Found this 9mm Luger ammo vs 9mm

[Kyrie]

Originally Posted by Rick W.

Over the years, I have often wondered about the SAAMI organization and its functions in the states. Is it a mandate or a suggested set of data?

The Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) is a private organization created in 1926, recognized by the American National Standards Institute (ANSI), and privately funded by companies, organizations, and individuals with an interest in the manufacture of sporting arns and ammunition.

SAAMI serves as the clearing house and reference center for the data need to insure uniformity of firearm critical dimensions and the uniform compatibility of the ammunition manufactured to be used in those firearms.

Firearm/ammunition manufacturers’ adherence to SAAMI manufacturing data is voluntary.

Originally Posted by Rick W.

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The 754-776 is the go and no go chamber dimensions, take a reading on your gages.

Actually, no. These are the inch pattern lengths of the GO and FIELD REJECT headspace gauges. There is no SAAMI standard for a “NOGO” gauge.

Originally Posted by Rick W.

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Of course, our friends across the big pond have their own version of a controlling or voluntary mechanism.

For most of western Europe countries (the EU in particular), this is Commission Internationale Permante Pour L'Epreuve des Armes a feu Portatives (C.I.P ). That’s also true for the arms/ammunition manufacturers in other countries who wish to market to those countries who are signatories to C.I.P.

For C.I.P. signatories, C.I.P. standards are supposed to be legally obligatory. The degrees to those obligations have been observed has varied from country to country, and from proof house to proof house, and from time period to time period.

At the risk of blending threads, C.I.P. and NATO have a lot in common when it comes to making and complying with agreements.

[Rick W.]

I always had the concept that the SAAMI deal was voluntary. Voluntary from a business sense I guess.

Most of the reamer vendors offer go, no go, and field gages. I have never seen a field gage in the hand, only in pictures. I measured a set of 9mm gages a while back, curiosity you know, and they measured 754 and 776. Were marked go and no go..............go figure huh?

I was surprised that the European standard was tighter between the go and no go(some slack please). In today's environment, tis probably the more better spec to me at least.

Maybe some poetic license or semantics by us in the colonies huh?...

[Kyrie]

Rick,

US arms/ammunition manufactures compliance with SAAMI is legally voluntary. The US, unlike most EU countries, has no set of proof laws and no government established and run proof houses.

Generally speaking, those (mostly European) countries that are signatories to the C.I.P. agreement have internal laws that require, by statute, adherence to C.I.P. standards as a prerequisite for any firearm/munition to be legally offered for sale in commerce (sometimes including export - even export to countries that are not C.I.P. signatories)

On the subject of head space gauges and how vendors mark them, vendors can do just about anything they want. Ultimately it's up to the people who need to use to head space gauges to understand what the gauges measure, and to understand and appreciate the potential problems of firing SAAMI compliant ammunition in a chamber that is not SAAMI compliant (e.g. chamber is too short as revealed by failing to close on a GO gauge, or chamber is too long as indicated by closing on a FIELD REJECT gauge).

The NO GO head space gauge has some arbitrary length between the lengths of the min (GO) and max (FIELD REJECT) lengths of a chamber. It is really only useful for hobbyist reloaders who reuses fired cases, and especially the hobbyist who intends to reload a fired case more than once.

Reloaded ammunition that is intended for use in a firearm that passes a FIELD REJECT gauge but fails a NO GO gauge should be neck sized only and never, ever full length resized. Full length resizing a case progressively thins the cartridge case wall (esp. the case wall just ahead of the case web). This thinning of the case wall progressively, with each incident of full length resizing, increases the potential for a catastrophic case failure that dumps the chamber pressure out of the firearm's barrel into the slide and frame of the firearm. That's how people lose fingers, or hands, or for the very unlucky their lives.

A chamber that has distal end of the head space datum line beyond that length expressed by a NO GO gauge significantly increases the risk of case failure with reused cartridge case, and greatly increases the risk of case failure for cartridge cases that have been full length resized.

The intersection of chamber head space, cartridge case length relative to the head space datum line, the effects of chamber pressure on the cartridge case of a round of ammunition when that round is fired, and the reuse of cartridge cases is a profoundly complicated discussion. The above comments only scratches the surface of that discussion and should be read with the understanding it's a small part of a much larger subject.

[Kyrie]

Found the TM I'd mentioned earlier.

Here is the TM page for commercial 9 mm Luger ammunition. I've boxed in red the info I thought especially interesting:



And here is the page for the US army rendition of 9 mm Luger, a la NATO:



If we were to take the data from these two pages at face value we would have to conclude US army 9 mm Luger NATO is the weak sister of US commercial 9 mm Luger.

But there is a potential problem lurking here; the TM doesn't tell us whether the same test method and procedures were used to produce both sets of data.

If both data sets were determined using the same methods/procedures then the data sets are comparable and US army NATO is slower and has a lower chamber pressure than US, SAAMI compliant, 9 mm Luger.

If both data sets were not determined using the same methods/procedures then the data sets cannot be meaningfully compared. While we still have the caveat from page 12-3 that use of commercial 9 mm Luger is not authorized in the M9 pistol and what that caveat implies, the pressure/velocity data sets just can't be used to draw any comparative conclusions.

Such is the wild, and sometimes counterintuitive, world of internal ballistics :-)

[Mark1]

Some interesting information and comments in this thread.
The original article referenced at the beginning of this thread is nonsense. There is no straight-walled 9mmx19 cartridge and pressure differences are to be expected when 2 organisations are testing using different methods and equipment.
As Rick W noted, I commented a while ago on a thread by member GT who was having problems with a P08 rebarrel job.
My suggestion was to use CIP Standard headspace gauges because they are made to a headspace tolerance of 0.012" whereas the SAAMI type are to a tolerance of 0.022". This difference occurs with most calibres and for that reason I would always recommend that the CIP standard be the first reference where there is a problem or discrepancy.
The CIP is a regulatory authority and the standards published by them have the status of law in the CIP signatory countries. No ammunition may be sold on their commercial markets which does not meet all aspects of the standards and is so marked.
The SAAMI is an association of companies which publishes recommendations for dimensions and pressures of ammunition. Compliance with the SAAMI standards is entirely optional in the US (and NZ), even for companies who are members of SAAMI. Also there is no requirement to identify which ammunition does or does not comply with the SAAMI standards.
As Rick W noted previously, it's really 2 different approaches.

[Kyrie]

I have a little different view on C.I.P. vs. SAAMI, and on whether to use C.I.P. or SAAMI compliant head space gauges for any specific task.

I'll share those views, purely FWIW.

C.I.P. standards are supposed to have the force of law in those countries who are signatories to the C.I.P. agreement. But in actual practice there is no force of law applied. More than one C.I.P. signatory has a history of fudging actual adherence to C.I.P. and sometimes simply ignoring C.I.P. standards. Structural problems within the C.I.P. organization and the sovereign powers of C.I.P. signatories make this evasion/disregard for C.I.P. standards difficult to detect and impossible to prevent.

SAAMI, OTOH, is admittedly voluntary, and (largely) funded by and run for the major US arms/ammunition manufactures. That’s why I trust those major manufacturers to be SAAMI compliant; no viable business ignores the expensive consultative service they have paid to create, and continue to pay to function every business day.

On the subject of C.I.P. and SAAMI head space gauges I tell people who are sufficiently concerned with the head space of one or more of their firearms to want to buy (or rent) head space gauges to check head space to get the head space gauges that are compliant with same system as the ammunition they intend to use.

As a real life example of this, I recently bought a CZ model 455 .22 rimfire rifle. I also bought, at the same time, two interchangeable barrels; one barrel chambered for the .22 Winchester Magnum cartridge and the other barrel .17 Hornady Magnum, all of which let me choose whether I wanted to shoot .17 HMR, .22 WMR, or .22 S/L/LR in that rifle. I plan on shooting nothing other than SAAMI compliant ammunition in this rifle, so I made sure I had SAAMI compliant .17 HMR, .22 WMR, or .22 S/L/LR head space gauges. Every time I change barrels I check headspace to be sure I haven’t committed canine carnal knowledge when I did the barrel change, and to be sure ammunition and chamber dimensions are a safe and functional match.

Just an account of my choices, and a little background on why I made those choices the way I did.

[Patrick Sweeney]

Just to add a bit more confusion, the 9mm case, since it is tapered, may or may not headspace on the case mouth. The case is a cone, going into a cone-shaped hole. When the two cones meet, the case stops, whether the case mouth has reached the front of the chamber or not.

And Kyrie, where did those pages come form Did the Army really print technical data on 9mm cartridges that lists the bullet weights as 182 and 179 grains?

Finally, the MAP, Maximum Average Pressure, is a ceiling, not a goal. If an ammo maker can get the velocity they want, at a lower pressure, they will. So, if the goal is (for example) a 115 grain bullet, at 1,200 fps, and they can do it with the powder you have, at 27,000 PSI, then they'll do it.

[Rick W.]

When I started rebarreling Lugers for my needs/wants, I went out to SAAMI to see the numbers on the 9mm and 30 Luger. The go and no go limits on one was over 20, the other was 10. Always thought that was a little odd, but not much influence as I was taught to stay at go or go plus some(some is a relative term I know, but depends on environment)

I have noticed a lot of 9mmx19 range brass being short of the 745 9mm SAMMI number, but guess that they are interested mainly in one time compatibility. The reloaders are a small market comparatively.

In coming up thru the ranks of hard knocks, I have come to kinda like when things are intended to work together. When the chambers are cut appropriately, the sized case is long enough, overall length is there, and the pressure is semi-sane, whether factory whatever or handloads, the pistol is a joy to shoot, no muss; no fuss; just an enjoyable experience; just works.

My thanks to Mark for his comments on the tighter spec.

I learned under some benchresters, fussy types, knowledgeable. Not seen two guy argue over 2 thousandths of length for hours on end before, but just their nature. Cannot say too much against their successes. All in all, everything has its place....and time. One has to ponder a lot of things in life and see what works for them.

The 20 in the 9mm spec is almost half of the firing pin total protrusion in some things, so one thinks things could get dicey in ignition if nothing else.

Rimfire is mostly done with the rim. Lots of available vendor dimensions there, some in the mid 30's on rim to mid 40's on the rim, so a victim of circumstance as Curly would say about finding the right 22 ammo for the right rifle/chamber.

One notes in rimmed with cases with shoulders, like the 22 hornet or its wildcats, headspacing on the rim becomes a search for the right lot of ammo with reloading intents. The sharper shoulder of a hornet wildcat seems more flexible and works with the reloader type.

I have a Ruger No.1 mule as I call it; maybe 10 barrels for it. It has been everything from a 17 bumble bee to a 375 H&H. Being a packrat, I still have all the barrels, so one can screw on the barrel, check the index mark, and the extractor number.............and go shooting. These are threaded actions of course. The actions like Savage, and the rimfires, are pretty flexible as to headspace and even gapspace, and take the extra tooling.

The clowns that I know that do custom chambering, know exactly what the headspace is going to be after torquing down, they measured it with a nice depth mic on the action and holding feature face. They use gages to double check their work and for liability requirements. Odd one can measure to a tenth, but use of a simple gage trumps all in some circles. Then there are the guys that use no gages, because their cartridges are not on the list............but I have a nightie that they know how. Obviously there are guys that gunsmith beyond their capabilities as well.......The more knowledge an individual has, the more clear some things become.

I do not know if SAAMI updates old cartridge info with current manufacturing. I would doubt if the establishment moves much. The 35 Winchester Legend was just added as a new case recently.

I think everyone is on the same basic page. Be safe and likes performance.

[Kyrie]

Originally Posted by Patrick Sweeney

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And Kyrie, where did those pages come form

Technical Manual number is at top, right, corner of each page.

Originally Posted by Patrick Sweeney

Did the Army really print technical data on 9mm cartridges that lists the bullet weights as 182 and 179 grains?

No sir, they did not. But they did list the cartridge weights as 182 and 179 grains :-)

Originally Posted by Patrick Sweeney

Finally, the MAP, Maximum Average Pressure, is a ceiling, not a goal.

Correct. ANSI/SAAMI Z299,3 – 2015 “Maximum Average Pressure - is the recommended maximum pressure level for loading commercial sporting ammunition.”

Originally Posted by Patrick Sweeney

If an ammo maker can get the velocity they want, at a lower pressure, they will. So, if the goal is (for example) a 115 grain bullet, at 1,200 fps, and they can do it with the powder you have, at 27,000 PSI, then they'll do it.

Correct. Some people confuse the SAAMI MAP with a “service pressure”. That is not the case, and “service pressure” doesn’t even exist as a concept in SAAMI. Moreover, some people tend to equate higher peak chamber pressure with higher muzzle velocity. That may or may not be true in any specific case. Muzzle velocity and peak chamber pressure are only vaguely related, and in some cases may actually be inversely related. Peak chamber pressure is not a good predictor of muzzle velocity.

SAAMI has performance as the goal, with that stated performance to be attained without exceeding some stated average peak chamber pressure (“Maximum Probable Sample Mean"; MPSM).

[Jasta2]

Boy, my suggestion on reading that article sure has brought some detailed responses!! Tried to absorb much of it, but left my head spinning at times!