Using Magnum Primers in a Non-Magnum Round

[MarkInNashville]

So I found magnum small pistol primers for use in 9mm. I was told I should reduce the amount of powder I use by 10%. Anyone know anything about this and is it the right thing to do or should I not use them?

[npgunner]

I've heard the same from a LGS I go to for reloading advice. I didn't purchase them though because I wanted to do some research on it, but I never did. I know this isn't very helpful other than to say "I've heard of that also, but had the same question."

[frankmako]

yes you can use mag primers in 9mm and 40 s&w.  i have and will again when i can not find any standard primers.  at first i did the 10% lower charge with the mag primers.  then i ran some loads with my normal charge weight.  ran the mag primers with my normal charge weight across my chronograph and the mag primers gave me about 60 pfs more.  i don't run any of my reload hot.  i load them in the mid range so the family can have more fun at the range.  what i have found using mag primers in non mag load is that i don't get much unburned powder now.  so mag primers in place of standard primers will give you a small bump in fps and a better powder burn.

[Jamie Jackson]

I've had no issues at all with mag primers in my 9mm reloads.

 

During the last "phase of madness" I purchased 5000 Wolf small pistol mag primers. I actually prefer them to standard Wolf SP primers now.

 

I initially dropped the load by 10%...checked for overpressure signs, and worked back up to about 5% less than my initial load.

 

Unless you're running near max loads I wouldn't be concerned.

[RED333]

Good info, thanks guys.

[CatsEye]

I used SPM primers some during the last shortage. My 9mm loads were within 10 fps on loads tested. It is always good practice to reduce and work up but there is virtually no difference.

[PackinMama]

Does this go for small rifle magnum primers as well?

[Lumber_Jack]

David sold me some Large magnum pistol primers for loading .41 Magnum and told me I could use them in .45 ACP no problem

[Dolomite_supafly]

Does this go for small rifle magnum primers as well?

 

Yeah, you can use small rifle magnum in 223/5.56. There are some small rifle primers that you cannot use for 5.56 like Remington 6.5's. But other than that most small rifle magnum should work with 5.56. I use or have used CCI 400, CCI 41, Remington 7.5, Wolf SRM and Tula SRM for 223 without any issues.

 

I also use small rifle magnum primer for my 9mm loads and my samll primer 45 ACP loads. As long as you work up accordingly you will not have any problems.

 

Dolomite

[Mike.357]

I only reload .357 and .38 special now, but I use mag primers.  Of course I am shooting them out of a magnum revolver.  I did not change any recipe.  The mag primers worked great.

[PoofNoEyeBrows]

I also use the 10% reduction formula when swapping reg. for mag. primers and have not had a problem.

[RED333]

I only reload .357 and .38 special now, but I use mag primers.  Of course I am shooting them out of a magnum revolver.  I did not change any recipe.  The mag primers worked great.

:wave: I would nevr have guessed by your handle.

[Guest tnpaul]

I only use mag. primers with powders that call for them.

[gregintenn]

Winchester large pistol primer are marked "standard and magnum". I would be surprised if there is much difference in other brands.

[Guest 6.8 AR]

You beat me to it Greg. I kept looking at Winchester primer boxes until we ran out, and that kept sticking out to me. Scratched my head on it. :D

[Dolomite_supafly]

There are differences between magnum and standard. Not only in the power but also in the cup thickness.

Dolomite

[Dolomite_supafly]

From this website:
http://www.accurateshooter.com/technical-articles/primers-and-pressure-analysis/

Dolomite Edited February 11, 2013 by Dolomite_supafly

[Dolomite_supafly]

And before someone points out those are rifle dimensions, I know. There are similar differences between magnum and standard pistol primers.

Dolomite

[Dave Shooter]

During the last primer shortage I loaded some small rifle magnum primers in 9mm.  None of my striker fired handguns would reliably set them off; hammer fired guns fared better.  Your mileage of course may vary, just wanted to say you may want to test a few before loading a bunch.  I wound up giving that ammo to a friend with a SMG, where they worked fine.

[MarkInNashville]

During the last primer shortage I loaded some small rifle magnum primers in 9mm.  None of my striker fired handguns would reliably set them off; hammer fired guns fared better.  Your mileage of course may vary, just wanted to say you may want to test a few before loading a bunch.  I wound up giving that ammo to a friend with a SMG, where they worked fine.

Excellent heads up, thank you! I believe that I bought http://www.midwayusa.com/product/2900117598/winchester-small-magnum-pistol-primers-1-1-2m but I will go home and check now, to verify!

 

I got them at the Reloaders Bench in Mount Juliet (close to Nashville) and they know what I reload. Don't think they would steer me wrong but, as former President Ronald Reagan said "Trust but verify!"