Never seen a primer do this before.....

[waveslayer]

On a side note, have you looked at pointing those bullets? I got a pointing Die and it increased my BC's by 4% or more on some loads... Just a thought when I saw your pictures.

Also, on the primers, your loads are too hot. So much high pressure that the case rams against the bolt face so fast the firing pin doesn't have time to move...

 

[25WSM]

The firing pin isn't supposed to move. If it did you would blank every primer you shoot. That's why a weak firing pin spring will cause this. If your firing pin went back in When you shoot your primers would not have a dent in them. The pressure would blow the sent back out. That is why a weak pin spring will blank. The pressure on the primer overcomes the resistance of the pin and pushes into the firing pin hole with no support it breaks around the indentation. Yes his loads are warm or his firing pin fit is loose. I've had Remington with loose fit crater on even the lowest loads. So craters are only reliable indicators of pressure when the firing pin fits right. Shep

 

[25WSM]

But excessive head space will cause it like Waveslayer says because the case head moves back so much so fast it can pierce. Shep

 

[bigedp51]

You are using a small rifle primer with a cup thickness of less than .025, and possibly .019 in thickness, and a large rifle primer has a cup thickness of .027. Meaning as stated you need to change primers that have a thicker .025 thickness cup.

Below is a CCI 400 primer with a cup thickness of .020 that was fired in a AR15. If you have a firing pin on the long side and bump the case shoulder back too far the primer backs out of the primer pocket and the firing pin punches the center of the primer out. Meaning when the primer backs out after being hit the firing pin acts like a cookie cutter and pushes the center of the primer out.

So switch to thicker primers made for higher pressure cartridges and not thinner primers made for the lower pressure .22 Hornet. You are basically using a thinner pistol primer in a higher pressure rifle round.

Read the link below.

CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
http://www.sksboards.com/smf/index.php?topic=56422.0

"Cases that utilize small rifle primers and operate at moderate pressures(40,000 psi) should use CCI 400, Federal 200, Rem 6 1/2, or Win WSR. Such cases include 22 CCM, 22 Hornet and the 218 Bee. These primers can also used in handguns such as the 9mm., 357, etc. Other cases that use the small rifle primer can use the above primers only if moderate loads are used. Keep to the lower end of reloading recommendations.
Cases that utilize Small Rifle primers and operate at higher pressures (55,000 psi) should use CCI 450, CCI BR4, Fed 205 and Rem 7 1/2 etc."

"According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably."

 

[waterdog540]

You are using a small rifle primer with a cup thickness of less than .025, and possibly .019 in thickness, and a large rifle primer has a cup thickness of .027. Meaning as stated you need to change primers that have a thicker .025 thickness cup.

Below is a CCI 400 primer with a cup thickness of .020 that was fired in a AR15. If you have a firing pin on the long side and bump the case shoulder back too far the primer backs out of the primer pocket and the firing pin punches the center of the primer out. Meaning when the primer backs out after being hit the firing pin acts like a cookie cutter and pushes the center of the primer out.

So switch to thicker primers made for higher pressure cartridges and not thinner primers made for the lower pressure .22 Hornet. You are basically using a thinner pistol primer in a higher pressure rifle round.

Read the link below.

CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
http://www.sksboards.com/smf/index.php?topic=56422.0

"Cases that utilize small rifle primers and operate at moderate pressures(40,000 psi) should use CCI 400, Federal 200, Rem 6 1/2, or Win WSR. Such cases include 22 CCM, 22 Hornet and the 218 Bee. These primers can also used in handguns such as the 9mm., 357, etc. Other cases that use the small rifle primer can use the above primers only if moderate loads are used. Keep to the lower end of reloading recommendations.
Cases that utilize Small Rifle primers and operate at higher pressures (55,000 psi) should use CCI 450, CCI BR4, Fed 205 and Rem 7 1/2 etc."

"According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably."

You are using a small rifle primer with a cup thickness of less than .025, and possibly .019 in thickness, and a large rifle primer has a cup thickness of .027. Meaning as stated you need to change primers that have a thicker .025 thickness cup.

Below is a CCI 400 primer with a cup thickness of .020 that was fired in a AR15. If you have a firing pin on the long side and bump the case shoulder back too far the primer backs out of the primer pocket and the firing pin punches the center of the primer out. Meaning when the primer backs out after being hit the firing pin acts like a cookie cutter and pushes the center of the primer out.

So switch to thicker primers made for higher pressure cartridges and not thinner primers made for the lower pressure .22 Hornet. You are basically using a thinner pistol primer in a higher pressure rifle round.

Read the link below.

CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
http://www.sksboards.com/smf/index.php?topic=56422.0

"Cases that utilize small rifle primers and operate at moderate pressures(40,000 psi) should use CCI 400, Federal 200, Rem 6 1/2, or Win WSR. Such cases include 22 CCM, 22 Hornet and the 218 Bee. These primers can also used in handguns such as the 9mm., 357, etc. Other cases that use the small rifle primer can use the above primers only if moderate loads are used. Keep to the lower end of reloading recommendations.
Cases that utilize Small Rifle primers and operate at higher pressures (55,000 psi) should use CCI 450, CCI BR4, Fed 205 and Rem 7 1/2 etc."

"According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably."

I competed in 600 yard benchrest for a long time using a 6BR and a 6BRX and a Dasher. In those rifles I used CCI-450 primers exclusively. Never had a problem with a blanked primer. Have used 6.5x47 Lapua and a 6x47 lapua in a Remington 700 action with no problems using CCI-450 primers. Also use them in a 6mm Creedmoor . I have found these primers give a good extreme spread.
Just my experience.
Larry Isenhour

 

[Deleted member 102985]

I had this same issue with a custom 6x47 lapua. H4350 cci 450 mag primers. I got a new lot of powder loaded my old reliable charge first shot did the same thing out of 50 rounds 17 did this, backed my load down .3 grains issue went away. Shot over Chrono and velocity was back at my normal mode. I did have to pull my bolt apart and pull the little piece out of it every time. Just my 2cents worth. Good luck!

 

[19 Badger]

+1 about pulling out the piece of primer out of the bolt... Had a Cooper do this to me awhile back, everytime itdid the piece was inside my bolt. New firing spring cured mine.

 

[dsherk006]

I have seen this happen resently with a .26 nosler I was reloading for and there was too much headspace. The fireing pin actually punctured a hole in the primer on one cartridge. It ended up being a too much headspace issue.

 

[Alibiiv]

Just curious if you simply got a bad batch of primers. It happened to two primers, so....stuff happens sometimes. I recently went nuts changing out striker springs on all my rifles, turned out that I have a bad batch of Winchester large rifle magnum primers with hard anvils!! From your photos I'm not seeing any indications of high pressure loads whatsoever. At first I thought that perhaps your powder measure dropped a couple of heavy loads, but again no pressure signs as you wrote. You can try getting your rifle firing pin rebushed, however before I did that I'd keep shooting the components you have to see if it happens to more primers other then the two you have or buy a different brand of primers before repairing the rifle!! Could also call primer company with the lot numbers, could be a bad run??? There are made extraneous variables here, I suggest that you eliminate one of them at a time, primers then work on rifle. Remember this had happened with two primers out of how many?? For me I don't think you've fired enough ammunition using your present primers to find out if this is a fluke thing, or if you've got a primer issue at all. Like all other manufacturing products they're all subject to human error! I'd eliminate bad primers before doing anything else

 

[25WSM]

In 30 yrs of professional smithing ever instance of piercing has been solved by replacing firing pin spring or correcting head space. Mostly firing pin springs. Competitive shooters know how to set headspace. I personally have had 3 primers out of the 10s of thousands not fire. One was in upside down. One case didn't have powder. And one was wet from brass not being dried enough after cleaning. How many of you have done one of those. Please don't reply the thread will go viral. Shep

 

[lancetkenyon]

You are using a small rifle primer with a cup thickness of less than .025, and possibly .019 in thickness, and a large rifle primer has a cup thickness of .027. Meaning as stated you need to change primers that have a thicker .025 thickness cup.

Below is a CCI 400 primer with a cup thickness of .020 that was fired in a AR15. If you have a firing pin on the long side and bump the case shoulder back too far the primer backs out of the primer pocket and the firing pin punches the center of the primer out. Meaning when the primer backs out after being hit the firing pin acts like a cookie cutter and pushes the center of the primer out.

So switch to thicker primers made for higher pressure cartridges and not thinner primers made for the lower pressure .22 Hornet. You are basically using a thinner pistol primer in a higher pressure rifle round.

Read the link below.

CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
http://www.sksboards.com/smf/index.php?topic=56422.0

"Cases that utilize small rifle primers and operate at moderate pressures(40,000 psi) should use CCI 400, Federal 200, Rem 6 1/2, or Win WSR. Such cases include 22 CCM, 22 Hornet and the 218 Bee. These primers can also used in handguns such as the 9mm., 357, etc. Other cases that use the small rifle primer can use the above primers only if moderate loads are used. Keep to the lower end of reloading recommendations.
Cases that utilize Small Rifle primers and operate at higher pressures (55,000 psi) should use CCI 450, CCI BR4, Fed 205 and Rem 7 1/2 etc."

"According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably."

Great info....but....the OP said he is using Fed GMM primers, which would be the GM205M.

 

[19 Badger]

I run only CCI 450 primers in my 6.5 CM. Never had a problem so far...

 

[MASH]

Just curious if you simply got a bad batch of primers. It happened to two primers, so....stuff happens sometimes. I recently went nuts changing out striker springs on all my rifles, turned out that I have a bad batch of Winchester large rifle magnum primers with hard anvils!! From your photos I'm not seeing any indications of high pressure loads whatsoever. At first I thought that perhaps your powder measure dropped a couple of heavy loads, but again no pressure signs as you wrote. You can try getting your rifle firing pin rebushed, however before I did that I'd keep shooting the components you have to see if it happens to more primers other then the two you have or buy a different brand of primers before repairing the rifle!! Could also call primer company with the lot numbers, could be a bad run??? There are made extraneous variables here, I suggest that you eliminate one of them at a time, primers then work on rifle. Remember this had happened with two primers out of how many?? For me I don't think you've fired enough ammunition using your present primers to find out if this is a fluke thing, or if you've got a primer issue at all. Like all other manufacturing products they're all subject to human error! I'd eliminate bad primers before doing anything else

Currently two out of twenty that I have loaded. As for headspace since several people have mentioned it and its a valid point. I do use a headspace gauge and bump the shoulder back just under two thou and full length size.

 

[bigedp51]

Great info....but....the OP said he is using Fed GMM primers, which would be the GM205M.

And these Fed GMM primers he is using do not have a cup thickness of .025. I would first try a thicker cup primer and if that does not work then have the bolt face bushed.

If you Google the problem when switching to small rifle primer brass that pierced primers are a common issue with the thinner primer cups. Again my advice is to switch to any of the primers below with a cup thickness of .025 first and see if the problem stops.

Below are small rifle primer cases and the thickest primers are .025 and large rifle primers are .027 in cup thickness. And the thinner cups can cause more problems than the thicker .025 primers.