Can using a centerfire firing pin on a rimfire model affect ignition?

[WVGunman]

This question is about the old Marlin Levermatic. Marlin made both center- and rimfire models of the gun. I have one of the rimfire models that fails to set off a round about once every 15 shots. I have been very puzzled by this, because the firing pin mark is there on every round, and looks to be about as deep as on the ones that do go off. Invariably these rounds fire when I put them back in the chamber and try again elsewhere on the rim. This happens with other rimfire guns and cheap ammo sometimes, but happens far too often with this gun to be the ammo.
What jumped out at me is that the impression of the firing pin on the case is round. I have never seen a rimfire firing pin that was not square or rectangular in cross section, with a flat tip. I noticed this round tip, but didn't really know if it meant anything.
I had read elsewhere that sometimes the firing pins on these guns peen somehow, and this can affect ignition, so I started looking around for second-hand firing pins. And I noticed something interesting.: the pins for the rimfire models ARE square in cross-section and flat-tipped, whereas the pins for the centerfire guns are rounded!
Rimfire pin. Note the tip:
Centerfire pin, almost identical, but again note the tip [Archer]Just the tip![/Archer]:


I'm now wondering if someone replaced the firing pin on this gun with a centerfire pin, either not knowing or not caring about the difference. The pin still lands on the rim, but that rounded tip can't possibly be crushing as much of the rim as the flat tipped pin.
Is it possible that this alone could be causing my poor ignition problem?

 

[danez71]

Is it possible that this alone could be causing my poor ignition problem?

I believe, Yes, it could.

 

[Deleon517]

Unless the firearm was purchased by you brand new I would replace it just off the fact it doesn't look like it should. 1 in 15 failures to fire isn't something I would trust my life with.

My EDC pretty much eats everything I throw at it except some really cheap stuff I grabbed once when I just sort of ended up at the range unplanned. It fired but 1-2 rounds per mag(13) would fail to extract. Fired 100 rounds of that cheap stuff and each mag had a problem. Went home cleaned and lubed and went back the next day. Have gone through 1000+ since than with ammo i know works and no issues

 

[Slamfire]

What jumped out at me is that the impression of the firing pin on the case is round. I have never seen a rimfire firing pin that was not square or rectangular in cross section, with a flat tip. I noticed this round tip, but didn't really know if it meant anything.
I had read elsewhere that sometimes the firing pins on these guns peen somehow, and this can affect ignition, so I started looking around for second-hand firing pins. And I noticed something interesting.: the pins for the rimfire models ARE square in cross-section and flat-tipped, whereas the pins for the centerfire guns are rounded!

I have a couple of Win M52D's that manage to have reliable ignition with their round firing pins. Think my Stevens M416's and my Rem M37 have round firing pins too. Round cross sections are not the issue.

You have not posted pictures of the cartridge rims, which would be helpful if the firing pin strike is way off the rim, or extremely shallow indentations were shown.

I believe that the most likely cause of your ignition problems is inadequate firing pin protrusion. I have had this issue when the firing pin on my stainless Ruger MkII peened and I had misfires and weak ignition:






Whatever stainless steels Ruger used, they were soft, and the fact of the matter is, I don't need rust resistance in this application. I need toughness and retained hardness. An alloy tool steel Volquartsen firing pin did the trick:



I have seen a surprising number of ignition problems in rim fires, and there are several sources. Firstly, as above, insufficient firing pin protrusion. Then, weak mainsprings. Weak firing pin strikes are not always obvious.

I purchased a M586 S&W that had been fired around 60,000 times in PPC competition by the previous owner. He had always used Federal primers. No problemo. I however, used WSP, ball powder, and shot the thing in cold weather. This lead bullet lodged in the throat and I had to knock it back in the case with a screwdriver to open the cylinder.




the indentation looks deep enough





a new S&W factory mainspring later, no misfires no matter what the weather.

So, on your rifle, not only would I change the firing pin, I would install a new mainspring. Just do it, don't argue.

Then, and lastly, is the end of the barrel peened by firing pin hits? I have not up loaded the pictures, but a Smallbore Prone shooter had his firing pin break, peen the breech, and that caused misfires. Part of the rim swelled into the indentations when they did fire.

So, round versus square: a red herring. What matters is that the rim is hit hard enough, fast enough, and that the supporting rim structure is solid.

 

[1942bull]

My understand in is that rimfire casings are designed so that the primer material become concentrated around the rim with it being parse at the center. That is why rimfire firing pins are designed to strike the edge of the casing. There is no doubt in my mind that the a center firing pin will result in failures when used to fire rimfire rounds.

 

[Texas10mm]

What ammo are you having the problems with?

 

[Speedo66]

Can using a centerfire firing pin on a rimfire model affect ignition?

Only one way to find out for sure.

 

[I6turbo]

Here's a shot of some good rimfire primer strikes. Ideally, the striker doesn't crush the actual thick edge of the rim (because it wastes energy and provides less consistent ignition), but instead strikes just inside the edge of the rim.




Here's another shot showing a primer with a typical factory striker strike on the left, and one where that gun's striker has been modified to a style that is favored by competition bench rest shooters and people looking for the best possible consistency. Note that the edge of the rim isn't crushed by the modified striker on the right.

 

[buck460XVR]

Rimfire firing pins get peened from dry firing for the most part. Comes from steel/striking steel instead of steel striking brass. Problem with a lot of rimfire ammo is that they don't always get the primer compound completely around the rim. The fact that the ammo fires when rechambered and the firing pin hits another spot on the rim, makes me think this too could be the problem or part of the problem.

 

[drband]

I had an old Remington SS .22 rifle that had a round tip FP. Seemed to work just fine. I think the length would be the only issue.

 

[243winxb]

Velocity of the firing pin- clean, remove old built up oils.

Pin protrusion .

Test with different ammo.

Not all rims get primed correctly.

 

[Merle1]

to me if you take out the round, rotate it, and it then goes off - poor primer distribution is the cause.

 

[I6turbo]

My experience tell me that 22 LR ammo is generally pretty reliable, and the huge majority (90%+?) of failures-to-fire in 22 LR is caused by the gun. It's not that the ammo won't fire, but rather that the gun is dirty and the primer strike isn't as strong as it should be, the striker spring is weak, or the gun's striker isn't delivering a "proper" strike. In every case that I can recall over the years where I had a gun that was experiencing several FTFs, addressing the primer strike fixed the problem.

 

[WVGunman]

I really do appreciate the expertise I get in these forums. I went back and looked again at this gun, and I now believe I have multiple problems going on. I don't have a high end cell phone, so visibility in these pics is not up to Slamfire's standard, but check this out the gun's chamber:


I had to fiddle with the lighting to make it even this visible, but the chamber is clearly peened. The peening looks roundish, but check out shells fired by this gun:


Close up, they are neither perfectly square NOR perfectly round. So it looks like overlapping problems to me. The chamber might have been fine or just slightly peened, and then somebody replaced the firing pin with a centerfire pin. After that, a lot of dry-firing peened the chamber. It's also possible this happened in reverse: lots of dry-firing peened the chamber, and somebody replaced the firing pin hoping it was the problem. And they used the wrong pin to boot. The fact that the primer strike is squared off on top and rounded on the bottom makes me wonder if that's not it.
So it looks like I'm going to have the to fix the chamber at least.

 

[WVGunman]

What ammo are you having the problems with?

I've tried 4-5 different types (including .22 Shorts) and it did this with all of them.

 

[danez71]

So it looks like I'm going to have the to fix the chamber at least.

I've sometimes wondered how one fixes that...

I'd replace the firing pin 1st and see if that doesn't fix it.

Ive seen rimfires like that before that were still reliable.

 

[WVGunman]

I've sometimes wondered how one fixes that...
.......

Turns out there was a purpose-built tool for the job called a Menck. It has been discontinued, and other tools available now to do the same thing cost 2-3 times as much! Grrrr .... I've heard it can be fixed with a tapered punch too though, and I have those, so I'll try that first.

 

[Slamfire]

I really do appreciate the expertise I get in these forums. I went back and looked again at this gun, and I now believe I have multiple problems going on. I don't have a high end cell phone, so visibility in these pics is not up to Slamfire's standard, but check this out the gun's chamber:
View attachment 904065

I had to fiddle with the lighting to make it even this visible, but the chamber is clearly peened. The peening looks roundish,
So it looks like I'm going to have the to fix the chamber at least.

Advice on how to fix this was given in this thread:

How to repair peened chamber in .22LR

@Jim Watson referenced the Menck, and I have looked and not found it at Brownell's or Midway.


But there is hope on fleabay:

Menck 22 Chamber Ironing Swage

If you can't fix it with the Menck, then you are going to have to have the barrel removed, squared, extractor cuts redone, etc.

I believe the replacement firing pin was installed by someone who did not allow for clearance between the tip and breech. And that will have to be fixed, peening is a real cause of misfires. It is not going away.

 

[WVGunman]

I believe the replacement firing pin was installed by someone who did not allow for clearance between the tip and breech. And that will have to be fixed, peening is a real cause of misfires. It is not going away.

So, un-peen the chamber AND replace the firing pin? How do I avoid making the same mistake the last guy made, regarding clearance for the pin? Or was that only a problem because he used the wrong firing pin without accounting for the differences between types? I could probably sand off the rounded tip, but I'd be worried about leaving very small burrs, or taking off too much material. Will probably just order a whole new pin as suggested before.

 

[Slamfire]

So, un-peen the chamber AND replace the firing pin? How do I avoid making the same mistake the last guy made, regarding clearance for the pin? Or was that only a problem because he used the wrong firing pin without accounting for the differences between types? I could probably sand off the rounded tip, but I'd be worried about leaving very small burrs, or taking off too much material. Will probably just order a whole new pin as suggested before.

I installed a new Anschutz firing pin on a rifle. I looked to see how far the firing pin stuck out through bolt face, and dry fired the rifle and observed if there was any breech peening. There was not, then I tested it to see if it would go bang. I am not a real gunsmith, so what I did may not be what a professional would do.

 

[HB]

Have you taken the pin out? Its possible the pin is broken in half so it has energy to strike but sometimes everything doesn’t line up to transfer maximum energy. I had a remington pump like that.

Imagine a glancing blow from a hammer to a nail. Its like that with 2 pieces of a firing pin.

 

[Scooter22]

Go to the thread Slamfire posted and DO NOT remove the burr. Ideally you want to push it back into the divot. Good luck.

 

[Pivot Dr]

I doubt the two pins are interchangeable. The bolts are significantly different between rim and center fire. They may indeed look similar but I doubt they’ll interchange. Round pins are not uncommon in rimfires at all. I’m guessing your pin is peened over, your barrel is damaged, your spring is probably weak and with those combinations and maybe thin rims on some shells, and that happens more than you might think and more variation than you probably think, now and then you get a misfire. Fix the pin, the barrel, and get a new spring and your problem will go away. If you can’t find a pin you may have to either build it up and fit and harden it or build a new one, I’ve had to do both.

 

[Bfh_auto]

Advice on how to fix this was given in this thread:

How to repair peened chamber in .22LR

@Jim Watson referenced the Menck, and I have looked and not found it at Brownell's or Midway.


But there is hope on fleabay:

Menck 22 Chamber Ironing Swage

If you can't fix it with the Menck, then you are going to have to have the barrel removed, squared, extractor cuts redone, etc.

I believe the replacement firing pin was installed by someone who did not allow for clearance between the tip and breech. And that will have to be fixed, peening is a real cause of misfires. It is not going away.

I can now check off the I learned something today box.
I always thought you had to face off the barrel and re-chamber to fix firing pin damage.

 

[Shimitup]

My S&W 17 has a round nose pin, I don't think it has ever misfired.