If the SAMMI specification on a cartridge is 62,500 psi or CIP at 53,000CUP is that considered HIGH pressure or NORMAL pressure. When we speak of high/low pressure are we saying above/below the benchmark pressure or are we picking an arbitrary number for comparison?

55cup or 62500ish is certainly high pressure.. but NOT the pressure of the wsm/rum (65000) or the 338 lapua, 68,800psi.

44kcup is mild

38kcup is low

in rifles

Who the heck is Sammi, and what does he know???

The "Sporting Arms and Ammunition Manufacturers’ Institute", otherwise known as SAAMI is the U.S. organization that registers the specifications for ammunition as a member of the American National Standards Institute (ANSI). Not just pressure levels, but also cartridge and chamber dimensions. They are also the organisation that preempts the FTC from regulating firearms & ammunition as consumer products. Most factory cartridges are so registered, but some propriatory cartridges like the Lazzeroni and Dakota cartridges aren't because the companies aren't members of SAAMI. (A-Square was/is? and registered the 500 A-Square as well as the 338/06).
In Europe, an organization known as CIP (IIRC committee international protocols, but in French) does the same, but by law you MUST register your cartridge dimensions etc. with them before you are allowed to sell any ammo or firearms.

For rifles, cartridges like the 45-70, (28,000 psi) 30-30 (42,000 psi) and 257 Roberts (54,000 psi) have lower pressure levels. The newer cartridges like the WSM series typically use much higher pressures (60,000+). Same with pistol calibers, 45 Colt (14,000) & 45 ACP (21,000) are low pressure, magnums (35-36,000) have more and the newest like the 500 and 460 from S&W go up to high rifle pressures (60,000+ psi).

"C.I.P." is short for "Commission Internationale Permanente."

The SAAMI and CIP pressure standards are maximum AVERAGE pressures allowable, whether specified in CUP or PSI.

The .338 Lapua Magnum is both SAAMI and CIP governed, and is seldom loaded to such a high pressure as specified here, but the brass can sure handle that pressure well.

At RIPoff Arms we try to keep pressures down to 60,000 PSI Average SWAG, with the entire line listed below.

Rip,
all new saami and CIp are psi, and only the older admissions are in CUP.

jeffe

Yes, jeffe, everybody knows that, don't they?
Peizo psi is an advance. I wish they would get rid of all the old CUP data.

Rip,
I agree, was just clearing the point.. and YES, no "cup" pressure should ever be reported, ever again!!

jeffe

Small point, but not trivial.

SAAMI measures pressure halfway down the body of the cartridge, C.I.P. measures at the mouth.

If you wish, I can send a copy of the SAAMI protocol. It is more difficult (i.e. costs $$) to obtain the C.I.P. protocols. There is a CD I bought from Triebel called "Patron und Lagermasse" that provides C.I.P. numbers for a host of cartridges, but does not delve into the specifics of the measurement protocol.

If anyone has any information on that topic, please PM me.

LD

Yeah I knew what SAAMI was but it was misspelled SAMMI. I asked as kind of a joke but nobody seemed to catch it. Oh well, gave everyone a chance to show what they know.