Primers, Does it Matter?

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Looking through my reloading manuals, they all tend to suggest a certain type and wondered if it really matters which brand you use as long as they are for that kind of load and firearm?

Like the Sierra manual says to use Rem 7 1/2 primers for my AR 223 loads and I have Rem 6 1/2, Wolf 223, and CCI 41 primers.

 

[jonbearman]

You can substitute primers as long as they are all the small rifle primer or large that you need.If it calls for a std small rifle you can try any brand to see if your rifle likes them.Just dont use pistol for rifle thats all.I would use the tulas if you have them or the 41's.

 

[37Lincoln1]

Looking through my reloading manuals, they all tend to suggest a certain type and wondered if it really matters which brand you use as long as they are for that kind of load and firearm?

Like the Sierra manual says to use Rem 7 1/2 primers for my AR 223 loads and I have Rem 6 1/2, Wolf 223, and CCI 41 primers.

Do not use the Rem 6 1/2 primers in your AR. The 41's and the Wolf should be fine.

 

[Thumb]

Looking through my reloading manuals, they all tend to suggest a certain type and wondered if it really matters which brand you use as long as they are for that kind of load and firearm?

Like the Sierra manual says to use Rem 7 1/2 primers for my AR 223 loads and I have Rem 6 1/2, Wolf 223, and CCI 41 primers.

Do not use the Rem 6 1/2 primers in your AR. The 41's and the Wolf should be fine.

OK but can you tell me why I should not use the 6 1/2 primers, they are small rifle primers?

 

[GSPV]

The harder primer cup of the various SR Magnum primers helps prevent slam fires and primer piercing.

 

[finnaddict]

Do not use the Rem 6 1/2 primers in your AR. The 41's and the Wolf should be fine.
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OK but can you tell me why I should not use the 6 1/2 primers, they are small rifle primers?
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Use of 6 1/2 primers in .223/5.56 loads can result in pierced primers/gas leakage with the resulting gas leakage eating pits in the face of your bolt. Enough pits in the face of the bolt and the bolt can be ruined. The 6 1/2 primers are for lower pressure rounds like 30 Carbine. I don't know about the priming compound, but the primers themselves can't handle as much pressure as 7 1/2 primers.

 

[finnaddict]

http://forum.accurateshooter.com/index.php?topic=3824809.0

 

[Thumb]

OK, I'll have to see if I can trade them with somebody that has 7 1/2's or possibly sell them off.

I'm new to reloading only having reloaded a few hundred pistols rounds and just starting to load some 223. I knew there was standard and magnum primers but never thought a primer made for small rifles had restrictions.

Thanks for the info.

 

[lrgoodger]

Read the warning on the box for the 6 1/2. They are for very low power cartridges and will cause primer piercing in .223 or larger.

 

[Thumb]

Yes, I had to get a magnifying glass to read it. I don't have any other rifles so I'll see what I can do to trade or sell them.

 

[Tzed250]

Be advised that the CCI #41 primers are a small rifle magnum primer and that loads should be adjusted accordingly.

 

[BoydAllen]

YEARS ago, before the introduction of the .222 Remington only made one small rifle primer, the 6 1/2, and the only common rifle caliber that took small rifle primers was the .22 hornet. When they were doing the development work for the .222 they found that the higher pressures that it was loaded to gave problems with the 6 1/2s due to its cup being too thin, so they introduced the 71/2 that has a thicker cup, and solved the problem. That is why you have been rightly advised to not use 6 1/2s in your application. The pressure is higher than they were designed for. The other consideration in selecting primers is pressure. With everything else in a load held constant, different primers will produce different pressures and velocities. For this reason, any time that a component in a load is changed, the powder charge should be reduced and a new workup done. This is one place that a chronograph can be useful, since there is a correlation between velocity and pressure, when making comparisons with the same rifle.

 

[Thumb]

OK, I've come up with a full-proof plan, I'll use the primers that are suggested in the manuals. ;D

 

[brxbrad]

As you can see in these articles......Primers do Matter
http://riflemansjournal.blogspot.com/2009/06/primers-large-rifle-primer-study.html
http://riflemansjournal.blogspot.com/2009/06/primers-small-rifle-primer-study.html

Maybe this will help...

 

[markm87]

You can get away with using 6-1/2s with medium loads. You can also just run those primers in pistol loads if you're running hot AR ammo.

But to the original questions... primers can be substituted relatively safely, but there can be HUGE differences in accuracy.

We did a controlled .223 SMK load experiment with only the primers being the variable. It was AMAZING the difference it made in the set load.

WOLF ended up on top. BR-4 for whatever reason wasn't even MOA... just didn't play well in that formula.

 

[DRNewcomb]

You can get away with using 6-1/2s with medium loads. You can also just run those primers in pistol loads if you're running hot AR ammo.

Back in the days when I was stocking up on components for "just in case", I did some tests and found that small rifle primers would function properly in all my pistols that use small primers. I read someplace that the major difference between small rifle and small pistol primers was the strength of the metal in the cup; the pistol primers being "softer" to be more sensitive to a lighter firing pin strike. Because of that, I didn't buy any small pistol primers for my "just in case" stash.

 

[markm87]

Yep... I've even run Small Rifle Magnums in my 9mm loads... about a 1% failure to fire rate though with the thicker cup.

 

[Thumb]

My plan on the most part was to just use the reloads in the AR more for just plinking and fun so they would be light loads. I am going to load up some 5.56 loads for 100 yard plus shooting so I would be using different primers anyways for those.

I do have some pistols and maybe use them for my LCP .380. My other ones are a Glock 9mm, Kahr 40 S&W and a Ruger Security 6 Revlover 38/357 which I don't know would be good for.

 

[Thumb]

Was able to pick up 1000 CCI BR-4 primers today so I'm all set to go.

Thanks for all the great info and insight. Next time I'll read all the very small fine print.