Firing pin appears to be piercing primer

[Seabeeken]

There is some bolt swipe on the brass but whether or not its pressure or a sharp edge on the bolt I dunno. I'd get the firing pin looked at also since it could be gas cut which can make piercing more common. As mentioned, this could also be from too much firing pin protrusion. Magnum primers might resolve the problem but be sure to check the firing pin point for gas cutting from the blown primers.

 

[ncwg2boatguy]

There is some bolt swipe on the brass but whether or not its pressure or a sharp edge on the bolt I dunno. I'd get the firing pin looked at also since it could be gas cut which can make piercing more common. As mentioned, this could also be from too much firing pin protrusion. Magnum primers might resolve the problem but be sure to check the firing pin point for gas cutting from the blown primers.

"Construimus, Batuimus" is definitely pointing you in the right direction

 

[243winxb]

CCI 400 primers.

Wrong primer for pressure above 40,000 PSI.

 

[Dean2]

This is what a bolt face looks like after someone is imprudent enough to fire multiple rounds that pierce the prime. Notice the burn out around the primer and the flame cuts on the face.

This is what that same bolt face is supposed to look like.

 

[Dean2]

Wrong primer for pressure above 40,000 PSI.

^^^^^ Spot on with the older version of the 400. The ones made the last 7 or so years have thicker cups now, so it depends on the age of those 400s.

 

[Critter Picker]

This is what a bolt face looks like after someone is imprudent enough to fire multiple rounds that pierce the prime. Notice the burn out around the primer and the flame cuts on the face.


View attachment 640373

This is what that same bolt face is supposed to look like.

View attachment 640374

Great comparison! Also looks like a lot of flame cutting on plunger.

 

[Dean2]

Great comparison! Also looks like a lot of flame cutting on plunger.

You are exactly right, it flame cut there too. This is going to be no fun to clean up and get the head space correct, on a rifle with a fluted barrel.

 

[UncleDano]

I had the same problem, took it to my gunsmith and after taking measurements he took it to a sanding belt. Don't know how much he shortened it but I haven't pierced a primer since. by the way it's a Remington 700

Shortened what?

 

[lyle2231]

6 Creedmoor. Firing pin appears to be piercing primer. No misfires, just trying to understand what is happening/why.

7 brass on left of pic. Adjacent rows fired from same rifle.

Unsure of exactly the sequence of the issue but fairly certain not consecutive and not the last 7 rounds fired from the rifle.
1x Alpha SRP brass and CCI 400 primers.
Fierce Carbon Rival rifle.
Thanks in advance.

Firing pin protrusion gauge might reveal something? Just sayin

 

[RB II]

Thanks for all of the information and comments. All constructive toward finding a resolution to this issue as well as educating me on this reloading circumstance.

The rifle and brass will go to the gunsmith next week for complete inspection.

All of the loads were for load development, so no residual remains. I will start over completely with the load development.

The load for this rifle that resulted in the damaged primers was 3 shots chrono'd with a Garmin at 3110 fps average with 42.5 of H4350.
The Hornady load data on the 103 ELD-X, basically their "red" load is 43.9 grs H4350 with 3150 fps.

In any case, it appears that this load at 42.5 is too hot for those primers in this rifle. Unless there is a mechanical issue which I will get resolved next week.

 

[skipglo]

I finally read a posting to the end ( I think) and haven't seen one on ES and SD. 3 shot average.
..isn't an average of 50 loaded rounds...hit and miss blown primers in the box shown 1) definitely speak to overpressure but 2) why only certain shells? I'd take a close look at your ES and SD as well.....just me Edit: Ex: 3110 fps + 3610 fps + 2610 fps ÷ 3 = 3110 average at which can = hit and miss blown primers

 

[lyle2231]

Thanks for all of the information and comments. All constructive toward finding a resolution to this issue as well as educating me on this reloading circumstance.

The rifle and brass will go to the gunsmith next week for complete inspection.

All of the loads were for load development, so no residual remains. I will start over completely with the load development.

The load for this rifle that resulted in the damaged primers was 3 shots chrono'd with a Garmin at 3110 fps average with 42.5 of H4350.
Attached is the Hornady load data on the 103 ELD-X, basically their "red" load is 43.9 grs H4350 with 3150 fps.

In any case, it appears that this load at 42.5 is too hot for those primers in this rifle. Unless there is a mechanical issue which I will get resolved next week.

May I suggest…. Send your load work up notes, powder, grains type, cartridge OAL. Weigh 3 case's for a rough average weight. In my own experience I have a 6Br barrel that over pressures using the "if gun won't shoot these" loads. I went to the Sierra book used their load map. Stopped at the accuracy load. I surmised that my barrel was perhaps "tighter"
than what was tested.. HTH.

 

[lyle2231]

I finally read a posting to the end ( I think) and haven't seen one on ES and SD. 3 shot average.
..isn't an average of 50 loaded rounds...hit and miss blown primers in the box shown 1) definitely speak to overpressure but 2) why only certain shells? I'd take a close look at your ES and SD as well.....just me Edit: Ex: 3110 fps + 3610 fps + 2610 fps ÷ 3 = 3110 average at which can = hit and miss blown primers

Occasionally speed isn't always what a rifle likes. Just my 2c

 

[RB II]

I finally read a posting to the end ( I think) and haven't seen one on ES and SD. 3 shot average.
..isn't an average of 50 loaded rounds...hit and miss blown primers in the box shown 1) definitely speak to overpressure but 2) why only certain shells? I'd take a close look at your ES and SD as well.....just me Edit: Ex: 3110 fps + 3610 fps + 2610 fps ÷ 3 = 3110 average at which can = hit and miss blown primers

The three speeds on the 42.5 load were 3139, 3166 and 3133= 3146 avg (obviously I misread a note on the avg speed being 3110)