primer cratering and boltface pitted

[DrMike]

I always smile at the speed some people get out of the rums.... I have a 30 - 378 which has more case capacity but I can never get near those speeds without seeing pressure..... the difference appears to be the way Norma brass is made for the 30-378 vs 300 Rum brass. All I can say is that quick load seems pretty well coordinated with my 30 - 378. Some of the" safe" loads I see people running in the 300 rum get near a 80,000 PSI forecast ....ouch!
Then again we have the federal Factory loadings for the WSM that often can never hold a primer pocket after the first firing!

Kraky1, we went through a period when the Lazzeroni cartridges were very popular. It seemed as if everyone was having a Lazzeroni built or was buying a Sako chambered in that cartridge. Many were shocked when they discovered that the cartridges, which were marketed at an exorbitant price ($125 for a box of twenty at the time), lasted for three loadings at most, and many were finished after one loading. To say that the pressures generated were excessive, is to fail to do justice to the English language.

 

[kraky1]

I remember those and I think the sako 30-378 I have is the exact same gun they re chambered into lazzeroni.
I wonder who they got to make those cases for them....and.... if I remember right the bullets they used had some kind of Miracle coating on them? Which is not to say some of the Coatings might not work I still remember the old xlc Barnes.... seems like the coating works sometimes and other times not so well. Really...for me.... having quick load and a chronograph during all my reloading development is very big for me....... not the end-all but very big.

 

[truck driver]

I do believe I also post in another thread where I had a Federal M215 primer burn out the exactly where this one did. I'm not sure if I had cleaned up the primer pocket or not but would suggest you uniform the the primer pocket so the primers are seated deeper.

 

[TackDriver284]

Would it be a good idea to send the rifle and bolt to my gunsmith to get that bolt face fixed and smoothed out? I just don't like the looks of the bolt face and this is a new barrel build. Geez. All my brass was checked for pressure signs, seems OK to me except for those weird rings around the primers. Here is a picture.

 

[longrangehunter]

I can tell you that funky wave appearance on the primer cup is from imprinting due to the surface of your bolt.

If it were me, I'd buy a new bolt w/a M16 extractor like a PTG, or something like it. In the long run you'll be happy you did, and get a better extractor.

 

[truck driver]

I can tell you that funky wave appearance on the primer cup is from imprinting due to the surface of your bolt.

If it were me, I'd buy a new bolt w/a M16 extractor like a PTG, or something like it. In the long run you'll be happy you did, and get a better extractor.

+1 What he said.

 

[TackDriver284]

I can tell you that funky wave appearance on the primer cup is from imprinting due to the surface of your bolt.

If it were me, I'd buy a new bolt w/a M16 extractor like a PTG, or something like it. In the long run you'll be happy you did, and get a better extractor.

I agree too. What if I send the rifle back to the gunsmith that built my rifle and let him fix it. I, also, hear a few guys tell me to send the rifle / bolt to Gre Tan to fix the bolt. Anyone hear of him or his work?

 

[Dwh7271]

I agree with the bolt comments.
Check into having a bushing for the firing pin too perhaps?

 

[IdahoCTD]

A PTG bolt is good but would have to be fitted. Gre-Tan should be able to bush the firing pin and fix the bad spots while doing it. It shouldn't effect the headspace more than .001.

 

[truck driver]

Just for the record I had this happen with federal primers also in my 7mmRem.
Here's pictures of the primer. I had to modify the pictures to down load since they were over size so I hope you can see the hole in them.
They're all the same primer and if you look at nine O-clock in the one where I'm holding the primer you can see the pin hole and the of the one on the table it's at 5 O-clock.
The load was a light load of RL22. I've had this batch of Federal magnum primers for a while and this was the first time one has popped but I did go to CCI after that and have had no problems.
( click on pictures and they will enlarge )

 

[garyw1911]

First of all , I do not own a Magnum caliber rifle. However , I did have lot of Fed210 primers that was not compatible with my lot of R-P brass in a new Savage Stryker pistol in 7mm08 ( Bolt action ) . My brass case head and bolt face was plasma etched similar to yours , but not quite as deep . Part of the cure is switch primers to CCI as your last post mentions . In my case , I had a treasured lot of pre-1999 Win primers ( Nickel plated) . I went to a great deal of trouble to find the root cause of my problem , which may be different than yours ( but it looks the same ) .
About 50% of my lot of Fed210's were oversize for my lot of R-P brass . If I tried to seat an oversize primer , I could see a slight mushroom on the primer at the radius , under 5x magnification. That made a weak spot in the primer that pierced at the cup radius on firing . I was able to use the same lot of primers in WW and FC cases with zero problems. As a final test , I fired the same etched case with the same powder charge and a Nickel plated Win primer with no further problems . ( The load was verified in other brass first , and the primer pocket was inspected for an etch track in the sidewall) . Hope this helps.

 

[TackDriver284]

gary, If I could remember,,,I used the RCBS primer tool, and I recall having very tight fits with the FED215M primers, do you think I may have deformed one of them that caused the primer leak? Some would say I was over pressure, some did not.
One of the signs on the primers that was fired had the circular indentations etched on them, upon looking at the boltface, there was a little cratering around the firing pin hole. That could have weakened the primer structure upon firing which pitted the boltface. Sadly my gunsmith did not take the cratering into account when he built my rifle. After sending the gun back, he repaired the boltface and I got my rifle back last week. Shot the gun a few days ago, seems good, and primer face are smooth compared to the way it was.

First of all , I do not own a Magnum caliber rifle. However , I did have lot of Fed210 primers that was not compatible with my lot of R-P brass in a new Savage Stryker pistol in 7mm08 ( Bolt action ) . My brass case head and bolt face was plasma etched similar to yours , but not quite as deep . Part of the cure is switch primers to CCI as your last post mentions . In my case , I had a treasured lot of pre-1999 Win primers ( Nickel plated) . I went to a great deal of trouble to find the root cause of my problem , which may be different than yours ( but it looks the same ) .
About 50% of my lot of Fed210's were oversize for my lot of R-P brass . If I tried to seat an oversize primer , I could see a slight mushroom on the primer at the radius , under 5x magnification. That made a weak spot in the primer that pierced at the cup radius on firing . I was able to use the same lot of primers in WW and FC cases with zero problems. As a final test , I fired the same etched case with the same powder charge and a Nickel plated Win primer with no further problems . ( The load was verified in other brass first , and the primer pocket was inspected for an etch track in the sidewall) . Hope this helps.

 

[longrangehunter]

Well that's good your gunsmith took care of you. Switching primers and check your speed over a chronograph should help steer you in the right direction.