“Magnum” primers in .38 and 9mm

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Peakbagger46

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First primers I’ve seen for months and I thought they were standard ones (Remington 5 1/2). Apparently they are magnum primers.

What can I do to safety load these for .38 special and 9mm using Win 231 and Unique? I’ve got 1,000 of them to use up.
 
5 1/2 are not magnum. They do have a thicker cup to withstand higher pressures. They'll be fine for .38 or 9x19 with load data for standard primers because the cup thickness does not affect the pressure.
 
I just reworked a 9mm load to use a brick of mag pistol primers.

I ended up at my normal load, but I did notice that i wasn’t getting them seated as deep as I normally would? I had a few .001/ .002 proud. Maybe that’s a result of the thicker cup not being as willing to crush into the primer pocket.
 
5 1/2 are not magnum. They do have a thicker cup to withstand higher pressures. They'll be fine for .38 or 9x19 with load data for standard primers because the cup thickness does not affect the pressure.

Interesting, I am finding conflicting information on this.

At heart I’m a CCI man but these days one has to take what they can find!
 
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First primers I’ve seen for months and I thought they were standard ones (Remington 5 1/2). Apparently they are magnum primers.

What can I do to safety load these for .38 special and 9mm using Win 231 and Unique? I’ve got 1,000 of them to use up.

Load them the same as a REM 1-1/2 primer. You’re not going to blow up the gun.
I run REM 7-1/2 BR for 9mm major which are much hotter. The only risk is possible lite primer strikes.
 
I load .38 Special and .357 Mag with Mag primers and small rifle primers both because that is what I have. I've seen no ill effects. I use HP38, Bullseye, Unique and 2400. If I want to shoot I load what I've got. No problem at all, of course I can't measure pressure.
 
https://www.chuckhawks.com/primers.htm

A fairly decent primmer on primers.
The difference between “magnum” and “standard” primers has to do with one or more of four basic functional areas: brisance, pressure capacity, pressure generation/gas release, and burn duration. Brisance is how bright or hot the flame and compound ejecta is. Pressure capacity and release is how much pressure the primer cup can withstand without buckling or bursting and how much pressurized gas the priming compound produces. Sometimes higher pressure primers use thicker measures of a standard brass alloy but they can also use the same thickness of a stronger or more elastic alloy. Burn duration I’m hoping is self-explanatory.
Bottom line: anything stronger than the minimum required can be made to work safely in a modern firearm in good repair. Weaker is (can be) not good even in a good firearm.
 


Importantly, Remington never described them as Magnum. This is because they do not have more brisance, pressure generation, gas release or burn duration. Remington does describe their 9 1/2 M as "Magnum," evidencing that they did use this term to label primers, but not the 5 1/2. Brownells and Grafs may refer to 5 1/2's as "magnum" because they are suitable for magnum (high pressure) loads like 357 Magnum or 44 Magnum. What they will not do is ignite compressed loads of heavily-deterred spherical powders like H110, Lil'Gun, , HS-6, HS-7, 300-MP etc. It does not have the brisance or burn duration to ignite these powders well, whereas "Magnum" primers do. For the purposes of load development, 5 1/2 should be treated as standard primers because that's what they are. They will not create create additional pressure in loads compared to a standard primer, and can be used with standard primer load data. They will not perform well when a magnum primer is called for out of necessity, as with the powders mentioned above.
 
You can safely use the Remington 5 1/2 primers in your .38 Special and 9mm loads. Just drop down from your normal recipe and work back up like you should do whenever you change a component. Some handguns with a weaker hammer strike might not ignite those primers but usually only on handguns that have been worked on for a lighter trigger. Make up a batch of 10 or 15 and test them out. I'm fairly sure you will have no problems but they are perfectly safe to use. I'm also a CCI fan but as they say, any port in a storm. Buy them if you can and have fun at the range...
 
The 'safe' answer is to work up a completely new load starting a grain down, etc. In reality, unless you are already pushing a MAXIMUM load... as one already showing beginning pressure signs... switching to magnum primers is of no real significance. If you had taken a good average of your chrono velocities with the standard primers, you 'may' see a small increase with the magnum variants. If you're just loading mid level rounds, I wouldn't give it any thought. Good Luck
 
The 'safe' answer is to work up a completely new load starting a grain down, etc. In reality, unless you are already pushing a MAXIMUM load... as one already showing beginning pressure signs... switching to magnum primers is of no real significance. If you had taken a good average of your chrono velocities with the standard primers, you 'may' see a small increase with the magnum variants. If you're just loading mid level rounds, I wouldn't give it any thought. Good Luck

This is what I was told during the previous shortage. Start at 10% below maximum and work up to either maximum or where you're comfortable. Whichever comes first.
 
I load SRP in my Ruger .32 H&R loads because the firing pin protrudes a bit more than expected and it can pierce softer SPP primers on occasion. No issues after the switch. :thumbup:

I also loaded up 1,000 .38 and 500 .357 cases with them because I was running short of SPP. I haven’t loaded them yet, but when I do I will start lower and work up a load that shoots well like the manuals, and prudence, suggest. :)

Stay safe.
 
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