Using small pistol magnum primers

[Bmi48219]

Finding standard SPP's at a reasonable price isn't working out too well. I did find several thousand SPMag primers for $28.00 per K. If I have to I would use for loading 9 mm & 45 acp (have 500 Blazer brass w/spp pockets) under Unique powder.
I don't do hot loads, for example I load 45's at 5.3 or 5.4 gr Unique under a 230 copper plated RN.
Anyone out there substituting SPMP for SPP primers?

[FergusonTO35]

I have done it many times with good results, some powders actually work much better with magnum primers. Reduce your loads by a few tenths and you should be good. I would not use magnum primers in loads at the top or near the top of published data unless the data calls for them.

[44man]

SP and SP mags are not that far apart. I doubt you will see anything.

[Char-Gar]

The great Clinton gun, ammo and reloading components panic of 2016 is in full swing. Buy what you can and shoot them.

[Meatpuppet]

Ive used SPM primers in 10's of thousad 9mm 147gr loads in USPSA. My Standard Deviation is actually less with SPM primers than SP.

[JeffG]

All good to know. I noticed I bought a thousand small pistol magnum primers by accident. Been sitting on them for a while.

[ioon44]

I have been using SPM primers in .45 auto and 9 mm with great results, I just go to the starting load and work from there.

[tazman]

I haven't noticed any real difference between the standard and magnum small pistol primers. That said, I don't load maximum loads as a rule.
As others have said, I sometimes get better accuracy with the magnum primers but not always.

[Soundguy]

any time I change out a component, I just start a load test back at starting loads.

And yes, I have used mags in 38spl, and accidentally, non mags in 357 mag.

nothing bad happens when you work safely. :)

[B. Lumpkin]

I have used SPM and SR primers in place of standard small pistol primers. Just do a normal load work up using book data and you will be fine.

BTW- I ordered 5,000 standard small pistol primers from Midway this morning. They were $29.60 per thousand plus hazmat and shipping. Now is the wrong time to be looking for a deal. Now is the time to buy what you find as long as the price isn't triple from what it was yesterday, lol.

[FergusonTO35]

I'm going to start working up .38 Special and .45-70 with magnum primers. Past experience has shown me that magnum primers work better in cases with lots of empty space.

[jonp]

Ive done it in several guns and cant say ive noticed much. Im thinking of doing away with the spp and switching to smpp only to simplify things much as i have gone to Win Lpp for both loadings

[Johnch]

I have switched to SPM primers in the 9MM
As I have been using AA #7 and found the mag primer produced a lot lower SD in my loads

As I am using the starting load , I felt I didn't need to reduce my load any

John

[GONRA]

GONRA reminds ya'll that your SPM primers may be identical to the same mfg's Small Rifle primers.
Use 'em up accordingly.....

[tazman]

GONRA reminds ya'll that your SPM primers may be identical to the same mfg's Small Rifle primers.
Use 'em up accordingly.....

Are you referring to the cup thickness/toughness or to the amount of fire coming from the primer? Or possibly both?
Which brands are the same?

[Earlwb]

Are you referring to the cup thickness/toughness or to the amount of fire coming from the primer? Or possibly both?
Which brands are the same?

I had read about it sometime ago in this thread here, referencing post number 11.
http://smith-wessonforum.com/reloading/310555-small-rifle-primers-9mm.html

[Battis]

I recently started reloading for a S&W 1917 .45. I have some used PPU brass that takes Large Pistol Primers, and Federal brass that takes Small Primers. I can't find any load data for the cases that take the small pistol primers - just the large primers.
I used identical bullets (230 grs) and Bullseye powder (4.5 grs) in each cartridge.
The FPS using Large Pistol Primers averaged about 30 FPS faster than the Small Magnum Pistol Primers, and about 70 FPS faster than Small Pistol Primers.
So, the Small Primers were slower than the Small Magnum Primers, which were slower than the Large Primers.
There wasn't much difference from the Small Primers to the Small Magnum Primers. I don't know what the pressure differences were.

[Soundguy]

Just start at mins and load up, like any component change.

[str8wal]

I have used SPM and SR primers in place of standard small pistol primers.

Same here, couldn't find a small pistol primer of any kind around here after Newtown. Had to go to SR's for the 9mm and 38. Didn't see any difference in results.

[GONRA]

tazman - GONRA refers to decades ago,
eyeballing a Major US Ammo Mfg. 0.175 inch diameter primer assembly print.
"Usage Box" on the print said: Small Pistol Magnum / Small Rifle primers.
(One product, two usages.)

Some time ago Federal sold 0.175 inch diameter Boxer primers labeled for
"Small Pistol Magnum / Small Rifle". Maybe they (and others?) still do? ???

[tazman]

tazman - GONRA refers to decades ago,
eyeballing a Major US Ammo Mfg. 0.175 inch diameter primer assembly print.
"Usage Box" on the print said: Small Pistol Magnum / Small Rifle Rifle primers.
(One product, two usages.)

Some time ago Federal sold 0.175 inch diameter Boxer primers labeled for
"Small Pistol Magnum / Small Rifle". Maybe they (and others?) still do? ???



That is some very interesting data. Food for thought and speculation. Thanks for posting.

[FergusonTO35]

In 2013 I bought a bunch of Remington small pistol primers because they were all I could get ahold of. I noticed they were hotter than the Federal and W-W I had been using, also as many as 10% of them were too hard for any of my handguns to set off. I now reserve them for .357's in my Marlin 1894 and they work perfectly. I think R-P was sneaking small rifle primers in to get them out the door.