No small mag pistol primers. Options?

S

Shadow9mm

New member
Ok, I know small pistol, small magnum pistol, and small rifle are interchange assuming you work up from start.

Has anyone tried small magnum rifle or just small rifle to replace small magnum pistol? Only got 50 spm left and I can't find more


Using lil gun in 357 mag with 158g xtps

357 mag runs the same pressures as 9mm, 35k psi. But I know lil gun generally need a magnum primer to get it to burn right.
 
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I've used small rifle in 9 recently. Gun is still in one piece and I've got all my fingers still. I think you nailed it when you said working smart. I wouldn't take my 9 major load and throw rifle primers in it.

Sent from my SM-G996U using Tapatalk
 
Shadow9mm said:
Ok, I know small pistol, small magnum pistol, and small rifle are interchange assuming you work up from start
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We know that about the CCI line due to online testing. I've not seen proof or evidence of it applying to other brands. Other than external dimensions, there is no SAAMI standard for primers nor for how much more gas a magnum primer makes, so I would not be sanguine about assuming what applies to CCI applies to other makers. In the CCI line, the Magnum Small Pistol and Small Rifle appear to be the same in some tests. I don't know about others. Seeing no performance difference between SP and SPM isn't always a given. There can be changes in velocity SD due to the larger gas volume from the SPM unseating the bullet before the powder burn gets well underway. It sometimes even lowers pressure and velocity because of that. Anyway, use modest loads to confirm your assumptions before proceeding to run full-tilt boogie.
 
Unclenick said:
In the CCI line, the Magnum Small Pistol and Small Rifle appear to be the same.
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I thought it was CCI - SPM was the same as CCI standard SR ?? I based this on an old thread from 2015 here but in that thread they were referencing a conversation with CCI in 2009 . Maybe they have changed there primers since then . I'm jumping in here because I do use CCI sr primers in some 357mag loads ( One with HS-6 and another with H-110 ) so It would be good to know for sure I understand this correctly thanks :)

FWIW , I'm only using SR primers in what should be SPM loads . I'd only try them in standard cartridges like 9mm if I had no other choice . YMMV


https://thefiringline.com/forums/archive/index.php?t-569295.html
from link said:
These are my notes from a conversation on June 14, 2009 with CCI's tech dept.

I called to discuss the technical differences between their primer types. I was put in touch with one of their tech reps who was very happy to discuss their primers. She mentioned that she had worked there for 38 yrs and was glad I wasn't calling to complain about the current primer shortage. I was asking about the cup thickness, formula differences, and formula amount differences between their #500 (SP), #550 (SPM), and #400 (SR). She had me hold a minute to get the detail specs up on her screen and this is what she said.

Cup thickness: The #500 has a thinner cup than either the #550 or #400, however, both the #550 and #400 have the same cup dimensions (including thickness) and material hardness (same brass).

Flash powder formula: All three sizes use the same formula for the flash powder.

Flash powder amount: The #500 has a slightly smaller amount (3 micrograms) than the #550 or #400 which both have the same amount.

I asked if the SR primers could be used as an acceptable substitute for the SPM primers. She compared the #550 and #400 and then replied that yes, they appeared to have the same specs, same dimensions, same cup thickness, same formula, and same amount of flash powder. She even noted that the SPM primers were slightly taller than the SP primers and were spec'd the same dimensions as the #400.
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Although I don't disagree completely, the "old" post was not old the first time I read it . That said thank you for clarifying that .

Since UN just talked with them last year . The most interesting part in all this is I now have to assume UN was correct when he said .

Unclenick said:
In the CCI line, the Magnum Small Pistol and Small Rifle appear to be the same.
Click to expand...

It just makes me wonder what the heck are the #400 made of if the small pistol and small rifle are the same . I know logic has no place in rocket science but that just seems odd to me , you'd "think" the small rifle primers would be different in some way to the spm
 
I've been using small rifle primers in pistol loads for many years even though many say not to do it. I've never noticed a difference except in the Makrov where I've noticed less dimpled primers from the slide slamming home with rifle primers.

Tony
 
Yeah I'll likely keep using the loads I worked up using the CCI small rifle primers . Key point being I worked the loads up from minimum charge to where I stopped which was below max but not by a lot but both loads are defiantly below max charge of the manuals max when using SPM primers .

I'll add I believe it was not best practices in 2009 to tell customers over the phone the primers were the same if they change them in the future "without" noting it somewhere or printing it on the package . This literally mean even what UN was told a year ago can be wrong now just one year later . what good is it to call up and ask questions if the answers can change yearly .
 
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MG, you are correct. I meant small pistol magnum and small rifle. My fingers jumped ahead. I've fixed the original post and quotes. This is why you have to be wary of online information. We all typo or pass brain gas at one time or another.

I did, as 74A95 says, speak to them again last year and got a totally different story from the first time I spoke to them. However, the first time I spoke to them, the lady on the phone took the time and trouble to use her computer to double-check that the cup, anvil, priming mix, and priming mix quantity all matched between the SR and SPM. In the newer conversation, no computer checking was done. The fellow on the phone just immediately proclaimed you should never interchange them and people doing that didn't know what they were doing and were "playing with dynamite". He was quite emphatic about it.

So I decided to test some of the newer production of these products for myself by firing wax bullets with them to get velocities and also doing before and after weight measurements on my analytical balance to see how they compared. Unfortunately, the primer shortage closed its doors about two days before I could get my hands on new production samples, so I had to put that experiment on the back-burner. But I wasn't the only person thinking about testing this. In January, this YouTube test by a loading business of a few rounds of 9 mm fired with both primers as well as standard pistol primer and taking pressure and velocity measurements was done. In his load, he could not identify any difference in performance between the three. Certainly, no "dynamite" was involved.

But in this other test with 357 Magnum and a slow powder, some difference was apparent, indicating the SR primer got the load about 10-11% higher in pressure (based on QuickLOAD modeling).

So now the question becomes, how much of the observed difference in the second case is due to the powder involved, the primer involved, lot variation in the primers, and so on? Is the larger primer in the 9mm just getting the bullet unseated and further forward in such a short time that the expansion difference accounts for leveling the pressure? Is it that you only see the difference in hard-to-ignite powders? Or is it just primer lots involved? I don't know. The second test, assuming no big lot variation, suggests these two primers are no longer exactly the same, but the two tests taken together suggest that whether or not you can discern the difference depends on the application.

As always, start low and work up.
 
Thanks Unclenick for the clarification and the links . I was actually quite concerned I had misremembered the differences . I'm more comfortable with how I've used small rifle primers in my 357mag loads .

I'm also interested in "if" the second guy using a rifle ( assume lever gun ) instead of a revolver would make a difference . I'd think you'd get more bleed off do to the cylinder gap using a revolver then a you might with a carbine . wondering if that would change anything and if so maybe the general result would be the same just lower avg velocities for both ???
 
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For a long time there were not any "Magnum" primers.

You will do just fine with regular primers in a .357 Magnum.
 
Quick update. I tested wichester small rifle primers with hodgdon lil gun for 357 mag. Slower burning ball powder. No issues igniting it.
 
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