Strange looking primers

[chboats]

What would make primers look like this. They were shot in a 9mm 1911. The load in 3.5gr of Red Dot under a 125 gr boolit. They look like the firing pin dent was pushed back out then flattened back. The primers are CCI SPP

I fired about 20 rounds before I notice the primers. All of the fired casings looked like this.

Carl

[paul h]

Soft primer cups or a light weight firing/pin striker.

[Mytmousemalibu]

My guess is a fairly large firing pin hole and the pin crater is blowing into the hole and as the slide reciprocates and the lockup disengages, the brass is hard against the breechface and since the barrel drops as it unlocks, the pin hole is shearing the crater flat, hence the nickel plating is gone too. Primers aren't showing extreme pressure signature but it looks warm enough. I have seen quite a bit of brass from 1911's and 2011's with the pin crater blown back out but not sheared off. Your gun might have a pretty sharp edge on the pin hole. Check it for brass & nickel shavings. The newer CCI's I have heard are softer than they used to be which might be the partly why it looks like this and light springs possibly. 3.5 of Red Dot behind a 125gr doesn't sound bad without looking at a book. Is the charge within SAAMI spec? Bullet size not too large for your bore?

[chboats]

Mytmousemalibu
The firing pin hole doesn't look that large but your explanation of the way it seems to sheared seems right. I'm going to try different loads to see what happens. I don't think the loads are very hot because the brass lands on the bench beside me.

thanks
Carl

[slughammer]

Probably a titanium firing pin. The lighter mass allows the return spring to retract the pin too early in the pressure curve. Springfield Armory does this to pass a drop test. I had one and solved it by installing a steel firing pin.

[bouncer50]

All the answer you got so far are good. I been reloading for over 30 years check what other have written is a good start for you answer.

[toallmy]

I had a 1911 Springfield 9 mm doing what seams like the same thing earlier this year and even got worse started getting misfiring do to light primer strikes , I replaced the main spring that took care of it . Try the pencil firing pin strike test .

[GhostHawk]

I have gone up as much as a full 4.5 grains of Red Dot behind a 125 gr boolit with no pressure signs. So pretty much it is 100% the gun causing this. I think you have gotten good advice.

[Dusty Bannister]

Any of you having issues with the firing pin being jammed forward by the brass shavings blocking movement of the firing pin after it contacts the primer? That could be pretty exciting and might be something the OP would want to carefully check before continuing to use this load and primer combination.

[slughammer]

I've had the little brass donuts cause light strikes and failures to fire. Fixed it before it had a chance to get more exciting.

[Tackleberry41]

Gets bad enough, it will end up with the metal from the primer blocking the firing pin hole. I have been having the same issue with primers in my 1911, running 7.62x25. Its a 40 cal slide, w 9mm/40 extractor and the 9mm firing pin.

[chboats]

I had never seen anything like this in over 30yr of reloading and casting. This my first experience with a 9mm.
I will try the steel firing pin because that is very easy to change. If that doesn't solve it will go to a heaver main spring.
Thanks for the help will keep you posted

Carl

[toallmy]

Your main spring may be binding , or rubbing on something .

[slughammer]

If the mainspring was causing light strikes I would expect some failures to fire with CCI primers. The 1911 has an inertia firing pin. A titanium firing pin weighs 30gr which is only half as much as a steel pin at 60gr.

[Plate plinker]

Does it do it with all brands of primer?

I do not have this problem with my Springfield 1911 9mm.

[rond]

What would make primers look like this. They were shot in a 9mm 1911. The load in 3.5gr of Red Dot under a 125 gr boolit. They look like the firing pin dent was pushed back out then flattened back. The primers are CCI SPP

I fired about 20 rounds before I notice the primers. All of the fired casings looked like this.

Carl

Timing is off, barrel is unlocking from slide to soon. A stronger hammer spring may slow it just enough or you may need a different barrel link.

[avogunner]

I was shooting my S&W M&P .40cal this weekend and had several failure to fires (5gr Win 231, Rem 1 1/2 SP primers, Lee 401-175-TC). Looking at the rounds that did fire, the primers looked EXACTLY as the ones shown here so my first thought was weak hammer strikes, but after reading the responses I'm not so sure. I'm hoping it's a simple case of crud in the firing pin chamber and a good cleaning there will be my first course of action.

I too have never seen this in my 30+ years of reloading and the timing of this thread was uncanny! For the OP (and others who have experienced the same) if you've solved it, please update.

Thanks
Semper Fi

[slughammer]

Think about the pressure cycle and how a primer dent is actually formed. The high pressure part of the cycle occurs while the firing pin is extended and the primer is formed around it. Then pressure lowers and the firing pin retracts leaving the indentation.
If the gun unlocks too early in that cycle the firing pin will still be extended into the primer and you will get drag marks. (This could also come from a weak return spring failing to retract the pin)
At NO POINT should the primer be flowing into the firing pin hole. The firing pin needs to weigh enough and be driven fast enough into the primer to (A) make it go off and (B) it needs to stay there during the peak parts of the pressure curve.
A harder strike with a pin of sufficient weight will cure this in a 1911.
For the M&P we would need to know if all the gun is factory stock. It doesn't link up the same way as a 1911 and the recoil spring plays a bigger part in holding the slide into battery. And the striker spring gives the striker it's force.
For either the 1911 or the M&P we need to make sure that the rounds will pass the plunk test into the barrel to eliminate the chance that the ammo is holding the slide slightly out of battery and taking some of that strike energy to close.

[chboats]

slughammer - Thanks for the explanation. Several other gave suggestions that point in this direction. I currently have on order a steel firing pin to replace the titanium pin and a stronger main spring. hopefully this solves it. Will keep you posted

Thanks
Carl
Carl

[Ballistics in Scotland]

My guess is a fairly large firing pin hole and the pin crater is blowing into the hole and as the slide reciprocates and the lockup disengages, the brass is hard against the breechface and since the barrel drops as it unlocks, the pin hole is shearing the crater flat, hence the nickel plating is gone too. Primers aren't showing extreme pressure signature but it looks warm enough. I have seen quite a bit of brass from 1911's and 2011's with the pin crater blown back out but not sheared off. Your gun might have a pretty sharp edge on the pin hole. Check it for brass & nickel shavings. The newer CCI's I have heard are softer than they used to be which might be the partly why it looks like this and light springs possibly. 3.5 of Red Dot behind a 125gr doesn't sound bad without looking at a book. Is the charge within SAAMI spec? Bullet size not too large for your bore?

Yes, I'm sure you are right about how that flat yellow patch is created, and the reason it looks different from other pistols' extruded primers. But the firing-pin and hole are probably the size the manufacturer made them, and beg the question why they aren't all like that. I think it is likely that overpressure simply wasn't enough to detach the central piece and project it down the hole out of reach of shearing. Other possibities are particularly tenacious brass which doesn't permit detachment, or some unknown factor permitting a slow fire, too quick to be noticeable, unless you are one of those people who always hit the bullseye, but slow enough to let the firing-pin bounce and give it no support.