Using CCI small pistol magnum primers for a 9mm?

M67 · Feb 10, 2012

I was looking around on the net and came across some interesting load data, that substituted SPM primers in loads that normally called for a SP standard primers in published load data.

The loads i saw, using the SPM primers, used a reduced powder charge from 10%-16%, to produce the same velocity as the SP standard primers.

I am curious, because i have a couple thousand CCI small pistol magnum primers, and nothing to load, using them. I use 2 types of powder for loading 9mm, W231 and unique.

Years ago during the reloading component shortage, i worked up a load for my 270 win rifle, using magnum rifle primers, with excellent results. I was wondering, if i could do the same thing for a 9mm pistol round.

Has anyone here used SP magnum primers, in place of, SP standard primers, and if so, what were your results?

Thank's

M67

deadshot2 · Feb 11, 2012

I don't know if I would do it on purpose but I did once by accident. I had a tray of SP Magnum primers mixed in with regular and loaded a whole bunch of 9mm rounds just like normal. I fired a couple rounds with the mag primers and didn't notice any issues in pressure or even loss of accuracy.

I've seen pictures of various primers when fired in a test fixture that shows the various flames developed. Some regular primers can be just as "Hot" as a magnum primer. The biggest difference in a standard or magnum primer is cup thickness. The magnum primer is designed to contain the higher pressures developed by magnum loads and keep them from blowing out when the firing pin strikes them. Interchanging of magnum and standard primers is common in cold climates when loads are developed with certain temperature fussy powders.

If you do elect to load with the magnum primers, just start lower and work up, but that's the proper way for any component change. I think you'll find that there won't be much difference although many claim a magnum primer will "open a group up". One possible side effect could be misfires if you have a weak or reduced hammer spring. Magnum primers do take a firm strike for reliable ignition.

CalTech · Feb 11, 2012

NO! Why take the risk in a high pressure cartridge? Is your gun and your health worth $75-80??

unklekippy · Feb 11, 2012

I personally do not care for magnum primers period. I have used regular primers in my .357's & .44 mags, using HP38 for target loads and H110 for hot loads. Never once have I wanted to use mag primers. I would only use mag primers in a 9mm if it were Mad Max time and it was all i had to stop my family from being raped and eaten. Even then, I'd make my wife shoot first, just to be sure. In all seriousness, please be safe if you do use them. Kip.

CrossHairs · Feb 11, 2012

I did some testing with Remington standard and magnum primers a while back for my 9mm loads. Now, I was loading light so this may be why(practice range rounds), but I saw no difference in speeds over the chrono at all. I would certainly caution that my own tests were with a different brand, with light loads, and my component set so your results may vary! I certainly would not use magnums for a hot load, that would be too risky. Like everything, approach with caution, be smart and if things look like they are getting hairy...carry scissors!

mookmanjdj · Feb 11, 2012

I just got done using 1000 SP Magnum primers in my 9mm loads. I think they are more reliable. I worked my way up to the load I liked and have had no problems at all. If you want to get rid of yours, let me know. 115 gr montana gold jhp with Win 231 5.0gr or 4.6gr bullseye. I was careful and worked my way up from a full gr lower on each.

BillM · Feb 12, 2012

Yes, you can do it. SPM primers have a slightly harder cup, and a slightly hotter flame.
I load 9mm minor and major power factor ammo, 40 S&W minor and major, all using
Winchester SPM primers. Over 30,000 total, no problems.

Pro's--less flattening with major loads. Reduction of extreme velocity spread due
to more consistent ignition on small powder charges.

Con's--harder cup, may be harder to set off with a full blown competition trigger
job.

Velocity---I see a consistent 10-15 FPS increase in velocity when switching to
SPM primers with no other changes.

Old506 · Feb 12, 2012

I have interchanged them many times and not just in 9mm. There is a minimal differance, Large or Small. I don't load to the ragged edge anyway and if I have mag primers, I will maybe lower the load by a tenth or so.

M67 · Feb 12, 2012

Thank you all, very much, for sharing your knowledge and experience.

no excuses · Feb 14, 2012

I think that it would be very dangerous for your health and safety, I will take them off youre hands lol. Justt treat it like any other change and start at the low end of the scale and slowly work youre loads back up to where you want them. I have a couple thousand WSPM primers that I wll be using in my glock in 40 S&W with clays powder.

dennisf · Feb 16, 2012

I have used only the spm (cci550) in my 9mm reloads and have not had one failure in either pistol. I shoot reloads only in my SR9 and Taurus 709 slim. I use 5.3 grns of Unique with the 115grn bullets.
My problem now is that I am setting up the Lee Turret press to expedite reloading of the 9mm only to find, in the fine print, that Unique does not dispense well thru the Lee auto disk charger set up. By changing disks, I am at a fairly consistent 5.3-5.4 grns over 5 charges checked. I stopped and went to the Lee website and found that little note at the bottom of the page. I don't really want to change powders and if so, I would like to use up the Unique that I have.
Any suggestions? I see bullseye noted in many loads. How does it meter?

SPU · Feb 16, 2012

dennisf said:
I have used only the spm (cci550) in my 9mm reloads and have not had one failure in either pistol. I shoot reloads only in my SR9 and Taurus 709 slim. I use 5.3 grns of Unique with the 115grn bullets.
My problem now is that I am setting up the Lee Turret press to expedite reloading of the 9mm only to find, in the fine print, that Unique does not dispense well thru the Lee auto disk charger set up. By changing disks, I am at a fairly consistent 5.3-5.4 grns over 5 charges checked. I stopped and went to the Lee website and found that little note at the bottom of the page. I don't really want to change powders and if so, I would like to use up the Unique that I have.
Any suggestions? I see bullseye noted in many loads. How does it meter?

I have the same press and Lee Pro powder drop. It dispenses Unique very well (YMMV). I find I have to almost fill the hopper and dump it back into the container a few times, then run 10 cases and I don't bother measuring them -- I just dump the powder back in the hopper. This is to get a good film on the disk and hopper and "innards" of everything. Then I measure five or six cases to be sure I'm getting the load I want (The disks are notorious for giving lighter loads than published). Then I get the load closest to what I want and go for it. Also, I note the amount of powder in the hopper; as the hopper runs down the charges tend to creep up. But you can use this to your advantage if the disk throws a slightly light or heavy charge -- change the amount of powder in the hopper.

This procedure has worked well enough I use it for all powders, including Unique. For production handgun runs I don't care if a load is off by a tenth from ideal weight personally.

I hope this might be helpful to you.

deadshot2 · Feb 17, 2012

Almost all powder measures benefit with the addition of a powder baffle, especially with "difficult powders". A simple piece of sheet metal (aluminum flashing material is easy to work with) bent in a tent shape, fitted to the interior of the powder measure, and with a couple of semi circles cut at the lower edges Usually 1/2-3/4" radius cutouts work best. The baffle keeps the powder from packing down on the metering orifice so it flows more uniform. The holes should be just big enough to let the powder flow easily without clumping or "bridging". Most factory powder measures don't have much more than a small rod shaped piece that acts like a baffle. the "square" Lee reservoirs are the most difficult to make a baffle for but patience pays off. Some loaders even use two baffles. One at the bottom of the reservoir and a second one half way up with the cutouts 90 degrees apart. It's all about making the powder freely flow which yields uniform charges.

mookmanjdj · Feb 17, 2012

I have used a lot of bullseye powder. I meter through an RCBS powder measure, don't have any experience with your setup, but I have always been able to hit within less than a 10nth with bullseye. I recently got some Win 231 because people on this site said it metered better. It does a little bit, but I think I came just as close with Bullseye.

dennisf · Feb 17, 2012

I built the baffle and installed it. I ran tests on 3 disks and did an average on 10. My load was looking for 5.3 and I averaged 5..2 after installing the baffle. thank you for the tip, it has made a difference already. I will make a small batch and test them Monday when I am at the range for range safety officer duty.

dennisf · Feb 21, 2012

I ran some test loads Monday at the range and both pistols did well with the 9mm done on the new setup using the baffle to control metering. I did not test them against my earlier run. I ran 5 rounds through each 9mm pistol for function and consistency, seemed OK. 10 down, 700 and something to go for this batch.

deadshot2 · Feb 22, 2012

dennisf said:
I built the baffle and installed it. I ran tests on 3 disks and did an average on 10. My load was looking for 5.3 and I averaged 5..2 after installing the baffle. thank you for the tip, it has made a difference already. I will make a small batch and test them Monday when I am at the range for range safety officer duty.

I'm not a big fan of the "Ten Average" method. It has major pitfalls as it only shows the average of ten loads dropped, not the consistency from one to the other.
Averages have their limits, for example. Stand with one foot in a pail of ice water and the other in a pail of boiling water. What do you mean you're uncomfortable? The average temperature is "Just Right"

Checking powder drops by averaging 10 won't spot the case of one drop being way high and another being way low by the same amount but it sure could be an issue in your firearm when the "high" load is high pressure.

I would rather take a sheet of paper, drop and weigh each load, record the value, then use an online calculator for Standard Deviation or Mean Absolute Deviation. The latter will be a more accurate view of what you'll be seeing in a string of reloads using your powder measure setup.

One last "tip", uniformity of powder drops is dependent on every stroke of the operating mechanism being the same. This is so the powder flows under the same conditions every time. If you have something around the bench that causes vibration, or you pause for any length of time, it's a good idea to drop and pour back a few loads in order to get rid of any powder that may have settled in a dense lump over the metering port. Establish a rhythm and stick with it. Erratic techniques yield erratic powder drops