Pressure limits in older european calibers, - do they make sense with modern actions and brass??

[Scipio]

Hello everyone, This is a interesting subject, so here is a dedicated thread to it (This also allows the 7x68s thread to retun to it's original subject)

a few posts from the 7x68 s thread to get us started:

Of course if a manufacturer has already a stronger brass as their standard in the 257 the +P might be the same case just with the +P stamped. That is up to the manufacturer, he carries the responsibility. As a user you might not know that it is the same. If it goes bang and you run a cartridge over it's pressure limit it is your responsibility. Yes a 6mm rem and 7x57 might or might not have the same web. If you can guarantee it then ask for the reloading manuals to be changed. You must just make sure all brass manufacturers got the memo.
Very simple actually:
The cartridge case manufacturer must guarantee the case can take CIP/SAAMI rated pressure.
The reloader must or should guarantee to not exceed max CIP/SAAMI rated pressure.
The shooter must know that his firearm is able to take the rated pressure, for example CIP proofed.
It is all about who is responsible for what. Which judge is going to be convinced by "Harrygrey said it will be fine"???
edi

What happened to people taking responsibility for their actions - the US ambulance chasing ideology of someone else always being responsible is a large part of our current predicament. If someone is going to take a random forum poster’s posts as gospel and blow themselves up - they are the one who’s responsible for their own actions. I’ve always said it’s up to people to do their own research and come to their own conclusions based on many sources of data, and they must make a judgment on what is logical. That’s why i like to correct technically inaccurate statements like modern 7x57 brass being weaker than 6mm rem brass and not able to take the pressure. But of course if I read that somewhere I’d want something beyond my statement. Ive said it before and I’ll say it again - blindly following rules without any understanding for their basis is just as dumb and almost as dangerous breaking them. You should have a thorough knowledge and understanding of pressures before you start reloading- and this gives you the judgement to break them if needed in exceptional circumstances. A bit like the speed limit. Would you say it’s unsafe to exceed to the SAAMI pressure limit for 45-70 when loading for a Ruger no1?

Here’s an interesting thread by a bloke who cuts a lot of different cases up and finds no correlation between web thickness and pressure rating.

Also, you say you must shoot a CIP/SAAMI proofed rifle - what do can shooters do outside of Europe and the US? New guns do not require proof in Australia - literally not one single custom built firearm built in the country has been proofed, there is no proof house. Is this a dangerous situation? I’d guess there are more recreational firearms and shooters in aus than the UK. I’ve never heard of a rifle blow up caused by shoddy gunsmith work here and the media just love anti gun stories

Harry, we live in the sticks and don't even sell guns, yet we have one blown up Rem 700 that even damaged the bull barrel (according to London Proof house), have two stocks that guns blew up in and a crack in a bolt from a Ruger M77 after overload and case rupture. Every country has it's own laws. However every country has laws. Deliberately overstepping reloading or manufacturers guides/ manuals won't make a good impression after an accident. Rifle manufacturers work to SAAMI/CIP or possibly their own countries spec everywhere in the world, proofing is only a check step.
So tell me where do you draw the line when it comes to pressure? Willi nilli whatever you think? copy pressure from a different cartridge? All cartridges are equal?
You say that you corrected a statement that one case is weaker than another just because they have different max pressure ratings by CIP&SAAMI. Well with what authority can you make that statement? One case is built to one set of rules, the other to a different set of rules and you try to tell us that they are the same? In future also? From every manufacturer? BS.
The actual question is why? Why can one not accept the rules of each cartridge, just get a more powerful cartridge if the performance does not match expectations.
edi

sorry Claus, it is a bit of a sidetrack. But I feel it is still relevant - about the modern use of old style cartridges and case design.


I’m not sure where you pulled the willi nilli bit from - I was clearly pointing out a specific example with very well grounded logic. We’re not school children here, and don’t need addressing like them. I have to admit in general I follow the min and max powder capacities published for cartridges, because they are mostly good guidelines. However, there are - like everything in life - exceptions. In general people who make comments of absoluteness appear arrogant, ignorant, stupid and foolish. I pointed out some exceptions - and that SOME (not all) CIP and SAAMI specs are outdated and now arbitrary. Such as the pressure limit for 7x57 when used in anything but antique firearms. The brass is the same as 6mm Remington brass, as I have pointed out (I have pictures on the way if he can fish the evidence out of the bin - have a mate who cut a few different cases last night and confirmed identical web thickness between them under a 4x lens. I also consulted 6mm rem shooters who confirmed they were on average the same and +p 257s were generally no different to regulars). You claimed they were different cases with different design and thickness - it has since come to light this was pure uninformed speculation with you trying to falsely backup your flawed argument.

Yes some cartridges were re-designed for higher pressure (eg 338 lap from 416 Rigby - a cordite specific case), but it doesn’t follow that all others were. Eg 270 (65k psi) used 30-06 (60190 psi) cases, 6mm rem (65k psi) used 257 Roberts (58k psi) used 7x57 (56565 psi) cases. There was no redesigning - the cases are equal strength/construction/design just necked down. Don’t take my word for it - obtain some cases and cut them, weigh them, see what others have to say. Weigh the info up, make a decision. Don’t base it on one single example. It is blindingly obvious not all SAAMI and CIP are based 100% on brass strength, but take into account common action and barrel strength and have historical throwbacks. Yes brass was weaker back when 7x57 came out in i think the 1890s. But you’d be crazy to use cases at any pressure that old now if you find could find them due to the brittle aging properties of brass. So it’s a reasonable assumption everyone must be using modern era brass.

It is very very common practice to load old style cartridges to slightly higher pressure (nothing willi nilli here - people dont randomly pick a number they work up using methodical practice and good old common sense) using modern rifles and modern brass than the antiquated limits suggest. It’s not my fault or my idea people do this, it’s just a fact. Yes there are accidents but I’d be willing to bet it’s not normally the experienced handloader who’s carefully working up a ladder in small increments with a chrony with previous data while watching for pressure signs.

I asked if you would be on exceeding the SAAMI pressure limit for 45-70 (28000 psi) when loading for a Ruger no1? It’s well published in most reloading manuals that it’s ok, but it’s exceeding the absolutely-unbreakable-under-any-circumstances-holy-pressure-limit! It seems even the widespread reloading industry take SAAMI limits with a pinch of salt in some cases

 

[Scipio]

so a few questions seems to have arisen, but mainly:

- why are/were these pressure limits originally imposed, and why wernt they changed as actions and brass grew better ?

as seen above, there is some discussion as to wether the (potential limits) of modern brass for these cartridges really is a valid reason to limit the pressure to the listed sami and cip limits, or not.

 

[User00040]

Paralysis by analysis.

Look at the age of some cartridges and the rifles designed to fire them originally. Most of the 'famous' hunting chamberings originate around 1890-1910 from military applications, think 6.5x55, 7x57, 30-06 etc.

The much famed Mauser military design had a third locking lug behind the bolt which was meant as a failsafe, not supposed to be pressure bearing.

After the two world wars, look we have more military rifles than we know what to do with, the Mauser CRF action is great, let's sporterise them!

It was soon found out who cut corners with their steel and proofing as some actions were bearing on this third lug.

A manufacturer who produces ammunition or components for reloading has no way to check your rifle's integrity. Some may carry general warnings such as 'only use in rifles proofed to XX pressure' but who reads that?

A manufacturer such as Federal has to bear in mind that their 30-06 hunting loads might be used in the latest sporting rifles or Grandaddy's WWI Springfield ...

Same goes for 'European' cartridges.

 

[User00040]

as seen above, there is some discussion as to wether the (potential limits) of modern brass for these cartridges really is a valid reason to limit the pressure to the listed sami and cip limits, or not.

Lapua are generally considered to be the best commercially available cases: Lapua Cases | Lapua Brass | Reloading Brass - Lapua

They make cases in 30-06, 6.5X55 etc.

If you buy it and then call them to complain, 'I heard your cases are the best in the world, but why did they burst and ruin my vintage rifle when I am chasing 300WM velocity with the 30-06 or 6.5 PRC velocity with the 6.5x55?!'

I bet they will either put the phone down and block the number or put you on speakerphone to hear the whole office laughing!

Lapua now make 300WM and 6.5 PRC brass, perhaps they became tired of receiving such calls?

 

[Scipio]

hey caberslash exactly, and in those cases such pressure limits did indeed make sense.

But do they make sense in modern rifle and action, which is also available in 65k psi calibers, and where the rounds are loaded in modern brass?
This is where the discussion seem to be at, at the moment, and where edi and harrygrey seems to have their difference of opinions

 

[Scipio]

Lapua are generally considered to be the best commercially available cases: Lapua Cases | Lapua Brass | Reloading Brass - Lapua

They make cases in 30-06, 6.5X55 etc.

If you buy it and then call them to complain, 'I heard your cases are the best in the world, but why did they burst and ruin my vintage rifle when I am chasing 300WM velocity with the 30-06 or 6.5 PRC velocity with the 6.5x55?!'

I bet they will either put the phone down and block the number or put you on speakerphone to hear the whole office laughing!

Lapua now make 300WM and 6.5 PRC brass, perhaps they became tired of receiving such calls?

Haha,
well, as opposed to chasing 300 wm velocities with a 30-06 or prc, i think the original thought was more if reloaders using modern actions of quality and modern brass can not safely, (being carefull and starting low), load a x57, or another older european smokeledss powder cartridge of this era, to pressures also used in other not much younger catridges, like the 30-06 or 270?

Or if there is actually any current material founded reason to avoid this, like the brass not being adapt for it? This is where Edi and Harrygrey seem to disagree

Another reason for this subject and thread was to allow the 7x68 s thread to return to it's original subject

 

[norcan]

Also considering 6,5x55 is a competition round in Scandinavia, so Lapua, Norma, etc etc are making them to withstand more then enough pressure.
More then what CIP is claiming.

 

[User00040]

Or if there is actually any current material founded reason to avoid this, like the brass not being adapt for it? This is where Edi and Harrygrey seem to disagree

Edi is an engineer and has a background working as an OEM, both for rifle stocks and other things.

Someone on here asked about what powerwasher to get, and Edi was able to recommend against using a certain brand/make as it was only manufactured to last a few thousand hours with no spare parts available or repair not possible.

There is a manufacturing standard/tolerance for everything, exceed it and you are in 'at your own risk' territory.

If you look at how the brass will expand and contract to the chamber with each firing, and the variable skill of the reloader in maintaining the condition of the case, determining when it should be binned for safety considerations, I'd always err on the side of caution, and not cry or search for hours if I lose one or two of the >£1+ fancy cases in the long grass...

Most of the questions you ask here are addressed by this book: Muir's book reccomendation

Find a copy and read it

 

[ejg]

The only official set of rules we have in Europe is CIP, rifles and cartridges are made to these rules. Some reloading manuals warn about these pressure limits to be used in older rifles. Often stating to reduce loads by x from their published data if using in older rifles. It does not say increase by x if using in newer rifles.
Now if we increase the loads over say reloading manuals then we run this on assumptions, nothing else. We assume the brass is as strong and the pressure curve similar to another cartridge that was made to a different set of rules.
Of course this is only the start, so many other variables. For example non CIP barrels as in tight bore palma even made by Lothar Walther. Or a home designed Wildcat. In Germany these can be proofed as well however they will stamp your safe load data into the barrel and you should by right not exceed that. I presume that would happen if you bring a 7x68(s) to a German proof house. I don't know how UK proof houses deal with it.

So what do we want to tell other reloaders? Why would we even want to suggest others to run pressures above book value?

Northman 83, to what pressures are these competition cases from Lapua/Norma rated? Is that documented somewhere or is it again an assumption? Is it not just the standard CIP rules apply for the Swede/Skan? Btw the ruptured case in the 6.5x55 we had here was a Lapua case. Will Lapua or Norma back you up in court when something went bang.
Maybe a bit like speed ratings on a car tire. Will probably take a certain amount over the rating however you are on your own if it doesn't hold.

Many issues are avoidable, run a cartridge as it is supposed to be in the rifle you have. If that is not good enough, choose a different cartridge/rifle simple.

edi

 

[Scipio]

That is a fair legal and safety based point to make Edi.

I'd add to that the question if the probably limited fps gain one would get going to those higher pressures is worth it. Because they'd come at the cost of increased recoil, powder use and, as you say, increased (potential) legal and safety risk. Well, the latter being the currrent point of discussion here.

However i am not sure Harry would actually disagree with most of that, and I think his point is a bit different to yours. As i understand it, he is saying that in principle, with some brass at least, there is no mechanical/physical reason as to why one should not be able to load to say 30-06 pressure in a 7x57 , if your action is capable of it too.
You're argument as to the risk of getting that wrong making it an unwise course to follow non the less is a different take on it, albeit also still a very valid one.

Personally i have seen this topic raised several times in the past, all without many clear and trustworthy conclusions being drawn from it. Tbh one might have to talk to a pro arms proofer or a brass/arms manufactorer with a rich and current insight into modern brass production in different calibers to really get to bottom of this.
But a SD member, or even someone just googling this topic, might in future stumble upon this thread, and in that case that person will hopefully have had some food for thought before deciding to do one thing, or the other. So i'd hope at least.

Claus

 

[Scipio]

Edi is an engineer and has a background working as an OEM, both for rifle stocks and other things.

Someone on here asked about what powerwasher to get, and Edi was able to recommend against using a certain brand/make as it was only manufactured to last a few thousand hours with no spare parts available or repair not possible.

There is a manufacturing standard/tolerance for everything, exceed it and you are in 'at your own risk' territory.

If you look at how the brass will expand and contract to the chamber with each firing, and the variable skill of the reloader in maintaining the condition of the case, determining when it should be binned for safety considerations, I'd always err on the side of caution, and not cry or search for hours if I lose one or two of the >£1+ fancy cases in the long grass...

Most of the questions you ask here are addressed by this book: Muir's book reccomendation

Find a copy and read it

haha, hey caberslash, oh dear, another book to read! i do like reading, but it seems to me i'll soon have to expand my library to fit in all of these different new books on ballistics and reloading.
This said, if it is muir who has the book, and he also has that interesting (but not yet shooting) cool sister in law, perhaps i could work out some sort of "two birds with one stone" solution here .... haha ,D

 

[Muir]

So here is another practical side:
People generally don't care much about older rounds. I mean, I there probably isn't a clamoring for 7x68 and other vintage cartridges. With the liability issues of upping their pressure limits aside, look at the financial aspect. They would need to retest all these rounds. They would need to market them judiciously, specifying that these rounds are not to be used in X style of weapons, print data. Print new boxes and labels.... Deal with confused customers and retailers.

It would be a serious expense and all to please (appease) whom? Like everything in the shooting industry, won't happen unless the market drives it. ~Muir

 

[HandB]

Some of the old Mauser military loads for the 7x57 were actually fairly potent. For example: "In 1913, following the lead of French and German Army commands in developing the spitzer or pointed-tip bullet shape, the Spanish ordnance authorities issued a redesigned 7×57mm cartridge with a spitzer bullet (7 mm Cartucho para Mauser Tipo S).[20] It was loaded with a 9-gram (138.9 gr) spitzer bullet fired at a muzzle velocity of 850 m/s (2,789 ft/s) with 3,251 J (2,398 ft⋅lbf) muzzle energy from a 589 mm (23.2 in) long barrel."

I load my 1955 BSA 7x57 with 139gr Hornady SSTs to only slightly higher performance than this with modern powder (50 grains of RS62 generating about 2,900fps) and it works fine with no pressure signs.

 

[Scipio]

Hey Muir, yep, good post, and perhaps also a good part of the reason why Winchester made the 6.8 western, instead of just changing the twist rate of the new 270 rifles to stabilize longer bullets.
There was simply more reason for them not to.

 

[Scipio]

Some of the old Mauser military loads for the 7x57 were actually fairly potent. For example: "In 1913, following the lead of French and German Army commands in developing the spitzer or pointed-tip bullet shape, the Spanish ordnance authorities issued a redesigned 7×57mm cartridge with a spitzer bullet (7 mm Cartucho para Mauser Tipo S).[20] It was loaded with a 9-gram (138.9 gr) spitzer bullet fired at a muzzle velocity of 850 m/s (2,789 ft/s) with 3,251 J (2,398 ft⋅lbf) muzzle energy from a 589 mm (23.2 in) long barrel."

I load my 1955 BSA 7x57 with 139gr Hornady SSTs to only slightly higher performance than this with modern powder (50 grains of RS62 generating about 2,900fps) and it works fine with no pressure signs.

hey HandB
And thank you for sharing this 7x57 insight, as i too shoot this caliber.

There is an Ozz mountain hunter called Scott Tulloch who also shoots an older BSA in 7x57. Have you heard of him? He too also seems to obtain great accuracy and efficiency with that combination.
Anyways he is on YT and can be seen reloading here: .
The video shows him using 47 grn of AR 2209 behind 162 grn amax bullets. But He also clearly states under the video that he is execeeding the reloading manuals reccomended pressures.
Going by his videos the old little 7 in an "old" bsa wood stocked rifle seems to be doing pretty well up in the NZ mountains! ,-)

 

[enfieldspares]

Much time, effort and money was spent in perfecting these "military calibres" at the very end of the 19th Century when France stunned the world with its then revolutionary Balle D rifle cartridge. We, the Brits, got our literal baptism of fire as to the effectiveness of "modern" military cartridges in the Boer War and the Americans in the Spanish American War. Both being on the receiving end of Mr Mauser's design. Later when Germany in 1903 adopted a 154 grain bullet at near 3,000 fps again everybody was astounded...thus the very short lived .30-03 US Government. So everybody wanted the acme in killing at distance a quarry weighing from 10 stones up to 20 stones. For us as sporting shooters that's good too for use on deer. So all this was done in rifles designed in the 19th Century mostly built in the first fifty years of the 20th Century. For use in all climates from the cold of Northern Europe to the heat of Equatorial Africa. These cartridges worked then. They work now. And we have the benefit of being able to improve them further for use on live quarry in the 10 stone to 20 stone weight range by the simple means of using soft point or expanding point bullets. There is little point IMHO in trying to seek to better perfection and when it at the cost of extremes of pressure then this mythical "best" is merely just an enemy of what is already the good..

 

[HandB]

hey HandB
And thank you for sharing this 7x57 insight, as i too shoot this caliber.

There is an Ozz mountain hunter called Scott Tulloch who also shoots an older BSA in 7x57. Have you heard of him? He too also seems to obtain great accuracy and efficiency with that combination.
Anyways he is on YT and can be seen reloading here: .
The video shows him using 47 grn of AR 2209 behind 162 grn amax bullets. But He also clearly states under the video that he is execeeding the reloading manuals reccomended pressures.
Going by his videos the old little 7 in an "old" bsa wood stocked rifle seems to be doing pretty well up in the NZ mountains! ,-)

Neat video. I don't even bother trickling powder - I just use a battered old RCBS uniflow dispenser as it is much quicker. In my experience powder loads are the least finicky aspect of reloading. A few granules more or less seems to make no difference on the grouping.

 

[Scipio]

Neat video. I don't even bother trickling powder - I just use a battered old RCBS uniflow dispenser as it is much quicker. In my experience powder loads are the least finicky aspect of reloading. A few granules more or less seems to make no difference on the grouping.

Hey HandB

Yeah, i hear you, but i suspect that Scott has a pretty minmalistic approach to reloading, and doesnt reload enough to warrant adding more equipment
As for his rifle and (hot) 7x57 load , he has some pretty cool videos of them in action too. NZ mountain hunting looks amazing, and who knew that you dont necessarily need a cartridge made inside the last decade and a 300 dollar Blaser R8 to get things done accurately and effeciently ,D

PS. If you do not already know him, John Barsness is an american gunwriter, who has also written quite a bit on using the 7x57 as a modern cartridge load wise.
I think he is also known as mule deer on the 24hrs campsite hunting forum.

 

[Scipio]

*make that a 3000 dollar blaser. For 300 even i might consider buying one

 

[Andy seatrout]

I’ve been home loading 6.5x55 since last summer, sticking to the reloading data with RS60 powder. Using Hornady Superformance SST 140g as a benchmark (2653fps, 2200fps energy with SD of 13.5) but with 1-2 grains less than maximum stated with the same bullet I was putting out 2789fps SD 20...... with the copper Hornady GMX 120g 2874fps with 2220fp and 21.8 SD......

Looking at the ‘fast for copper’ I pushed up to 3273fps with 120g GMX ( this is in a Sako 85) 2700+ in energy - felt recoil was increased, pressure sign on the case, primer not flattened but ‘smile’ on face, bolt opened fine....but I don’t feel like paying for a new barrel or losing my fingers, and the accuracy was not so good at this speed/ pressure.....so I’ll come down from that..... my firing range with bench etc is only 100 yards from my pheasant pen- so load development was paused in October and will resume in feb.

Looking at it generally I can’t see why I can be shooting a 2750fps 140g lead bullet producing 2200 fp in energy and as a non lead alternative a copper GMX going just around 2900fps 120g producing near enough 2200 fp again. If I look at some of the reloading data it’s obvious that modern actions can take a bit more, some of the Swedish load data is pretty ‘tame’ for reasons of old actions on old rifles - look to European data and pick the SCAN page.

But how much is enough? I don’t intend to shoot deer at long range at all (120 yards personal limit) in common with many of the comments on here, If you want more or faster buy a bigger more modern caliber.....