9mm pierced primers

[HighRoadRover]

Good discussion -- different ways to come at the problem, but I would probably order another firing pin (striker) and shorten the one in the P320 a little bit just to see what happens next. The debate on "too much powder" would be mooted if there are no more pin-holes in the primers after shortening the firing pin a tad bit. Alternatively, I'd try this ammo in a different pistol, so see what happens there. Or maybe try that too!

I'm counting on the OP continuing this investigation and passing along the results!

 

[243winxb]

Wrong primer- 9mm runs at magnum pressures. Thicker cup on mags?

https://saami.org/technical-information/ansi-saami-standards/

SAAMI psi for 9mm is 35,000 & 38,500 for +P. The 357 mag is 35,000.

Win chart.

(I just woke up and remembered why i use magnum primers in handguns.)

 

[Slamfire]

Good discussion -- different ways to come at the problem, but I would probably order another firing pin (striker) and shorten the one in the P320 a little bit just to see what happens next. The debate on "too much powder" would be mooted if there are no more pin-holes in the primers after shortening the firing pin a tad bit. Alternatively, I'd try this ammo in a different pistol, so see what happens there. Or maybe try that too!

I'm counting on the OP continuing this investigation and passing along the results!

I would be interested in reading the results, to include, if the number of misfires increase after shortening the firing pin.

 

[Rule3]

Update w pictures and to answer questions. I went to the range today and shot 100 wsp and 50 cci's. The cci's were actually .2 gr hotter (5gr). This resulted in 3 pierced primers in the wsp flavor. I am using a new sig p320 xcarry. The reason for the short coal has been answered in previous posts. The primer pockets had the crimps removed w/ a dillon super swage 600. I do not clean primer pockets other than removing crimps from mil brass. I do check for high primers, they are seated just below flush, i use a handheld priming tool. If there was any confussion, the primers were not loose at all, before or after firing. It was noted today the brass was just clearing my shoulder. I believe my next step is to drop down to a 4.4 charge and see if that results in piercings. According to my notes 4.4 seemed weak but it did work the action and locked the last round to the rear. The 3rd picture contains the pierced primers in the middle.
View attachment 852777 View attachment 852778 View attachment 852779

Here is a novel idea. Why not try loading some new or once fired brass of all the same headstamp. ?? That does not require crimp removal??

What 9mm brass are you using that requires removing a crimp. Hard to tell from you picture but some looks like NATO brass and others regular commercial brass.

My guess is the crimp is not remove properly. REAM them out.

 

[Charlie98]

My guess is the crimp is not remove properly. REAM them out.

He did... he used the Dillon swager. In my experience, if you can seat the primer in the first place, without obvious force, you are good.

After looking at the OP's photos, I'm kind of wondering about the length of the firing pin, too...

 

[Okcafe86]

Ok. I do want to point out in the picture, I know its difficult to see, that the pierced primers are in commercial brass here. 2 winchester commercials and 1 r&p. As far as using magnum primers here....Ive never seen that in a 9mm reloading book. Not saying it doesnt exist, I just havent seen it. Before my next trip to the range I plan on shortening the firing pin .002 - .004. Also I will be bringing a different pistol to compare. We shall see. Also....thank you for all the comments, I do request if you have input particulatly harsh input, you read the post in its entirety. Many questions and items have been covered already.

Edit: if it was missed earlier, I already ordered another firing pin, actually the entire striker assembly incase i ruin this one.

 

[ATLDave]

Update w pictures and to answer questions. I went to the range today and shot 100 wsp and 50 cci's. The cci's were actually .2 gr hotter (5gr). This resulted in 3 pierced primers in the wsp flavor.

So the 50 CCI's did not show pierced primers?

 

[Okcafe86]

So the 50 CCI's did not show pierced primers?

Correct

 

[ATLDave]

OK.

I am highly skeptical that the pierced primers have anything to do with swaging nor primer pocket cleanliness (or lack of same) nor brand of brass (though it's always nice to be dealing with headstamp-sorted brass as a way to take out a variable). Nor do I think it is necessary to run magnum primers in most 9mm loads. In fact, I use CCI SPP (non-magnum) in my 9mm Major loads for my racing gun without cratering or other primer failure. And I frequently use WCC brass.

I still suspect something is up with the nose of the firing pin. The primers in the photos do not look flat. Typically one would expect primers to flatten quite a bit before they failed (pierced) due to a true over-pressure issue. A batch of bad/defective primers is also possible, though a true component defect is rarely the issue. Different primers are suitable for different applications, though, and it's possible that the firing pin of this particular gun is just too hard on primers to permit the use of WSP's.

ETA: To be clear, I am not a proponent of "primer reading" as the primary method of staying safe in reloading. I haven't carefully studied the length/capacity issue here. Maybe someone will come along with a Quickloads calculation on what the load data and seating depth is likely to be doing in terms of pressure. I am just saying that, if the OP is comfortable based on the book data with his load, there are explanations other than "too much powder" for the pierced primers.

 

[Texas10mm]

Wrong primer- 9mm runs at magnum pressures. Thicker cup on mags?

https://saami.org/technical-information/ansi-saami-standards/

SAAMI psi for 9mm is 35,000 & 38,500 for +P. The 357 mag is 35,000.

Win chart. View attachment 852819

(I just woke up and remembered why i use magnum primers in handguns.)

Huh? Lots of pistol rounds operate in that pressure range and don't require magnum primers.


9mm is VERY sensitive to bullet seating depth. On NATO spec ammo seating the bullet 0.3" deeper can more than double pressure.

 

[Rule3]

Ok. I do want to point out in the picture, I know its difficult to see, that the pierced primers are in commercial brass here. 2 winchester commercials and 1 r&p. As far as using magnum primers here....Ive never seen that in a 9mm reloading book. Not saying it doesnt exist, I just havent seen it. Before my next trip to the range I plan on shortening the firing pin .002 - .004. Also I will be bringing a different pistol to compare. We shall see. Also....thank you for all the comments, I do request if you have input particulatly harsh input, you read the post in its entirety. Many questions and items have been covered already.

Edit: if it was missed earlier, I already ordered another firing pin, actually the entire striker assembly incase i ruin this one.

OK the primers are bad, could not be anything with the reloader or the gun. All OK now??
As with most issues it is all speculation as we are not there.

As with any trouble shooting start with the easiest simplest things first.

By using new or newish brass that doesn't involve swagging (or reaming which is different) you can pretty much eliminate a brass issue.

Then move on to proper seating of the primers. Then eliminate that

OR just jump right to the more difficult costly method of messing with the firing pin

Good Luck

 

[243winxb]

I plan on shortening the firing pin .002 - .004.

Please dont.

Firing pin protrusion is different between makes , models and types. From around .030" to .055" on some. Not all. An inertia firing pin (not yours) is different.
Plus the 9mm head spaces on the case mouth, unless the extractor stops forward movement from the striker/firing pin. This leaves a round loose in the chamber. So imo, .004" shorter is not going to make a difference.

This may be as simple as a bad batch of primer.

 

[Zendude]

Going back to the pressure issue for a sec...
Wouldn’t using LRN produce higher pressure than a FMJ? LRN is larger in diameter than FMJ and can create a better gas seal. Maybe check the bullet diameter. If they are inadvertently sized for 38 special then the diameter might be upwards of .358”.

 

[Texas10mm]

Going back to the pressure issue for a sec...
Wouldn’t using LRN produce higher pressure than a FMJ? LRN is larger in diameter than FMJ and can create a better gas seal. Maybe check the bullet diameter. If they are inadvertently sized for 38 special then the diameter might be upwards of .358”.

Lead bullets create less pressure since the lead is easier to deform and slicker in the barrel.

Lyman did a test using bullets sized up to 0.006" over bore. The pressure was the same.

I size all my 9mm bullets to .357 with no problem. I have used .358 in the past.

 

[Okcafe86]

Im interested to see if my p89 experiences pierced primers. Ill keep this thread updated.

Curse at me if you will, i just took .009" worth of material from the tip. I did a super scientific test by chambering a dummy round and putting a piece of paper on the breech face and pulling the trigger. I got a nice hole. I will go to the range soon and see if that stopped piercings, and if it starts ftf. This will be alongside my other pistol shooting too. As stated earlier I have a new firing pin in the mail if this one is ruined. I enjoy doing this stuff, my wife always tells me Im looking for problems to fix.

 

[Steve in NC]

The posts above have covered the pressure side and possible firing pin issue pretty well. Just a little perspective on WSP primers and their strength.

I messed up last year while reloading a large batch of 556 ammo. For the last 600 rds I accidentally used WSP instead of WSR primers with 25gr of Benchmark under a 50gr bullet in military brass. I realized my mistake while updating my reloading spreadsheet database and the lot# didn't show up properly. So that is when I discovered the use of the WSP instead of WSR primers for those 600 rounds of ammo.
So those were put aside and I only fire them in my rifle and don't let anyone else shoot them. I've fired probably 200 of those 600 rounds. I get the same pinhole in the bottom of the firing pin indent in the fired primer on approx 30% of those rounds. They don't truly pierce the entire firing pin indent. Just a black pinhole at the bottom. That means 70% of these pistol primers hold the pressure of a 556 without an issue. Here is the Winchester assigned Lot# of those primers: Win WSP, Lot#: EAL055G

Also, My firing pin on my AR is .001 over the min spec for an AR firing pin protrusion measurement.

This isn't to say that the primers the OP used should act the same way. Just giving an example of how much pressure they really can hold. And I definitely can't say his primers aren't defective either. Just pointing out that pistol primer cups are not necessarily as weak as we might believe them to be. I've had 2 bad batches of Federal primers in my competitive shooting over the years to where they simply leaked out the edge of the primers and burnt the heck of out of my bolt face and blew gas and crud into my face. And no it wasn't an over pressure issue in either instance. There was just a big burnt hole in the corner of the primers. ALWAYS wear safety glasses!! The one set of glasses I was wearing during the 2nd incident was speckled with marks from the tiny pieces of brass and/or steel that came out. Felt like somebody blew a sand blaster in my face for a 1/2 sec. Federal paid to have the bolt fixed and also threw in a 1000 new primers.

 

[rfwobbly]

I shoot BE-86 in my 9mm at an OAL of 1.100" and recorded 1071fps on a 124gr jacketed PD bullet. 5.1gr got me 1093fps in the same test. 5.0gr is not too much, but for plinking I much prefer 4.9gr which averages 1053fps.

 

[Nature Boy]

Perhaps we are talking at cross purposes, and ignoring what we don't want to hear.

Perhaps in the future you speak for yourself and let me speak for me. That’s common courtesy

You should know better

 

[Average Joe]

Here's a twist. I loaded some .357 magnums with 7.0 grains of BE 86 (max load per Alliant is 8.1 grains a with 158 grain bullet) I started getting pierced primers, and they were S&B primers..... Never had that problem before with this gun, so I switched powders and the problem went away.... just saying.......

 

[tightgroup tiger]

I'm wondering about how far out of center the strikes are with the firing pin. The farther away from center the farther away the high point of the primer anvil is.
There is nothing under the cup where the firing pin hits, to support the cup. So the cup may be getting dimpled more if the firing pin was in the center.
Have you tried your other pistols with the same ammo yet?

 

[Charlie98]

Here's a twist. I loaded some .357 magnums with 7.0 grains of BE 86 (max load per Alliant is 8.1 grains a with 158 grain bullet) I started getting pierced primers, and they were S&B primers..... Never had that problem before with this gun, so I switched powders and the problem went away.... just saying.......

Interesting... What kind of pistol were you shooting those in?

Have you tried your other pistols with the same ammo yet?

I think the OP is fixing to, next.

 

[Rule3]

Think of the "odds" or probability if X number of primers get pierced out of 50. I think somewhere the OP said 3 in a later post.

Why would only 3 or 4 out of 50 be "bad"?? Modern production packs a gazillion primers in minutes. So just a few out of 50 or thousands are defective?? Wouldn't they all be bad?

 

[Okcafe86]

Update. Went to the range today and shot 200 wsp loads. This is after me removing .009" from my firing pin tip. I had no pierced primers and no ftf, 100% reliability. The primer strikes cover more surface area but look just about as deep, maybe just a little shallower. They look like excellent strikes though. Comparing before and after it looks like the firing pin may have been a little sharp/narrow at the tip. I was planning on stopping and switching guns on my 1st pierced primer, but that never happened.

 

[Dudedog]

Hopefully you have the problem solved.

 

[243winxb]

removing .009" from my firing pin tip

What ever works i quess.