Small pistol Magnum primers

[Brasso]

Finally got some SP primers but they are magnum. Should I download and if so how much? This is for 9mm Luger.
Thanx in advance.

Brasso

[JimB..]

Yes, and some.

Honestly, work up a load from scratch.

[Winger Ed.]

I've had to use some LPM for cast in .45ACP.
My loads are on the mild side anyway, but I dropped another half grain of Bullseye, and they do fine.

[poppy42]

I’ve used Small pistol magnum primers in loads for my 38 special, 9 x 19, and 9x18. I’ve noticed no appreciable differences, except maybe a little bit more of a muzzle flash from some of my smaller firearms. I have also done some cursory testing using small rifle primers in place of small pistol primers. I did drop A few tenths wow developing my loads . With all that being said these are the results that I had. All firearms are different and I have no idea if your results would be the same as mine especially seeing as I have no idea what powder and what loads you using. I am in no way suggesting that someone else do this without proper load development! do your own testing!
Be careful, Have fun, and good luck

[Brasso]

Thank you all. Start from scratch.

[tankgunner59]

I was going to suggest the same, drop 0.5 grain and test. If you so choose work your charge weight up from there. I don't own any large magnum rifles. One time that I was picking up some rifle primers I bought a box of what was labled large rifle standard primers, when I got home and looked the box was full of large rifle magnum primers. So I started asking the same question and this is the advice I received and it was spot on.

[dale2242]

I did a small test using large pistol and large pistol magnum with a light load of 700X and a 200 gr. SWC bullet in 45ACP.
I found I got 50 FPS more out of the magnum load with no difference in SD or ES.
Accuracy was the same.
I did the test in 2 guns.
A 1911 and Sig 220.
We are going to see a lot more cross using different primers in the near future.

[atr]

I have used them in both my .38 spl and .357Magnum and I have not seen an appreciable difference between them and the standard primers. I would agree that if you are loading to the maximum side of the powder charge it would be prudent to reduce that by 5% and work up from there.

[mfraser264]

Some striker fire handguns may struggle with the heavier magnum primer as they do not produce the force required to drive the firing. Something to keep in mind.

[Poygan]

I had loaded some 9mm using CCI mag primers and had about one third FTF on the first strike. Some would take two or three hits before they would fire.... This was in a Glock with no previous issues.

[454PB]

I posted some info here:


http://castboolits.gunloads.com/showthread.php?413373-Primer-comparison

[beshears]

When I switch my 9mm to mag primers my velocity jumps about 100 fps and extreme deviation doubles. 133 gr cast bullets and unique. Work up a new load.

[Kosh75287]

The 9x19mm is small enough in capacity that the extra "oomph" from the mag primers COULD push the projectile off the case mouth before adequately igniting the propellant. It's rare, but not unknown. The counter-measure to this is to use slightly more crimp.
Since you'll use more crimp, plus a magnum primer, both of which tend to increase pressures, it is VERY important to start at 10% below the max charge weight and work up gradually. This can be laborious, but it beats heck outta having to replace a firearm, or be fitted for some sort of prosthetic.