Primers

[Pete]

Having used the Russian KVB-223 primers over the last year, and finding them a tad soft, I measured the cup thickness, together with the magnum version, BR4, and Rem7.5's.
I potted them in some resin and ground them down to make a crude microsection......see attached pic.
Measurements were made with eyepiece graticule calibrated with stage micrometer. (1.0mm into 100divisions), Nikon Labophot 2 microscope.

For what it's worth, here are the results:


A= Rem7.5 Thickness of cup where the firing pin hits it: 0.027"
B= KVB-223M : 0.024"
C= BR4 : 0.027"
D= KVB-223 : 0.019"

I wasn't too sure about the 223M's, but after measuring them, I tried them with a stiffish load (155 Scenar at 3075fps) in 308 Palma cases, and they were fine.

I also measured these: (Same technique ).

KVB-223 Std, (the copper coloured type Lot 1-11 that were available initially) : 0.020"
Federal 205 SR : 0.022"
Sellier & Bellot SP : 0.015"

Anyone who's used both the original copper plated std KVB's and the latest std brass coloured version will know that the later type are less robust, although the thickness is almost identical.....The copper plated version is probably a tad harder.

However, the KVB-223 Magnum's are in a different league altogether.............I've now found them to be very consistent, and hard enough to be a very good substitute for BR4's at almost 1/3rd of the price. Now my std. primer, and at £21-50/1000, a definite no-brainer.......get 'em from HPS-TR.

Pete

For some reason the layout has changed between the "preview" and my typed out version

[Daryll]

It does amaze me how things that should be made to "a standard", can differ so much... especially with primers.

I recently started reloading .308, using GGG brass, and my nearest gun-shop only had CCi primers. (I prefer Remington primers for my pistol calibre reloading, simple because they're readily available and I've had never had any problems with them).
I bought a couple of hundred of the CCi, and used them fine in the GGG brass after reaming the crimp out, and used my Lee hand primer tool.
I then managed to get a box of Remington primers (9 1/2), and started to prime some cases... or tried...

The Remington just would not go in using a manual tool, so I started using the priming arm on my press. That did seat some of the primers, but some were being flattened by the force required to seat them.

The cases were primer reamed at the same time, and to the same degree, as those that worked fine with the CCI primers, but I ended up running the reamer twice more through those cases before they'd consistently accept the Remington primers. I'm sure if I tried CCI primers in those cases now they'd be a loose fit.

So... like many things in life, "a standard" sometimes isn't...

[Maggot]

I have gone over to the Magtech SR 7.5s, they seem to be very good.

[WelshShooter]

Excellent post Pete, thanks for taking the time to do this!

In large rifle primers I've used Fiocchi, Federal and CCI. I've found that the Fiocchi primers require more effort to seat into an 8mm Mauser cause compared with Federal and CCI.

With regards to thickness/hardness, I found standard rifle primers (CCI) were getting pierced in my 6.5x47 Lapua with very modest loads. I tried the magnum rifle primers (same brand, CCI) and they do not get pierced even with some stout loads. I bet that the thickness of magnum cups are higher than standard primers. I thought the only difference between these primers were the intensity of ignition required to burn slow magnum powders.