Reloading Question

[Gunner4h1r3]

OK, just got back from a deployment and did a quick inventory of what primers I have left. Found out I have a bunch of Small Pistol Magnum, but not a whole lot fo Small Pistol (which I use mainly for 9mm and .380). Is it possible to use the SPM primers in lieu of the SP primers?

 

[ranger335v]

Yes, but if i did it I'd back off on the normal charges a half grain or so.

 

[Gunner4h1r3]

ok. so if I was running 4.7 grains of HP38 with a 115 grain 9mm FMJ, back it down to 4.0-4.2?

 

[loadedround]

According to my Hodgdon Manual, 5.1 gr is the max load for HP38/115 gr/fmc bullet. Your load is quite a bit below that and I would first try a few rounds with the magnum primers paying close attention to the usual pressure signs. I would venture a guess that you will see little or no difference except to increase your velocity about 50 fps or so. Good shooting!

 

[Taildragger-J3]

This is interesting. I HEARD (never believe everything you hear) that using a Mag primer shouldn't affect the load. It just gave a more consistent "light off" to the round than standard primers. I've been using Mag primers because that's what I was able to get. Thanks for the update.

 

[rcmodel]

I think we covered this twice in the last week:
Heres this about that.

http://www.thehighroad.org/showthread.php?t=474899

http://www.thehighroad.org/showthread.php?t=474128&highlight=magnum+primers

rc

 

[ranger335v]

".. a Mag primer shouldn't affect the load. It just gave a more consistent "light off" to the round than standard primers."

Yeah, "Use a hotter primer for better igniton!", that's a poplular misconception. If it were true we would all be using nothing BUI mag primers.

 

[rcmodel]

Exactly right.

Most non-magnum pistol calibers give worse Standard Deviation with magnum primers then with standard primers.

Too much of a good thing, so to speak.

Use them if you must during the current primer shortage.
But it's always best to use the right primer for the job if you have a choice in the matter.

rc

 

[ArchAngelCD]

Welcome home Gunner4h1r3, thank you for your service...

Like said above, with the charge you are using I doubt any change in charge will be necessary. I've also found using a Magnum primer with W231 to be less efficient but hey, you use what you have when times are tough...