ruptured primers

[javy]

Have found two primers with holes the size of a stick pin in the area of the radius of the primer. The primers are Winchester large rifle. The .260 load is 42.5 of h4350, 140gr. a max, Remington brass, 2nd firing.

No ejector marks, no hard bolt lift, primers are not overly flat but most of the radius is gone.

Upon decapping the two pieces of brass there is no black soot on the primer pocket wall. Primer pocket did not feel loose upon priming.

I now have a pitted bolt face. Pulled all bullets and punched out remaining primers.

Any body have any ideas what might be the cause?

Thanks, Javy.

 

[6.5 sender]

Re: ruptured primers

javy, I had the same problem with my 260 load. (140g. Amax 46.9g of 4831sc in a norma case and WLR primers) it was happening alot. I wasnt sure if it was the brass or my hot load, 2850fps, so I tryed cooling my powder charge way back, still happened. so I've switched to the federal gold match primmer and no more problems. long story short I think that the winchester primmers I had sucked.

 

[2Shots]

Re: ruptured primers

That load certainly isn't hot. Sure sounds like a couple of bad primers. I shoot 260 all the time, and hotter than that. I usually use BR primers. And everytime I have blown primers it was at the pin strike and the case usually showed pressure somewhere else.

 

[javy]

Re: ruptured primers

I want to agree with you guys, primer change might be the best bet.

Thanks, Javy.

 

[67rschev]

Re: ruptured primers

Had the same exact issue with WSR primers in a not too stout 600 yard 223 loading for service rifle . Switched back to Remington 7 1/2s , and no more issues . Seems as Winnie makes their primers a little thinner than others , there is a chart somewhere on the interweb of primer cup thickness .

 

[andymine]

Re: ruptured primers

winchester primers are weak,thin

 

[Hummer]

Re: ruptured primers

can you post pictures of these "holes". From the description I think I know what happened but I would like to see good close up pics if you can swing it. thanks

 

[javy]

Re: ruptured primers

Hummer, Don't have the ability to post pictures.

The holes were pretty round in shape and about the diameter of a straight pin. I punched the primer out of the cases and it appears that the hole originated from inside the primer cup, the inside of the primer pocket does not look any different than you would expect to see.

If you got any ideas, I would like to hear for my own knowledge.

Thanks, Javy.

 

[wnroscoe]

Re: ruptured primers

Javy, try the CCIBR2 primers in your 260. They typically have harder cups with a milder ignition. The milder ignition seems to give better/lower ES/SD. Just re-work your load as you might have to increase the powder charge by .2 to .4 to get the same velocity if your in a node.

I'm running 42.0 H4350 with 139 Scenars in my 260, BR2 primers as well.

 

[javy]

Re: ruptured primers

Wnroscoe, I was going to try some cci that I have or fed gold metal. Do'nt have ant BR2.

Thanks,Javy.

 

[kingtiger88]

Re: ruptured primers

I had the exact same problem ! I was able to see the exact same situation you describe . I sent Winchester an email explaining what happend and they immediatly responded . I had one primer that I had punched out and one still in the case (lapua brass ) .I mailed the blown primer and case with blown primer to them . They had me send all 5000 primers back to them and I exchanged it for brass . They sent me a letter expaining their regrets . Their lab technitions found that the primer cups failed ! If you have a bunch just get a hold of them and they will be glad to help you out . I went to CCI and federal primers and haven't had a problem since .

 

[javy]

Re: ruptured primers

Steve, The lot # I am having trouble with is DEL695G. Hope this helps.

Javy

 

[kingtiger88]

Re: ruptured primers

I don't have the lot number , sorry I was to pissed off about the bolt face .

 

[javy]

Re: ruptured primers

Kingtiger88, When I got ahold of Winchester today they wanted me to send in the rifle, 6 loaded rounds, lot #'s, spent primers, ect. I told them I was not sending the rifle or bolt in but would send in the other things they wanted and take pictures to send them.

Did they ever do anything about the bolt face? They did seemed more concerned than I thought they would.

Thanks,Javy

 

[Hummer]

Re: ruptured primers

Javy,
Is your striker nose perfectly hemispherical and having no sharp edges or tool marks? So you have small holes. Assuming there is no deformation of the striker nose I have to concur that you may have a lot of thin cups which happens to all manufacturers sooner or later.

Contact them with lot number after you confirm striker nose has no deformations. Then again it may have some now due to the leaking high pressure gases.

I was first picturing holes the size of the indent and that is from a different problem. They probably have a 800 number you can contact them with or write them a letter enclosing the primers.