What's this primer trying to tell me?

[Chuck in Indiana]

Hi, folks.. I was working up a load for my model 469, and noticed this. See the half moon on the edge of the primer strike? Looking at it through a 10X glass it looks like something is sliding to put the half moon in there. Does my explanation make sense?

 

[David R]

I see nothimg

 

[arjay]

That is odd,no idea what caused it.

 

[leeloader]

Try pushing out the firing pin to examine for damage past the tip. Does it happen on all of them? As you know, the striker hits the primer, bang pushes out the primer partially and is reinserted. If the striker hits the primer again during that process, there could be something as simple as a already designed larger chamber and this has been there all along. Would be interesting to hear the final resolve.

 

[Yorkie Man]

If you are talking about the smudge at the left of the primer in your picture that is from the slide moving down after the round was fired. I have seen that on most of my center fire pistols regardless of make. The bullet has cleared the muzzle and the mark is at the top of the cartridge as it is moving out of battery.

 

[Chuck in Indiana]

Try pushing out the firing pin to examine for damage past the tip. Does it happen on all of them? As you know, the striker hits the primer, bang pushes out the primer partially and is reinserted. If the striker hits the primer again during that process, there could be something as simple as a already designed larger chamber and this has been there all along. Would be interesting to hear the final resolve.

No, it doesn't happen on all of them. I've just noticed it, though. I'll go back through some of my brass from different loads and see if I find it.

 

[rwsmith]

I can't see it, but......

From what you describe it sounds like the firing pin is slightly off center when it first touches the primer, and centers itself as it penetrates. I'd suspect the pin/bushing fit. Or maybe the cylinder moves a little when the pin is on its downward strike? This is only speculation on my part. I'm just throwing out ideas. Probably someone will be able to answer this right off. This may be more of a smithing problem.

 

[Rule3]

I see nothimg

I know nothing

Do all the primers look like that?, does a factory ammo round look like that?

Could just be the firing pin. Maybe you have one of the new NSA DHS Id firing pins?

 

[Murphy's Law]

My two cents, nothing wrong and quite normal for most center fire hand guns.

 

[Iggy]

Could be a weak firing pin spring.The pin is not returning before the case is starting to be ejected and dragging on the primer.

 

[mikld]

Definitely no apparent problem. Have you considered "firing pin swipe"? Happens when the shell is being ejected and the firing pin is still in contact with the primer and makes a slight "gouge" in the soft primer cup. Nuttin' to worry about (especially if one needs a 10x magnifucation to see it!).

 

[moosedog]

Looks good to me. If it goes bang every time, that's what counts.
Very few primer strikes are perfectly centered.

 

[Chuck in Indiana]

Could be a weak firing pin spring.The pin is not returning before the case is starting to be ejected and dragging on the primer.

Hmmm, I like the sound of that.. when you look at it under a magnifier, that's a possibility. Maybe the firing pin is just dirty? I've had this gun since new, and just started to shoot it again after a 30 some year hiatus.

 

[Aticus]

Hmmm, I like the sound of that.. when you look at it under a magnifier, that's a possibility. Maybe the firing pin is just dirty? I've had this gun since new, and just started to shoot it again after a 30 some year hiatus.

Bingo! Your firing pin's not retracting fast enough. Pull the firing pin or at least blast some Gun Scrubber down the channel and then some air to dry it. A couple drops of oil to lube it will work wonders.

 

[Chuck in Indiana]

Bingo! Your firing pin's not retracting fast enough. Pull the firing pin or at least blast some Gun Scrubber down the channel and then some air to dry it. A couple drops of oil to lube it will work wonders.

Ding ding ding.. I think we have a winner..
I'm a revolver guy.. where do I find a manual for disassembly?
TIA

 

[Rule3]

If it is the firing pin and spring, clean it yes, but do not oil it. Oil will just collect more dirt. If you just have to squirt something in there use spray silicone.

 

[Chuck in Indiana]

Just loaded a few more, and the easy way apparently isn't the answer. Sprayed some cleaner in there, blew it out..3 out of 5 did it. It's no big deal, I suppose.. but I checked some other brass that I'd shot, and even some military ball, and some did it. I only noticed it because I was getting up to a max load, and was looking pretty hard for pressure signs. When I find a manual, I'll tear it down and clean it up.
Thanks!

 

[lebomm]

How 'bout this? As the recoil begins, the firing pin may still be protruding a bit, or with an inertia f.p., reenters the strike as the slide begins to recoil. As the barrel drops to unlock, the tip of the f.p. makes that "swipe" at the edge of the strike. Again, given dependable function, not a problem you need to do anything about.

Larry

 

[alwslate]

It is no doubt a firing pin swipe, several explanations describing the
same cause above. It's not a "problem" and you're not going to fix it.
This is common in various centerfire autos and is very obvious with
primers of ammo fired in Glocks. It happens even with low pressure
rounds like .32 and .380 acp sometimes.

 

[blujax01]

Ding ding ding.. I think we have a winner..
I'm a revolver guy.. where do I find a manual for disassembly?
TIA

Oh just start ripping into her and you'll figure it out! But do it under a blanket, those springs are way too frisky and hard to chase down...

Seriously, Author Jerry Kuhnhausen "The S&W Revolver - A Shop Manual" costs less than $30. Or you can take your gun to any reputable gun shop and they'll charge you about $30 to clean it.