300BlkTalk

I pulled my micro 7 out recently to tinker with and remembered that last year I noticed my warm loads were producing primer pocket “looseness” after four or five cycles.

That was using new lake city 5.56 reformed brass.

I have 100 lapua brass but my regular load shot so bad in it that I put it away until I consumed the rest of the LC brass.

I’d love to hear what some of you fellows who like to experiment have found to be the longest lasting primer pockets?


Thanks.

For me Norma has probably been the longest lasting, then Lapua. Both have gone well past 10 firings of stout loads, Norma gets retired to subs or load work up after 15. These would be near or over max load for supers and generally low to mid 40k psi loads for subs.

The testing loads for Norma was a 155 grain bullet at 2230 fps using 296 using 10 cases in a 16” barrel. lost the first one at the 14th firing and still had 7 at 20, only one left at 22. At some point in there maybe after 7-8 firings I ran them all through a 223 full length die. The bases were hanging up, but I did not want to touch the shoulders.

Lapua started dropping off around 10-12.

LC never made it past 7-8. I think that was due more to the swaging of the crimps.

Absolute minimum sizing, using a Wilson full length bushing die. Setting the shoulder back .001”. Remington 7 1/2 primers.

Trued Model 7 action.

Thanks for those suggestions.

My LC brass is new so there are no crimps to deal with.

Regarding swaging I have switched to using a chamfer tool to remove them rather than using my swaging tool. I’ve found that lightly breaking the edge with a turn or two was all that was needed to allow new primers to be seated.

I use a Ballistic Tools go/no go primer pocket gauge to determine whether the case gets rejected. https://www.brownells.com/reloading/mea ... 00-015-613

It doesn't answer your question on max number of loads before the primer pockets loosen up, but the gauge will help you determine the end point easily.

I use the universal deprimer and toss when they come out easy.

I can say the Worst for me has been WCC, followed by FC followed by RP formed from 221 Fireball.

Blowout wrote: ↑Sat Jul 13, 2019 3:48 pm I use a Ballistic Tools go/no go primer pocket gauge to determine whether the case gets rejected.

thanks! that is just what I need. some of my brass is getting old and I have been having an occasional primer falling out. now I will be able to check them before loading.

If a primer goes in too easily, I take that case and stick it in a universal depriming die. If the primer comes out with little or no pressure, I chuck it and reuse the primer. If it "sort of" stays in OK, I mark it with a sharpie, load it and leave it in the grass when I shoot it. No way am I sticking a little doo-dad into every primer hole I load.....

popper wrote: ↑Mon Jul 15, 2019 11:36 pm I use the universal deprived and toss when they come out easy.

That’s my method. If it feels loose when I’m installing the primer, I pull out the recapping die and if I can punch it out by hand I toss the brass.

I appreciate the responses on the types of brass you’ve had troubles with. That’s the kind of discussion I was looking for.

If your ambitious you can try this to tighten the primer pockets. https://youtu.be/1ST25CUpqhY