Review of the New DiOrio Firing Pin

[Lawrence Beasley]

What is really the goal for a firing pin to accomplish? We want it to ignite the maximum amount of radial primer compound while delivering as little shock and vibration to the rifle as possible. The new DiOrio firing is superior to all prior firing pin designs at accomplishing this goal. Please click on the photo below to see the footprint of the new pin (if I successfully attached the photo).

The firing pin is .094” in diameter and is flat on the bottom. The firing pin is shaped such that the maximum amount of the .094” diameter is used to make the maximum arc on the radius that fits just inside the solid portion of the case rim. Any strike that lands on the solid portion of the case rim adds nothing to ignition but does add shock and vibration. Also, any part of the firing pin that strikes inside the folded rim (toward the center of the case) adds nothing to ignition but adds to shock and vibration.

How I set up my firing pin I bought from DiOrio a new Firing Pin Slide which holds the firing pin itself on one end and the cocking piece on the other. For a V-3 it is a five minute change. I wanted my firing pin to penetrate .018” because .018” completely closes the gap where the priming mixture is but no more. Any more penetration is needless shock to the system.

I put in a new spring at 17#11oz.
I moved the trigger hangar such that the rear of the hangar was .611” from the tang . You may need a different dimension here but the target is case head penetration of .018”.
Pin fall was .194”
Primer penetration was .018”
After firing, the dimension off the mechanical stop was .019”. Prior to this change the distance off the firing stop had been .011”. This change sounds like a significant but favorable move in reduction of shock and vibration upon ignition. I would like to hear Bill Calfee’s opinion on this supposition if he would like.

My Test results I shot six ARA targets and it was undeniably clear that the new pin yielded better accuracy. But more importantly I did not have even one flier in the six targets. After forty years of shooting I know anything shot in practice is meaningless however there was some wind (4.9 minimum, 13.7 maximum and 10.2 average). My agg was the third best I had ever shot and one target was a 2,450 with 21 of the center dots completely obliterated. Obviously I love the new firing pin. Lawrence Beasley

 

[Bill Calfee]

Friend LB

What is really the goal for a firing pin to accomplish? We want it to ignite the maximum amount of radial primer compound while delivering as little shock and vibration to the rifle as possible. The new DiOrio firing is superior to all prior firing pin designs at accomplishing this goal. Please click on the photo below to see the footprint of the new pin (if I successfully attached the photo).

The firing pin is .094” in diameter and is flat on the bottom. The firing pin is shaped such that the maximum amount of the .094” diameter is used to make the maximum arc on the radius that fits just inside the solid portion of the case rim. Any strike that lands on the solid portion of the case rim adds nothing to ignition but does add shock and vibration. Also, any part of the firing pin that strikes inside the folded rim (toward the center of the case) adds nothing to ignition but adds to shock and vibration.

How I set up my firing pin I bought from DiOrio a new Firing Pin Slide which holds the firing pin itself on one end and the cocking piece on the other. For a V-3 it is a five minute change. I wanted my firing pin to penetrate .018” because .018” completely closes the gap where the priming mixture is but no more. Any more penetration is needless shock to the system.

I put in a new spring at 17#11oz.
I moved the trigger hangar such that the rear of the hangar was .611” from the tang . You may need a different dimension here but the target is case head penetration of .018”.
Pin fall was .194”
Primer penetration was .018”
After firing, the dimension off the mechanical stop was .019”. Prior to this change the distance off the firing stop had been .011”. This change sounds like a significant but favorable move in reduction of shock and vibration upon ignition. I would like to hear Bill Calfee’s opinion on this supposition if he would like.

My Test results I shot six ARA targets and it was undeniably clear that the new pin yielded better accuracy. But more importantly I did not have even one flier in the six targets. After forty years of shooting I know anything shot in practice is meaningless however there was some wind (4.9 minimum, 13.7 maximum and 10.2 average). My agg was the third best I had ever shot and one target was a 2,450 with 21 of the center dots completely obliterated. Obviously I love the new firing pin. Lawrence Beasley

___________________________________



Per your comment in bold orange.




Friend LB:


I opened your picture for you and placed a picture of my DiOrio footprint below it.

__________________________________



Friend LB, the absolute beauty of these new DiOrio pins, it that every shooter can have an exact copy of one...



Look at those two pictures......

Both strike inside the circumference of the rim exactly the same distance from the rim side edge of the footprint.


And LB, mine is in a 10-X action.......which still blows my mind.


Two points:


Your comment I put in bold red, is the same result I'm getting....the lack of exaggerated flippers...


My 10-X pin will still kill it with most of the rounds, using the same ammo, but, there are simply less exaggerated flippers with the new DiOrio pin.



Second point:


Your description of how you developed your ignition, for the new pin, covered all the bases.


It's so nice to have a contraption with enough ignition adjustability so one can do this.


I've got the 10-X action I'm using for my pistol set up just like a DiOrio action....


Your gun fool friend, BC


_______________________



PS:


By the way, when I built my pistol I had no choice but to use the 10-X action.....


It would have been a nightmare for me to make my new V-3 action, which is slightly shorter, fit the factory modified stock....which I love to use.


But if the world don't end, Anthony's going to provide a full XP length V-3, for the masses, and I'm one of the masses.

 

[RAVAGE88]

This is very interesting. I have a very similar feature on the firing pin of my new BR action. Looking forward to comparing the test data....

MB

 

[Bill Calfee]

Friend RAVAGE88

This is very interesting. I have a very similar feature on the firing pin of my new BR action. Looking forward to comparing the test data....

MB

_____________________


Friend RAVAGE88:


Yes, please feel free to post your test data, then I'll be able to compare what I've done with yours.....


Thank you, and good luck with your testing.


Your friend, BC


______________________



PS:


The one major drawback with this type of pin, if it is to be 100% successful, is that it must be absolutely perfectly executed.


The entire width of the rim side edge of the pin, must be exactly the same distance from the edge of the rim...


Likewise, the width of the entire arc of the pin must be uniform, so as not to allow one side to dive into the case head easier than the other.



And finally, the face of the pin must be absolutely parallel to the case head......if not, this design would be no more efficient than the chisel shape.



This is an extremely difficult pin design to execute perfectly........I couldn't do it........

 

[RAVAGE88]

_____________________


Friend RAVAGE88:


Yes, please feel free to post your test data, then I'll be able to compare what I've done with yours.....


Thank you, and good luck with your testing.


Your friend, BC


______________________



PS:


The one major drawback with this type of pin, if it is to be 100% successful, is that it must be absolutely perfectly executed.


The entire width of the rim side edge of the pin, must be exactly the same distance from the edge of the rim...


Likewise, the width of the entire arc of the pin must be uniform, so as not to allow one side to dive into the case head easier than the other.



And finally, the face of the pin must be absolutely parallel to the case head......if not, this design would be no more efficient than the chisel shape.



This is an extremely difficult pin design to execute perfectly........I couldn't do it........

Thank you BC, I'm feeling good about it and pins are in the machine. Based on your input, the only difference in my pin is the .080" diameter vs the .094" diameter of the DiOrio pin. I drew inspiration from photos taken 15 or so years ago....The arc of my pin is inside the rim and I've achieved total uniformity on all planes. Based on method of manufacture, holding tolerance won't be a problem. I'm using a six o'clock SAP ignition, but the design of my SAP is not "usual." I'll send you a PM in a bit, as I believe we're pretty close to one another.

Thanks,
MB

 

[Bill Calfee]

Friend RAVAGE88

Thank you BC, I'm feeling good about it and pins are in the machine. Based on your input, the only difference in my pin is the .080" diameter vs the .094" diameter of the DiOrio pin. I drew inspiration from photos taken 15 or so years ago....The arc of my pin is inside the rim and I've achieved total uniformity on all planes. Based on method of manufacture, holding tolerance won't be a problem. I'm using a six o'clock SAP ignition, but the design of my SAP is not "usual." I'll send you a PM in a bit, as I believe we're pretty close to one another.

Thanks,
MB

________________________



Friend RAVAGE88:



In your original post you stated you have your new pin design in your BR action.


We here at CYA would love to see your new pin.....


You can use the site's software to post a picture of it....



We look forward to seeing it....


Thank you in advance..


Your friend, BC





I'd love to see what an .080" version of the new DiOrio pin looks like, as would the folks here at CYA.

[/QUOTE]


___________________________


PS:


Friend RAVAGE88, if you're designing a new SAP ignition action, you might consider using a .094" diameter pin so you can take full advantage of this style pin design.

The idea is to cover more priming compound, and still be able to drive the pin.......

There would be no sense leaving .014' of priming coverage on the table....

You stated your idea is to improve SAP ignition, not leave .014" of consistency on the table.

 

[RAVAGE88]

________________________



Friend RAVAGE88:



In your original post you stated you have your new pin design in your BR action.


We here at CYA would love to see your new pin.....


You can use the site's software to post a picture of it....



We look forward to seeing it....


Thank you in advance..


Your friend, BC





I'd love to see what an .080" version of the new DiOrio pin looks like, as would the folks here at CYA.

___________________________


PS:


Friend RAVAGE88, if you're designing a new SAP ignition action, you might consider using a .094" diameter pin so your can take full advantage of this style pin design.

The idea is to cover more priming compound, and still be able to drive the pin.......

There'd be no sense leaving .014' of priming coverage on the table....[/QUOTE]

BC,
I just may make a change from .08 to .094, but at the moment, I possess no data that says there's a reason to do so unless smaller dims were tested and good data published somewhere. The .08 version looks no different than the .094, just a slightly smaller arc/footprint. The center of the arc matches the arc of the case rim at the point of ignition (.116 radius), so to grow the arc by .007 per side to increase the footprint is very easy to do in SolidWorks. I sent a PM a little while ago offering more info, etc.

Thanks BC, really enjoying your site,
MB

 

[Bill Calfee]

Friend RAVAGE88

___________________________


PS:


Friend RAVAGE88, if you're designing a new SAP ignition action, you might consider using a .094" diameter pin so your can take full advantage of this style pin design.

The idea is to cover more priming compound, and still be able to drive the pin.......

There'd be no sense leaving .014' of priming coverage on the table....

BC,
I just may make a change from .08 to .094, but at the moment, I possess no data that says there's a reason to do so unless smaller dims were tested and good data published somewhere. The .08 version looks no different than the .094, just a slightly smaller arc/footprint. The center of the arc matches the arc of the case rim at the point of ignition (.116 radius), so to grow the arc by .007 per side to increase the footprint is very easy to do in SolidWorks. I sent a PM a little while ago offering more info, etc.

Thanks BC, really enjoying your site,
MB[/QUOTE]

_________________________



Friend RAVAGE88:


I have no PM here at CYA.....it's never been turned on.........sorry.



About data on the .080" diameter firing pin.....


There has to be tons of data, or the maker of some of the SAP ignition RFBR actions wouldn't have adopted that diameter.


Those SAP ignition RFBR action makers adopt nothing without extensive data.


You might try searching some of the other web sites, as I'm sure you'll find tons of data on the benefit of the .080" diameter pin.


We enjoy having you here at CYA, too.



Your friend, BC


____________________


PS:


We'd love to see your new firing pin......


And read some of your data.


Friend RAVANGE88, I'll be glad to help you post pictures of your new firing pin, and I'll help you with your data posting, too...if you need it..

 

[RAVAGE88]

BC, I appreciate your willingness to help post data; I'll circle back when I'm ready to do so. I wasn't aware your site doesn't support PMs, but prior to knowing that, I sent quite a bit of detail to you via PM. This is a full scale BR action project, three lug, six o'clock ignition, really efficient fire control system with vertical sear, etc., and I'll be back in touch when I'm ready to share more.

Thanks,
MB

 

[Tony K Harper]

BC, I appreciate your willingness to help post data; I'll circle back when I'm ready to do so. I wasn't aware your site doesn't support PMs, but prior to knowing that, I sent quite a bit of detail to you via PM. This is a full scale BR action project, three lug, six o'clock ignition, really efficient fire control system with vertical sear, etc., and I'll be back in touch when I'm ready to share more.

Thanks,
MB

MB,
Please tell me what a fire control system is on a rimfire action. I know there are many fire control systems and I know a bit about the one on the Abrams but in all the bench guns I’ve saw I’ve never seen anything you could call a fire control system. Your action will be a whole nother level from what we have now. Or am I miss understanding you?
TKH

 

[RAVAGE88]

TKH,
As is the case with any firearm, the fire control system is all the components required to set off the round, i.e., trigger, cocking piece, firing pin, firing pin spring. and methods of securing the parts, etc. These components will vary as they apply to specific platforms and therefore, will have different nomenclature applied, as would be the case in a semi-auto platform vs a bolt action. No one component in the fire control system will dictate total success as it relates to the desired outcome, meaning, total success is a product of the whole system.

MB

 

[Tony K Harper]

TKH,
As is the case with any firearm, the fire control system is all the components required to set off the round, i.e., trigger, cocking piece, firing pin, firing pin spring. and methods of securing the parts, etc. These components will vary as they apply to specific platforms and therefore, will have different nomenclature applied, as would be the case in a semi-auto platform vs a bolt action. No one component in the fire control system will dictate total success as it relates to the desired outcome, meaning, total success is a product of the whole system.

MB

I see how you are using the term. I have never thought of a simple bolt action or semi auto action as having a fire control system. Most Fire Control Systems I am familiar with include a sighting component and target acquisition component. But I guess the term can be used for simple systems as well.
I was hoping you had taken our bolt guns and sights to the next level.
TKH

 

[RAVAGE88]

I see how you are using the term. I have never thought of a simple bolt action or semi auto action as having a fire control system. Most Fire Control Systems I am familiar with include a sighting component and target acquisition component. But I guess the term can be used for simple systems as well.
I was hoping you had taken our bolt guns and sights to the next level.
TKH

Well, maybe I have, just in a different context....

MB

 

[Bill Calfee]

Friend RAVAGE88

Thank you BC, I'm feeling good about it and pins are in the machine. Based on your input, the only difference in my pin is the .080" diameter vs the .094" diameter of the DiOrio pin. I drew inspiration from photos taken 15 or so years ago....The arc of my pin is inside the rim and I've achieved total uniformity on all planes. Based on method of manufacture, holding tolerance won't be a problem. I'm using a six o'clock SAP ignition, but the design of my SAP is not "usual." I'll send you a PM in a bit, as I believe we're pretty close to one another.

Thanks,
MB

____________________


Friend RAVAGE88:


It's admirable of you to try to improve SAP rimfire ignition.


But here's what you're up against in doing so:


If by some miracle, or your engineering genus, or a combination of both, you did improve SAP ignition, the absolute best you can possibly hope for is to tie.


Well blueprinted MD-PAS ignition is capable of producing 10-0 case head penetration runs, today.


Therefore, a tie is the best you could possibly obtain.


Your friend, BC


_______________________


PS:


Friend RAVAGE88, you state your SAP ignition is not "usual".


If your firing pin passes "through" the firing pin spring, it's still SAP ignition.

 

[RAVAGE88]

____________________


Friend RAVAGE88:


It's admirable of you to try to improve SAP rimfire ignition.


But here's what you're up against in doing so:


If by some miracle, or your engineering genus, or a combination of both, you did improve SAP ignition, the absolute best you can possibly hope for is to tie.


Well blueprinted MD-PAS ignition is capable of producing 10-0 case head penetration runs, today.


Therefore, a tie is the best you could possibly obtain.


Your friend, BC


_______________________


PS:


Friend RAVAGE88, you state your SAP ignition is not "usual".


If your firing pin passes "through" the firing pin spring, it's still SAP ignition.

Hi BC,
I appreciate your feedback, but I don't think I referred to SAP any differently than "SAP." Spring Around Pin is Spring Around Pin and when I say mine is not "usual," and still call it SAP, it means it's still SAP. Not "usual" merely means I've executed it differently and I've done so by approaching it as a system, not a collection of individual parts only to celebrate a term. It appears, by your continued use of the word, "blueprinted," that PAS ignition won't pass the case head test without a lot of work to somehow make it something other than "usual" as a PAS system. So that would tell me, some equal amount of attention and proper execution as SAP relates to a system, will also attain the same result and the data thus far reveals it to be so.

As far as the case head penetration test, I'm curious to know if you tested the difference, based on Rockwell B, of un-primed cases vs primed cases vs fired cases? Would you expect the same result in a case head penetration test from cases in each condition? Additionally, would you expect to see the same level of hardness across cases in these respective conditions across the more common ammo brands? I.e., would you expect or does your data show that an unprimed Eley case has the same Rb hardness as an unprimed Lapua case? What level of consistency have you seen in hardness from one case to the next in the same lot? Different lots?

Next question: If my SAP system works as well as current well blueprinted PAS systems, would a tie be considered a failure on my part and an obvious waste of my time or an improvement over "usual" SAP systems?

Thanks BC,

MB

 

[Tony K Harper]

Well, maybe I have, just in a different context....

MB

MB,

If you have a working prototype this weekend at Piney Hill Va. they are holding the IR 50/50 Indoor Nationals.

This would be a good place to get many eyes on your product. This will be the best attended match this winter any where east of Chickenfoot, Ga.

TKH

 

[RAVAGE88]

MB,

If you have a working prototype this weekend at Piney Hill Va. they are holding the IR 50/50 Indoor Nationals.

This would be a good place to get many eyes on your product. This will be the best attended match this winter any where east of Chickenfoot, Ga.

TKH

TKH,
I'm in CT and won't be able to make it down, but would love to get something on the calendar soon. I expect to be in VA for a PRS match in early December, maybe we can arrange to meet somewhere.

Thanks,
MB

 

[Bill Calfee]

Friend RAVAGE88

Hi BC,
I appreciate your feedback, but I don't think I referred to SAP any differently than "SAP." Spring Around Pin is Spring Around Pin and when I say mine is not "usual," and still call it SAP, it means it's still SAP. Not "usual" merely means I've executed it differently and I've done so by approaching it as a system, not a collection of individual parts only to celebrate a term. It appears, by your continued use of the word, "blueprinted," that PAS ignition won't pass the case head test without a lot of work to somehow make it something other than "usual" as a PAS system. So that would tell me, some equal amount of attention and proper execution as SAP relates to a system, will also attain the same result and the data thus far reveals it to be so.

As far as the case head penetration test, I'm curious to know if you tested the difference, based on Rockwell B, of un-primed cases vs primed cases vs fired cases? Would you expect the same result in a case head penetration test from cases in each condition? Additionally, would you expect see see the same level of hardness across cases in these respective conditions across the more common ammo brands? I.e., would you expect or does your data show than an unprimed Eley case has the same Rb hardness as an unprimed Lapua case?

Next question: If my SAP system works as well as current well blueprinted PAS systems, would a tie be considered a failure on my part and an obvious waste of my time or an improvement over "usual" SAP systems?

Thanks BC,

MB

_______________________



Friend RAVAGE88:


You're most certainly welcome.



Friend RAVAGE88, only you can be the judge of the value of your time.



In my case, my time is so valuable that there's no way I'd waste it attempting to build a new SAP ignitioned RF action, no matter what version of SAP ignition.


I can't imagine spending time trying to "tie" an existing product.......any product.



But again friend RAVAGE88, you're the judge of the value of your time, not me.


Your friend, BC

 

[RAVAGE88]

_______________________



Friend RAVAGE88:


You're most certainly welcome.



Friend RAVAGE88, only you can be the judge of the value of your time.



In my case, my time is so valuable that there's no way I'd waste it attempting to build a new SAP ignitioned RF action, no matter what version of SAP ignition.


I can't imagine spending time trying to "tie" an existing product.......any product.



But again friend RAVAGE88, you're the judge of the value of your time, not me.


Your friend, BC

Thanks BC, but please don't misunderstand, I never said my goal was to tie anything, I merely asked a reasonable question based on your comments about what I was up against and the best I could hope for. In your own way, you did answer my direct question though, and I appreciate that.

Any insights about your data on Rb specs of cases in the varied conditions? Across multiple brands? How consistently do you see a 10-0 case head result when testing "blueprinted" PAS systems? What were the results when you tested SAP systems? Were the SAP systems, as tested, what you'd consider "blueprinted?" My point to all these questions is, as you likely know, there are A LOT of variables when it comes to any test and to completely understand and convey the data is to understand and accommodate the variables, otherwise, the data is skewed one way or the other, generally, in the favored direction.

Thanks again BC, looking forward to your answers.

MB

 

[Bill Calfee]

Friend RAVAGE88

Thanks BC, but please don't misunderstand, I never said my goal was to tie anything, I merely asked a reasonable question based on your comments about what I was up against and the best I could hope for. In your own way, you did answer my direct question though, and I appreciate that.

Any insights about your data on Rb specs of cases in the varied conditions? Across multiple brands? How consistently do you see a 10-0 case head result when testing "blueprinted" PAS systems? What were the results when you tested SAP systems? Were the SAP systems, as tested, what you'd consider "blueprinted?" My point to all these questions is, as you likely know, there are A LOT of variables when it comes to any test and to completely understand and convey the data is to understand and accommodate the variables, otherwise, the data is skewed one way or the other, generally, in the favored direction.

Thanks again BC, looking forward to your answers.

MB

_________________________


Friend RAVAGE88:


You're most certainly welcome.


Your friend, BC