Possible Primer Problem?

[mete]

Yes , when in doubt, throw them out ! Even new primers can cause the problem ! Had a friend who had that problem and took a wooden rod with him when hunting. I got mad and told him to toss the primers .He took my advice .At about the same time I was getting very hot loads about every tenth round even though my load was less than max. I tossed the primers - end of problem !!

 

[Katsumi Liquer]

Just a follow-up to my original post.

The S&B SR primers which failed to ignite my .454 Casull loads with H110/W296 have no problem lighting off my standard .223 Rem loads using H335 and BL-C(2) powder. I've shot about 300 rounds with the SR primer through my ARs with no misfires yet. And for that I'm happy, as the primers are serving their intended purpose.

I also experimented with using the same S&B SR primers in my .357 Magnum loads using H110/W296 and experienced no problems with ignition. Surprisingly, the reduced power hammer spring in my Ruger GP100 was able ignite the primers with 100% reliability. Thus far, I've only fired about 50 of these rounds with the SR primer, but I consider it a bonus.

I have since also purchased several bricks of S&B SP primers and found them to be just as reliable as the other "mainstream" SP primers in the various pistol calibers that I reload, although they do take just a wee bit more effort to seat into the primer pocket. I did end up crushing a few while trying to seat them into S&B brass (9mm and .40 S&W) which is known to have tight primer pockets. That begs the question: assuming S&B use their own primers in their factory cartridges, how do they avoid crushing the primers during the seating stage???

 

[Unclenick]

They just make the primer pockets big enough. The tolerance range is significant for primers and primer pockets. Download this SAAMI document and scroll down to page 26 (page 35 as Acrobat Reader counts the pages) for dimensioned drawings of all three centerfire cartridges and primer pockets. You'll see about 0.0020" range for the primers and 0.0015" range for the pocket diameters. That's more than enough to make quite a difference to a press fit.

At least a couple of guys have mentioned that in rifle cartridges that tend to shoot their primer pockets loose over time, when domestic primers are too easly to slip in or won't stay in, they just switch to ones made in Russian or somewhere else in the old Soviet controlled countries.