbade it because it was extremely easy to turn it a machine gun and back, as a simple metal piece could be put between the sear and the block, obviating the disconnector.[/quote]

I believe the Cabanas had a similar "firing pin" rather than two, as I previously stated. Open bolt .22s were banned here for similar reasons.
Post Reply