Magnum small pistol primer in 9mm

[Montman]

I screwed up. Bought magnum small pistol primers by mistake and loaded 200 9mm rounds with them before I caught the mistake.
100 loaded with 7 grains Accurate Arms #7 powder and 115 grain bullet.
100 loaded with 6.7 grains Accurate Arms #7 powder and 124 grain bullet.
Will the magnum primer over power these rounds?
Should I just trash these?

 

[ReloaderFred]

You should be ok with those loads and Magnum Small Pistol Primers, since your powder charges are near the start loads for those two bullet weights, according the Lyman 49th Edition Reloading Manual.

Hope this helps.

Fred

 

[ArchAngelCD]

This question comes up often. If you do a search you will see it.

Some loaders actually use SRP in their 9mm ammo. I would not but it's done. If I were you I would worry more about the fact you loaded up 200 rounds before you realized you were using primers you didn't want to use. You opened and used two sleeves of 100 before it was caught.

 

[kingmt]

I usually use srp so I don't have to keep as many different things on hand. I've used magnum also. It's all the same in the paper down range.

I'll also suggest reading the package before loading. If you make the same mistake with bullets out powder it'll be much worse.

 

[DownInTheDark]

I've used magnum primers by accident for 9mm loads. They were close to the max but they didn't blow up the gun. Hope that helps.

 

[Clark]

15 years ago in a work up with 9mm 115 gr and AA#5, switching to magnum primers changed the brass case pressure sign threshold the equivalent of 0.7 gr of AA#5. The change in velocity is less. My experiment was at extraordinarily high pressure and with a faster powder. Those two variables should cancel to some extent. That would make using a magnum primer at normal pressure the approximate equivalent of 0,7 gr more AA#7.

 

[Sunray]

You might have slightly increased pressures, but not enough to matter. Magnum primers don't over power anything. They just burn a bit hotter for a bit longer than standard primers.
Like Ron says, you're at Accurate's start loads for 115 and 124 grain cast/plated bullets anyway. Nothing to worry about.

 

[dave333]

I came into a great deal on several thousand small magnum primers a while back and haven't seen any significant difference in my loads, including some much hotter loads using AA #7 out of my open gun. Just shoot them, no problem.

By the way, the load you are using with #7 is probably going to leave a bit of unburned powder in your gun. It may still be an accurate load and I'm sure it will function fine but it will be a bit dirty.

 

[FROGO207]

Yep you should be OK. The only concern I would have would be harder cups and a chance a weak strike might not fire the round. Some have noted this when using small rifle primers (after workup) in certain handguns. I have used magnum and SR with my revolvers after load workups with no problems.