Had a misfire today with the old .358 M99F. This is the first one that I can recall in 50 years of reloading. So far it seems to be a accumulation of tolerances that did not allow the firing pin to strike the primer hard enough.

It was caused by using new brass that was not fireformed and then FL sized just enough in an old chamber that must be at the maximum headspace.

Then the primers were CCI 200's that only measure .1256" high but the primer that did not fire after being decapped measures only .1202"! I cannot tell if this primer was compressed to this even smaller dimension by the firing pin or not.

Other primers that I have are higher. WLR's are .1289" high and Remington 9 1/2's are about .128" also. CCI BR primers only measure .125X also.

The primer pockets in these new WW .358 Win cases were bottomed with a Whitetail primer pocket uniformer. It cuts just the depth to about .130"

In conclusion I am snake bit on CCI primers. And I was really doing well with them group wise.

How deep were the primer strikes on the rounds that fired, compared to the depth of the strike on the round that didn't fire?

Any possibility of fouling or other build up on the firing pin shoulder?

I'm really liking the Rem 9 1/2's these days...

Dan

The depth on the first try was less than a normal indent. I tried it twice. It pushed the primer deeper into the pocket as that primer is .005" shorter than the others which are .004" less than WW's or Rems. When I pulled the bullet the other cause was apparant as the case was bright and shiney inside. A new case.

I have a thousand of 9 1/2's' that split on the outside corner and leak. I should soak them in oil and scrap them.

I think I need to pick a new primer.

Don, be cautious with the oil. Several guys have experimented recently, and oil DOES NOT reliably kill today's primers, even after days of soaking.

I did some tests soaking seated primers with water, and it appeared to have NO EFFECT on the primer. Just be careful. FWIW, Dutch.

Dutch,

I read that oil did kill primers and I tested one and it worked on that one. I have at least a thousand 9 1/2's that split and then the leak cuts into the bolt face!

Remington gave me permission to send them back but it's such a hassle for only a few bucks worth of primers.

Thanks for the heads up. Our transfer station sends the trash to be burned!

Everything is a problem.