Is Cimarron CIP or SAAMI?

[justindad]

Is a Cimarron .357 made in Europe according to CIP pressure requirements? This gorgeous thing is on Midway.
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I have no need for a single shot .357. I have a Uberti .45, but not with a bird’s head grip. The .45 ain’t this purdy.

[Larry Gibson]

Theyhave to be proof fired in Europe with C.I.P. standards. SAAMI lists 14,000 psi (Piezo/transducer) and C.I.P. lists 16,000 psi. In reality, not really a lot of difference there between them. Stick with standard manual level loads for Colt revolvers. That level of loads will be a handful in that revolver.

[justindad]

I’m looking at a .357 Mag Cimarron.

[shooting on a shoestring]

Yep it’s purdy!

My experience with bird’s head grips on a 327 Ruger Single 7 and the 357 Henry is they look way better than they perform. I find it hard to get exactly the same grasp, same position on the bird’s head frame and my groups show it. It’s also harder to keep the pistol from slipping my grasp (rolling up) under recoil. That also adds to bigger groups.

If you want to play with a bird’s head, I think you’ll have better luck with 357 than 45 Colt bc the gun will be a bit heavier. That’ll help a little in keeping the grip in your grasp.

I made a pair of stocks (grips) for my bird’s head Single 7 that are fuller and more squared across the rear. That helped a lot. I can hang on to it much better now and hit with it.

[justindad]

Nice job on those grips!
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That bump on the top of the grip might help with a consistent grip, but it might also hammer the thumb knuckle during recoil.

[Larry Gibson]

I’m looking at a .357 Mag Cimarron.

Same requirement to be proof fired to C.I.P. specifications.

CIP measures pressure at the case mouth (or thereabouts) and SAAMI take their measurement in the middle of the case. This the ONLY reason there is a difference.

[kerplode]

Cimarron is really just an importer. Most all of their stuff is made in Italy by either Pietta or Uberti. As such, they're proofed to CIP standards.

[35 Whelen]

Cimarron (Uberti or Pietta) are built and proofed to CIP standards. Here are C.I.P.'s pressure standard for the .357-





We have to convert the pressures from bar to PSI, so the .357 maximum average pressure as per C.I.P. is 3000 bar or 43,511 psi (bar x 14.5037738 = psi) (SAAMI pressure standards for the .357 Magnum is 35,000 psi) and those revolvers are proofed at about 56,500 psi. And some people think the Italian revolvers can't "take it"!

If you're interested in C.I.P.'s pressure standards, here's the link- C.I.P. Pressure Standards

35W

[Larry Gibson]

Cimarron (Uberti or Pietta) are built and proofed to CIP standards. Here are C.I.P.'s pressure standard for the .357-





We have to convert the pressures from bar to PSI, so the .357 maximum average pressure as per C.I.P. is 3000 bar or 43,511 psi (bar x 14.5037738 = psi) (SAAMI pressure standards for the .357 Magnum is 35,000 psi) and those revolvers are proofed at about 56,500 psi. And some people think the Italian revolvers can't "take it"!

If you're interested in C.I.P.'s pressure standards, here's the link- C.I.P. Pressure Standards

35W

Posting again so we may understand the difference is simply where the pressure is measured at: CIP measures pressure at the case mouth (or thereabouts) and SAAMI take their measurement in the middle of the case. This the ONLY reason there is a difference.

[justindad]

Posting again so we may understand the difference is simply where the pressure is measured at: CIP measures pressure at the case mouth (or thereabouts) and SAAMI take their measurement in the middle of the case. This the ONLY reason there is a difference.

Are you saying that: if I were to buy a 43ksi CIP proof round and a 35ksi SAAMI proof round for .357 Mag - the two rounds would essentially be the same?

[M-Tecs]

The SAAMI proof round pressure for a 357 is 47,000 PSI minimum and 50,500 maximum. SAAMI, CIP and NATO EPVAT all measure at different points so all three will have different pressure readings for the same cartridge. Same for transducer PSI verse CUP.

https://saami.org/wp-content/uploads...12-13-2022.pdf page 168

https://www.gunsandammo.com/editoria...testing/458750

https://www.theballisticassistant.co...sure-pressure/

https://firearmshistory.blogspot.com...g-chamber.html

[35 Whelen]

Posting again so we may understand the difference is simply where the pressure is measured at: CIP measures pressure at the case mouth (or thereabouts) and SAAMI take their measurement in the middle of the case. This the ONLY reason there is a difference.

So that means that a .357 load as tested by SAAMI that produces 36K psi, would produce ~43.5K psi if it were tested using CIP's method? And vice versa?

35W

[Larry Gibson]

So that means that a .357 load as tested by SAAMI that produces 36K psi, would produce ~43.5K psi if it were tested using CIP's method? And vice versa?

35W

Probably.

However, a pressure taken in one test barrel may not (more than likely won't) be the same as the pressure measurement of the same ammunition in another test barrel using wither SAAMI or C.I.P. methods. That is why "reference" ammunition is used to obtain a correction factor to validate the difference between test barrels. Some refer to this also as "calibration".

[justindad]

As an fyi, and because I’m a big dork - ksi is a legitimate abbreviation for 1,000 psi. It’s in mechanical engineering textbooks.
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Thanks for pointing out the differences in the measurement systems. Don’t extrapolate SAAMI data up into CIP pressure ranges and pay attention when using Quick Load. I believe VV powders use CIP system, so I won’t use their data for an American made .357.

[35 Whelen]

Probably.

However, a pressure taken in one test barrel may not (more than likely won't) be the same as the pressure measurement of the same ammunition in another test barrel using wither SAAMI or C.I.P. methods. That is why "reference" ammunition is used to obtain a correction factor to validate the difference between test barrels. Some refer to this also as "calibration".

Understood.

So we circle back to the original question regarding Cimarron, or really, Italian revolvers and the pressure requirements for them. That would be C.I.P. with their pressure specifications for the .357 being ~43,500 psi and proof at 1.3x that or 56,550 psi.

35W

[M-Tecs]

According to the Commission Internationale Permanente pour l’Epreuve des Armes à Feu Portatives (C.I.P.), the maximum pressure specification for the .357 cartridge is 44,000 psi or 300 MPa 1. In C.I.P.-regulated countries, every pistol cartridge combination has to be proofed at 130% of this maximum C.I.P. pressure to certify for sale to consumers 1. Therefore, the proof pressure for the .357 cartridge is 57,200 psi or 395 MPa .