Firing pin appears to be piercing primer

[RB II]

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.

 

[RegionRat]

Load or pressure details?

 

[338 dude]

Try a magnum primer CCI 450.

 

[quigley257]

New rifle? You may have to get the firing pin bushed or send back to manufacturer. Are you using data that was developed with a different brass maker? Alpha brass is known to have smaller internal dimensions compared to others. If you're loading a charge that was okay in a different case, it may well be too hot in the Alpha brass.

 

[cajun]

Is this an AR ? Edit I see this is not. The 400's have soft cups. I would try 450's if it's not a load issue.

 

[d11r529]

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

 

[RB II]

Try a magnum primer CCI 450.

Is this an AR ? Edit I see this is not. The 400's have soft cups. I would try 450's if it's not a load issue.

Thanks for the responses.
This is small rifle primer brass. So magnum primers wouldn't work as far as I know.

 

[RB II]

Load or pressure details?

103 ELD-X loaded at .020 off of max COAL. Max loaded was 42.5 of H4350. No pressure signs.

 

[Dmagna]

I'm not a huge fan of book data but you are above load data from hornady. What speed are you at?

 

[wasskeet]

Thanks for the responses.
This is small rifle primer brass. So magnum primers wouldn't work as far as I know.

CCI 450's are magnum small rifle primers - w/ thicker cup

CCI 450 Small Rifle Magnum Primers

CCI Small Rifle Magnum Primers - 1000ct Box

www.bluecollarreloading.com

 

[Sealesniper]

As stated, could be pressure. Try a lighter load and see if you have same results. Not all chambers and barrels allow max loads, plus jump can contribute. Easy solution is shoot factory load and see if primer is pierced. If not, not a firing pin issue as it has same strike all the time. If factory not pierced, your load is too hot.

 

[SupressYourself]

103 ELD-X loaded at .020 off of max COAL. Max loaded was 42.5 of H4350. No pressure signs.

Piercing primers is a pressure sign. Your load doesn't look crazy, but is a hair over Hornady book max, and their data is using Hornady brass, which likely has more capacity than Alpha.

Back off your load a bit and / or switch to a harder primer like CCI 450 or BR4.

Whatever you do, don't keep piercing them. The escaping gas can pit your bolt face.

 

[Critter Picker]

After the pierced primers,if it was my rifle I would check the firing pin for gas cutting. I would also switch to magnum primers. If you are over pressure, why?

In my mind you have to solve that riddle. I have a 6BR that had that problem. Turned out to be brass with less capacity.

Could be bolt that needs a bushing,which was stated earlier.

 

[338 dude]

Thanks for the responses.
This is small rifle primer brass. So magnum primers wouldn't work as far as I know.

Small rifle magnum they have a thicker stronger cup.