Tiered pressure ranges and modern specs

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Speaking of SAAMI and CIP, here's where the good stuff about dimensions and pressures can be located at their respective websites:

https://saami.org/technical-information/ansi-saami-standards/

https://bobp.cip-bobp.org/en/tdcc_public?page=1&cartridge_type_id=1

My favorite Hungarian guntuber included a visit to a CIP facility in this video (around the 15 minute mark) to demonstrate their process for checking old firearms:



[BTW, because Balázs is such a handsome dude with a charming accent, my wife will happily sit through his videos with me.]
 
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There’s a relatively strong argument that any .473” boltface (standard) cartridge chambered in a rifle which is also offered in .532” boltface (magnum) cartridges could also be loaded to 65kpsi. This comparison shows a THINNER barrel tenon could handle greater pressure, and obviously the action can handle considerably greater bolt thrust - so if the action and barrel can tolerate 64-5kpsi with 300win mag, why wouldn’t it tolerate the same for .30-06 cases? Are we really to believe a short action Rem 700, Ruger M77, or Win 70 can handle 62kpsi from 308win, but not more than 60kpsi from the 30-06 in a long action… which… naturally… tolerates 64kpsi from 300wm, with a 26% LARGER bolt face… 300wm is ~35% greater bolt thrust in the same action as a 30-06… pretty clear to see there’s more room above the 1906 pressure standard of the Springfield round. The same paradigm applies for these Mauser cartridges - there’s no reason to believe a Rem 700 long action in 7x57 has to be loaded to lower pressure than a 7-08rem in a short action 700 - or frankly, no reason it has to be loaded lower than max pressure for a magnum standard. Brass life in older case designs may be terrible but guys have done it long enough to provide empirical evidence that the cases won’t suffer catastrophic failures or cause sticky extraction just for increasing to 60kpsi standards in these stronger actions.

32 H&R has been another which guys seem to hotrod pretty heavily in modern Rugers. Guys have done pretty impressive stuff with some older black powder cartridges in modern actions as well, 38-55, 45-90/110, etc. Even 30-30 gets a pretty significant shot in the arm when chambered in a stronger action and loaded heavily.

460 Rowland is another example of a 45acp pressure standard, as is .353 Casull above the 357mag in 5 shot revolvers. I suppose “Casull level” 45 Colt loads could be considered Tier 4 of Ruger Only loads, only to be fired in 454 Casull Rugers - not sure the point, but it’s technically apt.

Maybe following a different turn - considerably more powder can be loaded into certain cartridges if the SAAMI max coal is ignored for firearms which allow such. For example, a guy can get enough H110 into a 44mag case to grossly exceed book maximum pressures if bullets are loaded to cylinder length in Ruger Super Blackhawks and Super Redhawks, greater than 10% increase in charge weight - and anecdotally, delivering lower maximum pressure than book maximum loads seated to the suggested COAL’s. This gets 300grn bullets well up over 1300fps, or even over 1400fps in 7.5” revolvers - maybe not raising a full level, but certainly vaulted ceilings above the typical 44mag performance.

So there are a lot of animals out there which have benefited from modern actions and modern understanding of pressure standards and firearms design - compared to what was “guarantee-able as safe in all actions designed 50-100+ years ago.”
You've probably read the 30-30 article on accurate shooter that got my gears turning on this.
 
I know 257 Roberts has two pressure levels. With the same case as a 7x57 Mauser I suspect it gives a starting point to work with. I know those were in deference to older Mausers and lever action rifles. My 257 is built on a Springfield 1903 action so I figure it can handle the higher pressures (and magazine length isn’t a problem), but there also isn’t much reason to push the boundaries. Can I push a 85 year old rifle harder? Sure, but I also have a 30-06 that can do that too.
So the moral of the story here is, as always at THR, when in doubt, you do need another rifle.
The question was more theoretical investigating the idea that the Sammi standard is whatever was submitted at the time of adoption not the realistic limits. These things are much higher on modern actions because the material strength and quality is much better. In absolutely no way am I questioning limits established in older arms but if one had a 280 built today, going +5000 psi which is spec for 280ai seems obvious. The AI has less barrel material for strength and cannot be superior in strength.
 
I am unaware of any tiered loads or recommendations for European firearms. And the reason is: Proof Testing. The European proof test program was specifically designed to remove old, unsafe firearms. That is why American's notice Norma 8 mm Mauser ammunition is a lot hotter than American made 8mm Mauser. Europeans have weeded out old, worn out military actions at the Proof House.

I only know a little bit about European proof testing. It used to be that a firearm or barrel could be not be transferred to a different person without undergoing proof. And from I read, the Proof Houses check dimensions, probably mechanical condition. If the firearm fails, at one time the firearms were chopped up. That might have changed, I read in a thread where the seller would be stuck with a rejected firearm or barrel.

The European system assumes the buyer is ignorant and needs to be protected, the American system assumes the buyer is an expert and knows everything.

You think American car inspection is bad, go to Germany. The Germans thoroughly check out your vehicle every year, inspectors have check sheets, they will require replacement of an emergency brake cable with external rust. If one tire needs replacing, you have to replace all tires, and you have to buy new German tires. No retreads, or crappy American tires. German highways do not have the tons upon tons of retread tire debris that American roads have. You drive into inspection, and you will come out with a list of things that need fixing. If your vehicle breaks down on the Autoban, you will be fined, no hugs, kisses or love for those with unreliable vehicles.
I've dealt with stupid smog checks on one side of the country and inspections in Connecticut. To be honest the car inspection is a good idea because bald tires in the ice and snow is a terrible idea and I've seen enough to know people don't self regulate well. I've read of proof houses and my issue with them is destruction of antique arms. Some historical guns don't need to be chopped up.
 
As a sort-of aside, I consider all of the dangerous game cartridges to be "two-tiered". It's the rare man who can tolerate dozens of full power loads from something like a .470 Nitro. The rest of us need low velocity loads for the majority of our practice, and I always have ammunition boxes marked "practice" and others marked "hunting".
 
The best modern example of my thought process is 6 ARC. Two different levels for different actions. No need for a different round, just get the platform that best suits your needs.
 
Most American state inspections are not safety inspections... they are revenue generators, that's all. Every once in a while you will find a zealous inspector, but by and large, it's a rubber stamp and off you go.

The primary purpose for European Proof Testing, American automobile inspections, and Certification training, to include Cosmetology degrees, is the revenue the requirement setters, the educators, and the requirement gatekeepers, make from these things. It is debatable whether there is a net benefit to society.
 
US SAAMI "8mm Mauser" is the ca 1920 8mm Remington Special, greatly underloaded for 1888s very early 1898s, and commercial guns like Haenel with 1888 type actions. I would not have thought there were so many being sold here as to frighten US ammunition companies. One conspiracy theory is that what they really meant to do was avoid showing the true capability of a funny furrin rifle and possibly hurting sales of domestic products.

Got to talk this year at a Regional to an Engineer who has "consulted" for a major arms importer and a major firearms manufacturer on product liability cases. Now the talk was between target changes and scoring, so I did not have a lot of time to pump for details. But he had consulted on a Gewehr 1888 accident. This Gewehr 1888 was made in Germany, sold to Turkey (I assume WW1) and yet was one of the rare Gewehr 1888's that had not been converted from 0.318 to 0.323. There is an extensive section on the conversions in German Military Rifles 88 and 91 Firearms V.2 by Deeter Storz The Germans made a good faith effort to convert all of them, but apparently a few stayed in the original caliber. The major arms importer did not check all their inventory for barrel diameter, sold one to some unfortunate, who shot standard .323 8 mm ammunition through it. I don't know if the ammunition was surplus (full power) or commercial. What did happen was the bolt shed its lugs, went through the shooters jaw bone, and through his shoulder. And I mean, all the way though. Obviously the shooter was angry, the rifle was sold as "8mm Mauser" and he had fired 8mm Mauser, and he was injured, and he sued.

I was more interested in the technical aspects of the investigation, which were big bucks the consultant paid for a rare and an all original 0.318 rifle for investigation and testing. And he said they did multiple tests, including crystallography. I wish I had a recorder, or a better memory, but this is all I remember. I do remember asking "So you have data?". Because I wanted to know the metallurgy, strength, etc of a GEW 1888. What bud said was interesting: "The lawyer has the information" . You want to work for a lawyer, you are going to sign non disclosure agreements.

I run into deniers all the time, these deniers claim old rifles are made from materials just as strong, if not superior to today's steels, and demand I prove them wrong. And the same people demand all the reports of these things blowing up, and since there are very few on the internet, claim worries about old action strength is a nothing burger. Well, there might be a very good reason why no one is putting information out in the public domain on the number of old gun blowups, and the injuries. Firstly, the people making money on this, are only making money out of potential Darwin award candidates and winners. They are actively waiting for people to injure themselves, or kill themselves. They have "their line in the water" so to say, and they only make money when something bites, and surprisingly, they get bites. They have absolutely no financial incentive to warn anyone about anything, not that the 50% of the nation who did not take their COVID shots would listen anyway. And of course, those selling these things, they also don't want bad information out there, they don't want to encourage lawsuits, and they sure don't want potential damage seekers learning from previous. I am confident that the defendants get the all court records sealed, and by design, the public has no idea of the frequency and severity of blowups.

The American public is ignorant by design, and by inclination.
 
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Speaking of which, the US 30-06 M2 cartridge was deliberately downloaded from M1 specifications due to concerns about the latter exceeding the safety specifications at many military firing ranges. The stated maximum range of the M1 cartridge out of the M1903 was 5,500 yards vs. 3,450 yards for M2 ball (FM 23-10 1943, p 212.)

As I recall, the main way .30 M2 was "downloaded" vs M1 was by returning to the 150 gr bullet as used 1906-1925.

I know 257 Roberts has two pressure levels. With the same case as a 7x57 Mauser I suspect it gives a starting point to work with. I know those were in deference to older Mausers and lever action rifles. My 257 is built on a Springfield 1903 action so I figure it can handle the higher pressures (and magazine length isn’t a problem), but there also isn’t much reason to push the boundaries. Can I push a 85 year old rifle harder? Sure, but I also have a 30-06 that can do that too.
So the moral of the story here is, as always at THR, when in doubt, you do need another rifle.

The .257 Roberts is just weird. The usual excuse for it being loaded to even lower pressure than the parent 7mm does not hold up The .257 Remington Roberts is not the same as the wildcat .25 Roberts (either of two versions) and will not chamber in whatever Spanish Mauser or low number Springfield that Niedner or Griffin & Howe might have worked on.

This Gewehr 1888 was made in Germany, sold to Turkey (I assume WW1) and yet was one of the rare Gewehr 1888's that had not been converted from 0.318 to 0.323.

Being reluctant to spend $130 for details, I recall that the German military conversion of 1888 and early 1898 rifles to 7.92 x 57 IS was by reaming the chamber neck so the .323" bullet would release from the case neck - our old buddy Clark blamed excessive pressure on "bullet pinch" not bullet diameter - and a tapered throat to gradually swage said .323" bullet down to .318" or so. I know of nothing to say they "freshed" the entire length of the barrel to a larger diameter.

It would be interesting to know what really wrecked that 88, but NDA...
 
As I recall, the main way .30 M2 was "downloaded" vs M1 was by returning to the 150 gr bullet as used 1906-1925.

Here's a photo of the respective bullets M1906, M1 and M2 ball ammunition for comparison:

3006m1m2.jpg

If Wikipedia has it correct (for once), there was also a different propellant specified for each of these three cartridges.

I believe the muzzle energy and pressure curve remained essentially the same with M1 and M2 ball, since the M1 rifle was developed during the heyday of M1 ball ammo. Perhaps the term 'ballistically downrated' would be more correct than 'downloaded'?
 
Oh, yes, there was a whale of a lot of propellant development in those days, early AP was very hot and M1 did not quite make the original spec. But by WWII, 4895 was giving standard velocity at substantially lower pressure.
 
Maybe it's just me but I believe that if you want a certain cartridge to go faster than intended you should just upgrade to a cartridge designed to do that. Especially in vintage weapons. I understand hot rodding cars and motorcycles, done that. I value my handsome face (LOL) to much to do it with guns.
 
Oh, yes, there was a whale of a lot of propellant development in those days, early AP was very hot and M1 did not quite make the original spec. But by WWII, 4895 was giving standard velocity at substantially lower pressure.

For those unfamiliar with the story, postwar surplus 4895 was also the making of Bruce Hogdon's company -- he started his company with the purchase of 25 tons of the stuff in 1947.
 
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I knew that, but I was wondering the last time the Great Internet Exposition of Bulk Powder vs Canister Powder + Lot Variation came up, how long did that 25 tons last him? That would likely have been a 50000 lb carload lot and therefore quite uniform.
OK, what next?
Did he get more surplus and lucky that it was the same or near identical production run?
Did he get more surplus and back blend it with what was left of the first?
Or did he go straight to foreign copies?
 
Read the first post and immediately thought of the 257 Bob, 8mm mauser US/Euro loadings, the 38 super and the lowly 22lr.

I have a couple of "parlor" rifles that need the std velocity or they spit gas or pop open if fired with a Hi-vel load.
 
Maybe it's just me but I believe that if you want a certain cartridge to go faster than intended you should just upgrade to a cartridge designed to do that. Especially in vintage weapons. I understand hot rodding cars and motorcycles, done that. I value my handsome face (LOL) to much to do it with guns.

Especially with the small advantage it gives you. I checked estimates for a 7x57 at each level with 139gr Hornady:

65000 psi: 3010 fps
CIP max: 2900 fps
SAAMI max: 2810 fps

So you increase pressure by 27% over SAAMI, but in the end it's only 8% more powerful than at CIP max, and 15% more than SAAMI.

For a modern rifle there should be no problem with modern loads, but in an antique I don't see the point of pushing it. But people do it, in ancient rifles, all the time!
 
I knew that, but I was wondering the last time the Great Internet Exposition of Bulk Powder vs Canister Powder + Lot Variation came up, how long did that 25 tons last him? That would likely have been a 50000 lb carload lot and therefore quite uniform.
OK, what next?
Did he get more surplus and lucky that it was the same or near identical production run?
Did he get more surplus and back blend it with what was left of the first?
Or did he go straight to foreign copies?

Assumed you already knew the basics about this :)

For any questions not covered in this published account, your guess is as good as (or probably better than) mine:

https://www.americanrifleman.org/content/hodgdon-the-inside-story/
 
So you increase pressure by 27% over SAAMI, but in the end it's only 8% more powerful than at CIP max, and 15% more than SAAMI.

Never mind CIP, looking at SAAMI vs SAAMI
There was once, before computer estimators, a rule of thumb that an increase in powder charge would give you a proportionate increase in velocity but at the cost of twice as much pressure. +27% pressure +15% velocity, close enough.
 
That is why most reloaders prefer CIP. Anyone with access to old Load Manuels, compare some loads to to the modern Manuel’s. Many of them you’ll find a large differential.

Like most things, SAAMMI & even Reloading has been sissified!
 
I have a 280 AI that I built 3 years ago.The SAAMI spec is 65K.The 280 Remington is supposed to be 60K.As I understand it,the 280 Rem. was held to a lower pressure because it was loaded in the semi-automatic M740 and they kept the pressure down to make sure the 740 didn't have extraction problems.But they also loaded the 270 which is the higher pressure.My first 280 was a custom 700 with a Shilen barrel and I loaded it quite a bit hotter than the manuals called for,knowing the data was on the light side.I never had problems with it,and the same loads were shot in it until the throat was gone.It held up for more than 3,000 rounds.Would it have lasted longer had I not loaded it like I did?Probably a little bit.Now it's a 280AI,and I'll be doing good to live long enough to shoot it out again.
 
That is why most reloaders prefer CIP.

And why is that? It doesn't matter whether a cartridge is specified by CUP or pizeo psi; SAAMI or CIP. If Manuel says 50 grains of Acme 3995 is maximum, it doesn't matter whether it is shown to give 50,000 CUP or 60,000 ppsi, or 4150 bar, that is the place to stop.
 
And why is that? It doesn't matter whether a cartridge is specified by CUP or pizeo psi; SAAMI or CIP. If Manuel says 50 grains of Acme 3995 is maximum, it doesn't matter whether it is shown to give 50,000 CUP or 60,000 ppsi, or 4150 bar, that is the place to stop.

Not CUP (Copper Unit Pressure). C.I.P. (The Commission Internationale Permanente). The European equivalent of SAAMI. You will find, while SAAMI stops cartridges short in pressure (again, standards have changed over the decades. Manuals showed max loads using a bit more pressure in the 60’s, 70’s.), CIP shows max safe loads at higher pressures.

Too many Snowflakes & Lawyers involved with SAAMI I think.
 
"Data" from the 1960s - I started in 1970 with Lyman and Speer - does not include pressure readings. Real guns are cited in velocity tables, no indication that bullet companies had PV equipment. You can "work up" to a higher load without "pressure signs" when you are not bothered with pressure readings.
 
Never mind CIP, looking at SAAMI vs SAAMI
There was once, before computer estimators, a rule of thumb that an increase in powder charge would give you a proportionate increase in velocity but at the cost of twice as much pressure. +27% pressure +15% velocity, close enough.

Down the rabbit hole we go discussing pressure.

Make no mistake CUP, CIP, BAR and PSI are all different units of measurement to define pressure and can vary wildly when trying to find a correlation between any of them. You can get close but it isn't perfect science by any stretch of the means.

The same can be said about other units of measurement. What is the correlation you ask? Take a look at converting metric to inches and that is the point. You can get close and sometimes exact. But the point is not always. They are two completely different units of measurement.

When referring to load data there is a lot of information that often gets mis-understood especially when comparing published data between bullet manufactures and the dates of publication not to mention typo's that occurred at the time of publication of said data. More to the point the chambering that the individual is referencing as it pertains to starting loads and maximum loads will vary sometimes greatly even by the same author of his or her own published data.

Here are 4 different publications that I have on hand to demonstrate what I am taking about. Hornady's handbook of cartridge reloading 2nd edition and the 9th edition, Modern Reloading second edition by Richard Lee, and the 49th edition of the Lyman reloading handbook.

No where in Hornady's manuals/books are there references to pressure or units of measurement to define pressures in the published tabulated data tables listed in these books. For example on pages 334 and 335 of the 9th edition of the Hornady book the only things to be gathered by the data tables are: bullet type, built weight, sectional density, diameter, ballistic coefficient or BC, powder charge measured in grains and estimated muzzle velocity measured in feet per second or FPS. The same can almost be said for the 2nd edition, It has a lot less information.

Now in the Lee manual there is some of the same information and a lot of different information to be had. For example on page 249 in the Lee manual pressures are referenced in CUP and PSI along with a whole lot more data.

Lets take a look at the Lyman manual. For example on page 225 in the Lyman manual pressure is defined in both units of measurement CUP and PSI.

The Lee and Lyman manuals use both of these measurements yet some of the data is different. Why? The answer seems easy different authors, atmospheric conditions, equipment used and elevation are just some of the reasons that could be a factor. Other than those speculations I have no idea.

What is the point? The point is the numbers can vary greatly and one can misinterpret what is written in the published data. Why is this important? Because many of us load for firearms or use what may be considered obsolete where too much pressure or even too little pressure can be detrimental to both the user and the firearm. Confuse one measurement with the wrong powder charge and KAABOM!!! You've just detonated a bomb in your hands potentially near your face and others around you.

With all that said the references that I have mentioned are all filled with great Information and where one may fall short the other makes up for it. That is just my honest opinion.
 
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