Pierced Primers

[vossman]

When I took the gun apart I looked at the firing pin to to see if it was sharp and it looked normal to me. Nice smooth round edge, nothing special. Today was the first time I shot it, put 40 PMC factory rounds through it then all 40 of the reloads through it. I shot one or two reloads by themselves to make sure they'd cycle first.
Did not check the case mouth dimension. I know I could not press a bullet in there by hand when I tried. I know I can now that they have been fired though. I will load up some dummys and see what I come up with. Thanks. V

[clocker]

Take it for what it's worth, but I don't see the other signs of over pressure on those cases. That leads me to suspect that your firing pin is out of spec or the primers are too soft. If you can find a different brand of primer, I'd try that as a next step in troubleshooting.

[rpm]

How are you loading these? I've noticed on some brass (PRVI Partizan in particular) that it requires significant force on my 550 to seat the primers to the proper depth, despite having been through the swager.

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[eneranch]

How are you loading these? I've noticed on some brass (PRVI Partizan in particular) that it requires significant force on my 550 to seat the primers to the proper depth, despite having been through the swager.

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I'm thinking that's probably NOT a good thing!!

[vossman]

I took my time with these. Tumbled, hand primed, single stage press, swaged primer pockets. Primers seated normally just below flush after swaging. SW didn't have any other SRP other than the Remington I am using so I will try again at a lighter load.
Remingtons are supposed to be pretty soft from what I understand, CCI and Tula are at the top of the hardness scale. I need to find a few of those or maybe some magnum primers.

[vossman]

Just as an update. I loaded some more rounds with these primers for my Rem 700 in .223. 24.5 grains of Varget and a 55 FMJ Hornady V-Max bullet. 1 more pierced primer out of 25 rounds. I have not pierced any other primers with this rifle with probably 500 rounds thru it. I think its time to call Remington and see what they say.

[Hoser]

Check your firing pin tip. It most likely has a sharp edge on it and when pressures go up they pop.

26 gns is not hot for Varget. I run out of room in the case before I run into pressure issues.

[sabot_round]

Check your firing pin tip. It most likely has a sharp edge on it and when pressures go up they pop.

26 gns is not hot for Varget. I run out of room in the case before I run into pressure issues.

I doubt that two different rifles have the same issue. I think those Remington primers are the culprit.

[vossman]

Remington sent me a shipping label an I sent them 2 of the cases with pierced primers. I will post if I hear back from them.

[RTillery]

Sounds to me like you could possibly be setting the shoulder back on your cases too far during resizing causing a headspace clearance. Getting your resize die set to the length of your chamber is a basic first step. If you have it screwed down to your shell holder, and the die is on the short side, and your chamber is on the long side, you may have a head space situation. Even if your chamber checks out perfectly with a headspace gauge, If you push your shoulder back on your case, you have excess headspace. What happens is the case is driven forward into the chamber by the firing pin, and there is clearance between the bolt face and rear of the case. When it fires, the brass grips the chamber, but the primer is pushed rearward by pressure in the case to fill the void. The firing pin is forward and the primer flows around it, punching a hole. Then the case stretches back to the bolt face flattening out the primer. Not to worry too much though, this is not that uncommon. A way to check is to fire a factory load and see if there is any signature on the primer. We measure this all the time in benchrest. We have a little tool we call a 'gizzie' usually made by the smith that chambers the barrel, that slips over the neck and registers on the shoulder. You take a fired case ( It is now the length of the chamber) and resize it as follows: Measure it with your gizzie, back off your resize die a 1/2 or 3/4 a turn from your shell holder. Resize and remeasure with the gizzie. It will probably have grown in length slightly. Screw the die down just a smidgen and try again until our measurement is just a thousands or two shorter from where we started with the gizzie. The round should chamber and you will have minimum headspace and maximum brass life. You can do this without the gizzie by just sizing and trying it in your chamber til the bolt just closes but it is harder to tell when you have it just right. We sometimes reload our PPC cases a hundred times or more so getting headspace set correctly is an art form. The object is to just barely kiss the case all over to create the slightest clearance possible and still chamber without drag. Getting your chamber dimension and your resize die "married" makes life good. I have seen three guns blown up because of having it wrong. Not pretty!! Good luck.