Small Pistol Magnum Primers - Substitute for Small Pistol Standard??

[hoodat]

So I find myself real heavy in the mag primer department, just because for awhile that's what was available. I'd like to start burning them up, and was wondering if anyone's been doing the same.

Handgun loads will be primarily 38 spec, and 9 luger. My most common powders are HP-38 Auto Comp, HS-6, Green Dot, Red Dot, Bullseye, mostly fast burning stuff.

I've read that the main difference is the cup thickness, and not power (brisance). jd

[JimB..]

Many, many discussions on this. Use them, but as usual work up loads esp if you shoot near the top of the suggested powder charge.

[Bmi48219]

So I find myself real heavy in the mag primer department, just because for awhile that's what ……jd

I am in similar circumstances and in my experience the biggest issue is whether the firing pin will strike with enough force to ignite the primer. In this regard I’ve had no problems with CCI and Winchester SPMs. I do have a slew of East European SPMs that don’t play well with striker fired pistols. Fortunately I only load for a few striker pistols.
I can’t speak to variances in power and agree the cup thickness, to me, is the big difference.

JimB.. makes a good point.

[Tatume]

Neither ignition nor pressure have every given me cause for concern when using small pistol magnum primers. Starting loads are what I usually use, and I use magnum and non-magnum small pistol primers interchangeably.

[NSB]

That’s all I’ve been using for years now. I find no difference in ignition or performance. FWIW, Winchester now lists their large pistol primers as “magnum or regular”. Using “book” powder charges for your revolver loads, I doubt you’ll see any difference.

[Baltimoreed]

I traded all my small pistol primers for large pistol primers last year so now I'm using small rifle primers for38 and 45acp. I found that my lightened mainspring Vaqueros [for cas] were having problems igniting the thicker rifle primers so I had to replace my mainsprings. Other than that they work fine. Use the same load as before but I don’t run hot loads in any of my guns. Btw, CCI primers.

[hoodat]

Thanks fellas for your response. You all seem to agree with what I'd read, (and suspected) myself.. Of course any company manual will tell you to NEVER change any of the listed components.

I've got one handgun (Beretta FS92) that I have installed a lighter hammer spring in. I'm gonna load a dozen or so to try for function before I crank out a couple hundred for it.

I've got both Federal SP mags, and CCI 550's that I'd like to use up. AND -- I've been told that CCI 550's and CCI 400's are the same.
jd

[Ford SD]

Thanks fellas for your response. You all seem to agree with what I'd read, (and suspected) myself.. Of course any company manual will tell you to NEVER change any of the listed components.

I've got one handgun (Beretta FS92) that I have installed a lighter hammer spring in. I'm gonna load a dozen or so to try for function before I crank out a couple hundred for it.

I've got both Federal SP mags, and CCI 550's that I'd like to use up. AND -- I've been told that CCI 550's and CCI 400's are the same.
jd

From the web


NOTE 1: According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably.

Note I will not use the CCI 400 in 223 /556 unless it is a cast load = lower pressure

I have had flatter primers with CCI and Cast in the 300AAC and will now only use the Mag SR Primers in those

[racepres]

I never had problems shooting my cast 221 Fireball cast loads with Magnum small pistol, just cause I gots em!! I feel the tougher cup is a Plus!!!
Not that you asked about that...but, for me it was a Better Use, than in 38SPL!!!

[Bowdrie]

Note I will not use the CCI 400 in 223 /556 unless it is a cast load = lower pressure

Nor will I, the stock heavy firing pin in many ARs has a lot of inertia, and because it is free floating, has been known to cause slam-fires.
A Titanium firing pin will prevent that, but yes, the CCI 400s are not recommended for use in ARs,
Here's more info on primers;
https://www.sksboards.com/smf/?topic=56422.0

[stubshaft]

I have no problem using SPM primers in mostly everything except the 32 ACP.

[racepres]

I have no problem using SPM primers in mostly everything except the 32 ACP.

I suspect due to Light Strikes?? But, I'm Guessing
Oh...Almost forgot...If you wouldn't use CCI 400, do Not try Remington 6-1/2's... Easy to Blow the Cup...BTDT
Edit; Apologies for the Drift...but, in these times of Shortages, I will stand by Not Using Remington 6-1/2's except for Handgun loads...and I do Not mean something like 327, nor 357 Max...
They gave Great accuracy in 38Spl wadcutter loadings..shortage! Remember

[hoodat]

Well, upon further research and testing, it looks like Small Pistol Magnum primers is the most practical type to buy if available.-- at least CCI's. They can serve as small for magnum, small rifle standard, and all small pistols providing the hammer/striker is strong enough. Whether or not to use them in an AR platform is up to your own judgement, and plenty of folks are.

I got out yesterday and tested the Federal SP Mags in my Beretta, and things were fine. Of course Federals have a reputation for soft cups anyway. I'll still have to check the CCI's before I'll load a bunch in this gun. I'd hate to load a quantity and find that they're unreliable. jd

[Electrod47]

CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
Based on an article by John Barsness - GUNS magazine pg 26 May 2009. [JB, formerly of
Handloader is one of the most qualified gunwriters when it comes to primers and reloading in
general]
Information from the Speer #14, Hornady #7, Nosler#6, and Lyman #49 reloading manuals, Alliant
and Accurate Arms data.
Additional Information from James Calhoon - "Primers and Pressure" Varmint Hunter Magazine,
October, 1995
Hopefully this explains a bit more about, not only primers in general, but specific characteristics
that can aid a reloader in choosing the optimum sparkplug. Pertinent information will be added to
this section when more information becomes available.
BRISANCE
Primers come in different strengths, technically known as “brisance,” a word defined as “the
shattering effect of a high explosive.”
Primer brisance mostly depends on the length of the flame that leaps out of the flash-hole after the
firing pin whacks the primer cup. This flame can also be manipulated to last a little longer, by
adding tiny particles of other flammable material to the priming compound. These differences
really can effect not just accuracy but pressure.
For instance, in a very small rifle cartridge such as the .22 Hornet, a “hotter” primer might start to
dislodge the bullet before the powder really gets going. Instead of a relatively gentle, slowly
accelerating push, the bullet gets cruelly hit hard. This is why some Hornet fans use small pistol
primers, with much milder brisance than small rifle primers.
Really huge rifle cases such as the biggest Weatherbys, Remington Ultra Mags, and older British
African cartridges require a lot of very slow-burning powder to operate at all. Slower-burning
powders are normally more difficult to ignite, and a bigger flame of longer duration helps,
especially in cooler weather. The first “magnum” primer, the Federal 215 was designed for this
very purpose. Many handloaders think the 215 is still the hottest commercial rifle primer, but the
CCI and Winchester magnum rifle primers are just as hot, if not a little hotter.
Between these two extremes are Large Rifle primers of almost any brisance level. Remington and
CCI primers tend to be the mildest “standard” primers and Winchesters the hottest (the reason
that Winchester never had a magnum rifle LR primer until recently), with Federals somewhere
between. Deciding which to use depends not only on the size of the case but the powder.
How fast a powder burns depends not only on granule size (bigger granules have more relative
surface area) but on exterior coatings. Extruded powders, such as relatively small-grained 4895 or
large-grained H-4831 depend mostly on granule size to control burning rate. Ball powders don’t
vary much in granule size, so depend mostly on relatively flame-resistant exterior coatings to
control burning rate. By definition, these coatings make ball powders harder to ignite.
For example, in the 30-06, IMR 4895 is very easy to ignite, one reason it’s often suggested for
reduced loads down to 2/3 of a case’s capacity. We’ll probably get the very best accuracy from a
mild primer such as the CCI 200.
To make the 30-06 zip however, we might try Ramshot Big Game. The Ramshot ball powders burn
cleaner than most ball powders, but they also require more flame. Winchester Large Rifle primers
are the hottest “standard” rifle primer and often perform very well with Ramshot powders, but if
they don’t definitely try a magnum primer. This can often result in smaller groups.
Something else to remember is that competition rifle shooters often favor mild primers i.e. primers
that produce just enough heat to properly ignite the powder. They feel that as primer brisance gets
higher, it also gets less repeatable from primer to primer. Another train of thought is that the
powder is ignited a tad more gently. When this happens, the front slope of the pressure curve is
less steep. Which means the bullet is pushed a tad more gently into the rifling which tends to
deform it less. Whatever the scientific reason, competitive rifle shooters seem to feel that the
milder primers give both better velocity uniformity and accuracy.
The same principles also applies to handgun cases. You might find that magnum primers aren’t
good for milder loads, especially with cast bullets for some reason or another (Elmer Keith claimed
that the hot flame tended to slightly melt the base of the bullet - no way of knowing if that is true.)
Whatever the case, often using a standard pistol primer can reduce group size with milder or cast
loads.
On the other hand, magnum primers are almost always recommended for magnum loads,
especially if hard-to-ignite ball powders like W296, or its H-110 twin, are used. In fact, magnum
pistol primers were developed for the large case revolver magnums like the .357, .41, and .44
Magnums. They seldom are needed for standard autoloader rounds or standards like the .38
Special.
Some powder manufacturers recommend standard pistol primers with certain of their powders
even in magnum pistol loads. Alliant 2400 is one where the use of magnum primers is strongly
discouraged, and another is Accurate Arms, which recommends standard pistol primers with their
handgun powders, including #9, unless “they provide better accuracy in your firearm.”

[elmacgyver0]

cast bullets for some reason or another (Elmer Keith claimed
that the hot flame tended to slightly melt the base of the bullet - no way of knowing if that is true.)
Easy enough to see if you use a suppressor.
Even the mildest loads will vaporize a small quantity of lead that will condense on the baffles of the suppressor, the majority on the side away from the muzzle of the gun.
Powder coating greatly reduces the vaporization of the lead.
This is a fact, not my guess, easy enough to check, just get a suppressor, one you can disassemble.

[Bowdrie]

One thing to keep in mind about Elmers remarks on primers is that for much of his life he was dealing with primers that were of the old corrosive variety, they were primarily fulminate of mercury, (real hot,) and he had far fewer powders available to him than we do now.
The military ammo, whatever powder they used for a particular round, had to have primers that MUST under any circumstances fire the charge, even if the ammo was below zero temperature.
And if the rifle or machine gun round doesn't fire when the enemy is at your foxhole bad things happen.
Powders do burn different, but that is primarily due to coatings and shape.
All nitrocellulose burns at pretty much the same rate, coatings and grain shape are the big controls for burn rate.
When spherical powders ignite the exposed surface area is constantly decreasing as the charge is consumed.
When tubular powders ignite the outside surface area is decreasing but the inside surface area is increasing.
As such, given the same coating, the ball powders show a different curve of pressure rise than the tubular powders.

[Larry Gibson]

This topic comes up much more often these days of primer shortages. Here's an extensive test I ran some time ago.

9mm; SP and SR primers

The last few months there have been several threads regards the use of SP magnum and/or SR primers in the 9mm cartridge. I had conducted a test of SP and SR primers in the 357 Magnum and posted the results [https://castboolits.gunloads.com/sho...he-357-Magnum]. In that cartridge with Unique powder there was enough evidence demonstrating the SP Magnum and SR primers could raise the psi enough to warrant caution in doing so.

However, does that correspond to the 9mm cartridge which was the subject of the question. Some definitely thought the substitution should not be made. Others were adamant that using a SP Magnum or SR primer in the 9mm with a given load posed no problem. A video showing a limited test by a commercial reloader demonstrated no different in pressure or velocity. Others stated they found little variance in chronographed velocity as proof there was no difference in psi. I proposed caution be used should it be necessary to substitute SP Magnum or SR primers in the 9mm with a given load.

I have just completed 3 additional more fairly comprehensive pressure/velocity tests of 3 different powders [Bullseye, VV 3N37 and HS-6] in the 9mm cartridge.

A commercial loader request I test the 9mm cartridge with CCI’s 500, 550 SP primers using 6.1 gr VV 3N37 under a 115 gr FMJ bullet. He supplied the powder and the bullets.

To provide a comparative reference I also loaded test rounds with the same primers using 4.9 gr Alliant Bullseye and the 115 FMJ bullets [listed as a maximum] and also included the CCI 400 SR primer and the CCI 450 SR magnum primers. Testing was done in a 10” Contender barrel with a strain gauge affixed and connected to the Oehler M43 PBL. The SAAMI MAP for the 9mm cartridge is 35,000 psi.
The test of the comparative reference load [4.9 gr Bullseye] proved quite interesting. The test results briefly;
Primer, velocity average, psi average:

CCI 500 SP primers; 1331 fps, 35,000

CCI 550 SP Magnum primers; 1341 fps, 35,000 psi

CCI 400 SR primers; 1338 fps, 35,000 psi

CCI 450 SR Magnum primers; 1330 fps, 35,000 psi

Note the test to test variation in velocity is well within the test to test expected variation of the same load. What was really surprising was the pressure for each and every shot, regardless of the primer, was exactly the same…..right at the SAAMI MAP for the 9mm cartridge. Looking at the internals [time/pressure curves, area under the curve and rise to pressure] a slight difference could be noted. The CCI 550 SP Magnum and the CCI 450 SR Magnum primers gave slightly more uniform internals than either the standard SP or SR primers!

I then conducted the second test using the provide VV 3N37 powder. The test results;

CCI 500 SP primers; 1236 fps, 32,300 psi

CCI 550 SP Magnum primers; 1253, 34,500 psi

Note, with the use of VV 3N37 powder, we have a distinct difference in results with this test than with the previous test with Bullseye. The internal ballistic measurements again indicated the CCI 550 primer gave slightly more uniform ballistics. The CCI 550 Magnum primer also gave a noted increase in velocity [20 fps increase vs the 10 fps difference with Bullseye] and an increase in pressure of 2,200 psi.

In a previous thread it was Lloyd Smale (If memory serves me correct as I couldn’t find the thread with “search”] that was adamant with is 9mm load of HS-6 in didn’t matter with his mid-level HS-6 load what primer was used as all were “safe”. He also rather adamantly suggested I test HS-6 and find out. So I did.

Lyman lists 6.2 gr HS-6 as their max load under a 120 gr 356402 bullet. I didn’t have the Lyman bullet but have the Lee 120 gr TC bullet [123 gr cast of COWW + 2% tin], so I chose to use that load. Even though Lyman lists that load as “max” the CUP measurement of 29,300 indicates it is not a “max” load as the CUP SAAMI MAP is 33,000. I have on hand 13 different SP and SR primers [7 SP primers and 6 SR primers] so I loaded up a test with each of them.

Again, the test load was 6.2 gr of Hodgdon HS-6 under the 123 gr Lee TC cast bullets.

The test results by primer used;

Small Pistol primers;

Federal 100 SP primer; 1255 fps, 34,800 psi

CCI 500 SP primer; 1227 fps, 34,700 psi

Magtech 1 ½ SP primer; 1243 fps, 35,000 psi

Winchester WSP SP primer; 1247 fps, 35,000 psi

CCI 550 SP Magnum primer; 1210 fps, 34,400 psi

Federal 200 SP Magnum primer; 1214 fps, 34,700 psi

Winchester WSPM SP Magnum primer; 1253 fps, 35,000 psi

Small Rifle primers;

Remington 7 ½ SR Primer; 1229 fps, 34,700 psi

Winchester WSR SR primer; 1220 fps, 34,800 psi

CCI 400 SR primer; 1237 fps, 34,800

Federal 200 SR primer; 1253 fps, 34,800 psi

CCI 450 SR Magnum primer; 1228 fps, 34,700 psi

Federal 205 SR Magnum primer; 1222 fps, 34,500 psi

Appears Lloyd was certainly correct, there really isn’t much difference regardless of the primer used. Also. interesting to note that 3 of the SP primers pushed the psi right to the SAAMI MAP whereas none of the SR primers did. That is one of the things I really like about this game and that is I’m always learning. In this case I’ve not only learned from actual testing but also through research to find the facts about primers. Turns out, once again, I and most others were misled over the years into thinking SP magnum primers and SR primers would increase the psi with a given load because they were “hotter” or had more explosive power. Turns out that isn’t true. The primers only hold so much compound and the energy produced by that amount of compound is finite. Thus, SP and SR primers essentially hold the same amount pf priming compound which essentially increases the same amount. SPM and SR/SRM primers apparently do not increase the psi per se by themselves. The difference is in the priming compounds and how they “burn”. The SPM and SR/SRM primers compound gives a longer flame burn is all.

So, if that is the case then why did two of the tests [the 357 Magnum with Unique and the 9mm with VV 3N37 powders] show a marked increase in psi with the SPM and/or the SR/SRM primers? The answer to that appears, at least so far, to lie in the nature of the powder used. My guess at this time is any real potential increase in pressure with the use of a SPM or SR/SRM primer will be dependent on what kind of powder is used [single or double based], the kind of deterrent [controls the burn rate] that is used and probably any flash retardant used. Thus, as it turns out, all who participated in the past thread were essentially correct some of the time and potentially wrong at other times. This is evidenced as I’ve not found any conclusive evidence one way or the other to definitively say substituting a SPM or SR/SRM primer in a 9mm load is safe because, like many things we’ve found in reloading, it depends.

I will still, as of this writing, stand by my original suggestion; if one has to substitute a SPM or SR/SRM primer in the 9mm cartridge for a load proven safe with a SP primer developed load then use caution.

[hoodat]

Thanks Larry. I really appreciate your write-up and your skill and equipment that you use.

Those results pretty much bear out the previous info I'd seen (supposedly by an employee of CCI) stating that CCI 400 and 550 primers are identical, with the same amount of primer compound, as is the CCI 500, although with thinner cup metal.

I don't know what to think about the result you got with the VV powder. jd

[Rapier]

Goes back to reloading 101, change any part of the load, then you always reduce the load and then work back up, to accuracy or the performance level desired. No short cuts or assumptions, ever, do it. Time and time again folks want to take short cuts.
My loading data log books notes, all include the make and type of the primer used.
Pretty much every computer has the capability to create reloading log pages or notes and those pages can be transfered from device to device and carried with you. Little excuse for not keeping range notes.

[Froogal]

I guess I am not nearly as scientific as some, but I use either SP or SPM primers interchangeably with NO noticeable difference in performance. I load the same powder and the same bullet and use whatever primer is available. I prefer to use SP, but if SPM primers are all I can find, that is what I use.