9mm pressure specs - SAAMI vs. CIP

[Halo]

A post in another thread got me thinking about this again, and you do see this question crop up frequently in one form or another.

Do SAAMI and CIP have different specifications for the maximum pressure in 9x19? SAAMI standard pressure 9mm is 35,000 psi. What about CIP? I've read elsewhere that CIP specifies approx. 38,000 psi for 9mm, which is close to what SAAMI considers +P. That's just the figure I've read on various Internet forums -- I've yet to find the definitive answer published by CIP.

So, is the SAAMI spec for 9mm truly "dumbed down", or is that just a myth?

 

[AK103K]

Best I've been able to determine is, they each have their own method of determining "pressure" and so far, I havent been able to find an "equivilency", or any info on how one system equates to the other. The pressures may appear different, but no one seems to be able to tell for sure that they are or not. They may well both be the same, or maybe they are different.

I tried to download the CIP info, but the files seem to be corrupt, or at least the ones I kept downloading were. Does anyone have a copy?

 

[rcmodel]

they each have their own method of determining "pressure"

That has long been my understanding also.

I don't know of any rule to compare the two, and more then likely there isn't one.

If we measure "here", and they measure "there", different powder burning rates would all give different results "here" & "there"!

rcmodel

 

[Gun Slinger]

Both systems obtain pressure measurements from different locations on the case. I doubt that they are "convertible" by equation from one system to another, but either system is within the range of safety of most 9mm firearms used here. While SAAMI +P ratings most likely exceed CIP ratings (by a small margin), either system is accepted as proven and safe.

A while back, I had the opportunity to run some foriegn made and domestic 115 and 124 FMJ over a chronograph and found little difference between them in velocity delivered out of a brand new Glock 17 with a 4.49" barrel. All performed very similarly and the Czech made S&B 124 gr. FMJ produced the lowest velocity (1066 fps) of all the loads tested with very gentle recoil despite an advertised velocity of 1280 fps. (out of a 7.8" barrel). The "speed demon" of the group was the Winchester 115 FMJ which porduced an average velocity of 1180 fps.


Domestic ammunition:

Remington UMC 9mm 115 gr. FMJ
HI: 1181
LO: 1132
AV: 1161
ES: 49
SD: 13.50
N: 30

Winchester USA 9mm 115 gr. FMJ
HI: 1235
LO: 1116
AV: 1180
ES: 119
SD: 22.01
N: 48

Winchester 9mm NATO M882 124 gr. FMJ (WCC00K033-008)
HI: 1150
LO: 1068
AV: 1113
ES: 82
SD: 20.09
N: 44


Foreign ammunition:

Sellier & Bellot 9mm 115 gr. FMJ (Czech)
HI: 1247
LO: 1076
AV: 1173
ES: 171
SD: 42.17
N: 75

Sellier & Bellot 9mm 124 gr. FMJ (Czech)
HI: 1104
LO: 1042
AV: 1066
ES: 62
SD: 16.49
N: 46

Magtech 115 FMJ (Brazilian)
HI: 1142
LO: 1097
AV: 1055
ES: 45
SD: 23.37
N: 15

From my testing it appears that the US made ammunition is a little 'warmer'.

 

[Halo]

Interesting results. It appears the popular notion of European 9mm ammo being "hotter" is probably untrue.

I think I might need to bust out the chronograph and run some similar tests. I'll be aiming for large values of N.

 

[Ol` Joe]

CIP max pressure for the 9mm is 39,200 psi piezo
SAAMI max is 35,000 psi piezo / 33K CUP

SAAMI normally measures pressure about midway in the case body and CIP usually at the cartridge mouth. The two pressures are different and measured at points in the chamber.
I have heard CIP is changing some of their measurement proceedure but, I can`t verify it.

 

[R.W.Dale]

I think there is bit of confusion here. Euro commercial 9mm ammo may not be any hotter than domestic loadings. But some European NATO 9mm is a great deal spicier. I chronied some of the infamous subgun ammo in a Hi-Point carbine that was getting real close to 1600 fps

 

[Halo]

Krochus the only disagreement I have is that there is no bit of confusion here, there's a whole lot of confusion here!

I guess the crux of the confusion stems from one basic question, does the SAAMI specification allow for 9x19's full and intended potential, or does it impose a handicap not found with the European ammo?

 

[R.W.Dale]

I guess the crux of the confusion stems from one basic question, does the SAAMI specification allow for 9x19's full and intended potential, or does it impose a handicap not found with the European ammo?

Well correct me if I'm wrong but here you have +p and +p+ ratings to even up the score so to speak

over there you simply have 9x19

 

[Halo]

True enough, and that does sort of underscore the difference between our ammo and theirs. What SAAMI would call above-normal pressure, CIP would call ordinary.

 

[FEG]

This is geared towards CZs, but the discussion of SAAMI (psi) and CIP (MPa) is generally applicable.

http://czechpistols82792.yuku.com/topic/14691/t/What-Types-of-Ammunition-Are-Safe-in-My-CZ.html

Bottom line: CIP 9mm maximum pressure is almost identical to the SAAMI +P maximum. In practice, most commercial ammunition, whether conforming to CIP or SAAMI regular (not +P) standards, runs at about 33,000 psi. Stated another way, foreign commercial ammo like Sellier & Bellot may be slightly warmer than Win USA or Remington UMC, but not by much. Standard commercial loadings (range ammo) are nowhere near the true potential of 9x19mm Para, no matter who manufactures them.

 

[Gun Slinger]

Interesting results. It appears the popular notion of European 9mm ammo being "hotter" is probably untrue.

I think I might need to bust out the chronograph and run some similar tests.I'll be aiming for large values of N.

Halo,

How large of a sample population are looking to achieve?

Please make sure to post the results here when you have them available.

I am not surprised that the CIP regulated stuff might be running a tad hotter than the domesticaly produced ammo, but I've yet to see anything concrete from the testing that I have done.

Of course, I don't have any Hirtenberger L7A1 either...

 

[Halo]

The value of N has a direct dependence on the value of B, which is my bank account balance.

Actually I would like to sample about 100 rounds of each type, though even then the data would be of limited value since the population would probably be confined to the same lot number.

I still have a few hundred rounds of Geco 124 grain, from Germany, and subjectively it always felt like it had a little more pop to it, but I never chronographed any. I'll try and do a 50 round sample this weekend just to see how it squares up with the results you got.

 

[Gun Slinger]

Sounds great. I have always wondered about the Geco ammo.

I feel you on the value of B brother. It ain't cheap no more!