PRVI 54r - possible impending case failure....

[EBR Works]

I have about 500 PRVI 7.62x54r cases that have been reloaded now 5 times. Ever since the first resizing, the cases have had a line around the base of the case like this:



Checking with a steel dental pick internally did not reveal any evidence of a crack. I did some research and assumed that the line was being caused by the sizing die so I went ahead and continued to reload them with charges ranging from 43-48 grains of Varget with PRVI 150gr SPBT bullets.

Now at 5 reloadings, I decided to section one of the cases:



From this distance it doesn't look too bad. No visible impending separation or cracks.....but let's take a look closer look at much higher magnification:



Check out the very defined crack that is formed at the web!

Here's another closeup showing the crack traveling into the head (its slightly out of focus so I surrounded it with green):



....and to think my last load in these was at max of 48gr of Varget through my PSL!

Time for new 54r brass that is not PRVI!

[EBR Works]

More discussion and detail going on in my thread here:

http://www.thefiringline.com/forums/showthread.php?t=395373

[ocabj]

Based on the photos, I don't see anything wrong. As far as that super macro photo, I don't think that line is a crack. The external marks on the case are most likely a combination of the gun's chamber you're shooting it in and the resizing die.

I think you're reading too much into it. Your main concern is thinning and I don't see it.

But if you want new brass, Winchester 7.62x54R brass is available on a season run. Check with Grafs for those. There's also Lapua of which I actually did use the 7.62x54R brass.

[EBR Works]

There are cracks. Here's an augmented photo of the head:



..or should I not be concerned with these?

[cjskalka]

Based on the photos, I don't see anything wrong. As far as that super macro photo, I don't think that line is a crack. The external marks on the case are most likely a combination of the gun's chamber you're shooting it in and the resizing die.

I think you're reading too much into it. Your main concern is thinning and I don't see it.

But if you want new brass, Winchester 7.62x54R brass is available on a season run. Check with Grafs for those. There's also Lapua of which I actually did use the 7.62x54R brass.

I agree, whenever I've sectioned cases under the assumption that there's possible failure in a batch, the brass near the web has looked about half as thick as the brass around the body of the case and that's when I'd throw it out.

[Agustav]

My reload usually failed at the neck or shoulder area long before any signs of case separation occurs. I did noticed that Winchester or S&B brass seems to last longer then Prvi. However, the Prvi price offset the longivity issue.

[berg]

5 reloadings of a single case using a semi-auto rifle is a bad idea, IMO. Especially the way a PSL beats on the brass when it ejects.