Magnum primer oops

[mljdeckard]

I just bought some primers for 9mm reloads, and I get home, and....they are magnums. Are they safe to use?

 

[Promod1385]

Yep they should be safe to use assuming you aren't loading exceeding max published data.

As always start low and work up 10% at a time. Look for signs of pressure (flattened, bulged, or blown primers) and you should be gtg.

 

[mljdeckard]

Nah. For pistols, I just care that they go bang, I don't need them to be extra spicy.

 

[ArchAngelCD]

Agreed... Magnum primers only burn a little hotter and a little longer and do not cause atomic blasts. Like mentioned, as long as your load isn't bumping up against the max charge you are fine. As with any other change in components work up the new load.

 

[res7s]

The only primers I now order are magnum primers. That keeps it simple for me. As long as you do the load development like you're supposed to, when you change a component, you'll be fine.

 

[coalman]

Do not load them weak or they may leak and cause gas cutting. Load medium and up loads and you should be fine.

 

[chhodge69]

As long as you do the load development like you're supposed to, when you change a component, you'll be fine.

That's the key - they are not drop-in replacements for standard primers.

 

[swmp9jrm]

I just today chrono'd some .357 magnum reloads - was testing small pistol primers vs. small pistol magnum primers with the same powder load. I got about 11% higher velocity with the magnum primers. So I think as long as you stay away from hot loads you should be okay.

NOTE: this data was generated with Alliant 2400 powder in a light load - a faster burning powder might have a more pronounced increase in pressure and speed.

 

[Certaindeaf]

Closet door creaks open..
I only use small and large rifle for everything.

 

[ArchAngelCD]

I just today chrono'd some .357 magnum reloads - was testing small pistol primers vs. small pistol magnum primers with the same powder load. I got about 11% higher velocity with the magnum primers. So I think as long as you stay away from hot loads you should be okay.

What powder are you using? It does matter...

 

[Hondo 60]

Ya, I'd be concerned about powder as well.

A very fast burning powder with a magnum primer could shoot the pressure up considerably

 

[swmp9jrm]

Ya, I'd be concerned about powder as well.

A very fast burning powder with a magnum primer could shoot the pressure up considerably

Point taken on the powder type - I was using Alliant 2400. The load was a relatively light load (16.0 gr with a 125 gr HP bullet) and I just wanted to see what kind of difference the magnum primer makes.

 

[fallout mike]

There are many threads on this. With whatever load you are using, when using magnum primers in non magnum calibers, use 10% less powder. I read this from a reputable source and have had great success with it. I have been meaning to test this myself with the chrono but just keep forgetting. But looks like its dead on going by swmp9jrm. Ill still test some of my 9mm's and .40's as well whenever I remember while im actually at the deer camp shooting.

 

[Clark]

I have found that at high pressure load work ups that changes 9mm brass, that switching to magnum small pistol primers is the equivalent of 0.7 gr more AA#5.

That may not be applicable to wimpy published 9mm loads.

 

[jcwit]

Closet door creaks open..
I only use small and large rifle for everything.

Large rifle for both pistol and rifle cases? Not a good thing. Large pistol and large rifle primers are two different sizes. Trouble on the horizon.

 

[gamestalker]

So long as you work your loads up using them, you'll be just fine. However, the primer cups are a bit thicker than standard primers cups, so depending on your firearm and how it handles them may be a factor as well. I would doubt that will be an issue, but I have heard of problems with light striking weapons.

GS

 

[jjjitters]

I've got a pistol caliber that requires rifle primers because of piercing issues(not due to being overloaded). As long as the gun has a strong enough firing pin spring,rifle primers work fine,same as using magnum primers.Just do the workup.I have several loads that I have tested between standard and magnum,most have been more accurate with the mags.Powder type I think makes a difference.

 

[OrangePwrx9]

I got into trouble using magnum primers on some near-max .357 Blue Dot loads. Got a lot of pierced primers. That powder definitely doesn't want or need magnum primers.

Blue Dot works well in my 9mm and is becoming a favorite, but I'm careful to use standard primers with it.