Question re Pressure with the 6.5x55 SE

[South Pender]

I'm having some difficulty in understanding the maximum pressure standard from the European CIP for the 6.5x55, which is given as 55,114 piezo PSI for modern firearms, and is even lower--51,000 piezo PSI--from SAAMI.

What makes this hard to understand is that the European CIP gives 60,191 PSI for the .260 Rem. and 63,091 PSI for the 6.5 Creedmoor. I could understand the lower pressure standard for the 6.5 Swede if it were to apply to all 6.5 Swedes, including the older military rifles, but it is stated as applying to modern firearms. Why should we hold the 6.5x55 pressures down to this lower level in a modern action like a Remington 700, when we can go so much higher with a .260 Rem. or 6.5 CM?

Anyone with some insights on this?

 

[DocBII]

South Pender,

Since I'm using modern actions and barrels in my 6.5x55s, I use a 60 kpsi limit in QL for developing my loads. I don't usually go near that limit, since i can reach speed and accuracy/precision goals at lower pressures.

You can do what you wish since you aren't in Europe, and if you don't plan on shooting high pressure ammo in older actions.

HTH,
DocBII

 

[South Pender]

DocBll, that makes sense. I too have used 60K PSI in my load development work with QuickLoad. The program defaults to the CIP maximum of 55,114 PSI for the Swede, but it's easy to override that.

It just seemed strange. If you have a 6.5x55 barrel on your Husqvarna, Sako, or Remington action, you should hold pressures down to 55,114 PSI, but once you take that barrel off and screw a 6.5 CM barrel into the same action, you're good to go to 63,091 PSI!

 

[Infrequent Shooter]

Fellow shooting compressed load of H1000 at 1000 yards. Milk Jug challenge. modern action. 3000fps. I am sure it is fairly high pressure. Guy has it together. Repeat, his is a modern action. Youtube. good viewing. MAKE SURE YOUR ACTION IS MODERN!! STUDY YOUR LOAD. WORK UP POWDER LEVELS.

 

[Infrequent Shooter]

I'm having some difficulty in understanding the maximum pressure standard from the European CIP for the 6.5x55, which is given as 55,114 piezo PSI for modern firearms, and is even lower--51,000 piezo PSI--from SAAMI.

What makes this hard to understand is that the European CIP gives 60,191 PSI for the .260 Rem. and 63,091 PSI for the 6.5 Creedmoor. I could understand the lower pressure standard for the 6.5 Swede if it were to apply to all 6.5 Swedes, including the older military rifles, but it is stated as applying to modern firearms. Why should we hold the 6.5x55 pressures down to this lower level in a modern action like a Remington 700, when we can go so much higher with a .260 Rem. or 6.5 CM?

Anyone with some insights on this?

Liability fears.

 

[ebb]

Every cartridge you mention has different brass, is the 6.5-55 brass capable of the same pressure as 260 rem and 6.5 creedmoor? I am sure I don't know, do you? Or maybe it is liability fears, or some other factor that samii knows about and we don't.

 

[mikecr]

I could be wrong, but I suspect it's not about the action so much as the chamber.
If it's a sloppy chamber,, big clearances, that could lead to more brass yielding and bolt thrust for a given pressure.

 

[David Milisock]

I'm having some difficulty in understanding the maximum pressure standard from the European CIP for the 6.5x55, which is given as 55,114 piezo PSI for modern firearms, and is even lower--51,000 piezo PSI--from SAAMI.

What makes this hard to understand is that the European CIP gives 60,191 PSI for the .260 Rem. and 63,091 PSI for the 6.5 Creedmoor. I could understand the lower pressure standard for the 6.5 Swede if it were to apply to all 6.5 Swedes, including the older military rifles, but it is stated as applying to modern firearms. Why should we hold the 6.5x55 pressures down to this lower level in a modern action like a Remington 700, when we can go so much higher with a .260 Rem. or 6.5 CM?

Anyone with some insights on this?

You don't have to hold it down if you're using a modern firearm bolt action or even a Mauser 98, Springfield or other manufacturers 03 or 03-A3. I believe you're OK with Model 17 action also.

The lower pressure listing for the 6.5 x 55 is because the Model 96 Mauser was proof tested lower, I believe around 66,132 PSI.

 

[JSH]

You don't have to hold it down if you're using a modern firearm bolt action or even a Mauser 98, Springfield or other manufacturers 03 or 03-A3. I believe you're OK with Model 17 action also.

The lower pressure listing for the 6.5 x 55 is because the Model 96 Mauser was proof tested lower, I believe around 66,132 PSI.

Yup it’s pressure I am pretty sure.
And before anyone jumps on the wagon about unsafe, there are numerous load levels for 45-70, as well as 45 Colt. I have done the same with the 32-20 with zero issues in a Blackhawk, makes the 327 look pretty anemic.

 

[DGP4]

Even a small ring Mauser can handle 60-65K pressure. Ammo manufacturers just don't want to run the risk of liability.

 

[David Milisock]

Even a small ring Mauser can handle 60-65K pressure. Ammo manufacturers just don't want to run the risk of liability.

There has to be a standard so manufacturers know how manufacture safe ammunition. If you reload make sure to stay within the safe limits of the action, if you're working with a used action take appropriate steps to know the chamber dimensions and the bore.

It's not rocket science I had a custom 450 Marlin built on a 98 Mauser to shoot 500 grain projectiles, I load it to 60,000 PSI, way over the lever gun loads.

I know people doing similar things with Enfield and Siamese Mauser actions and 45-70 cases. Some say cases have shorter lives others claim not.

 

[SKWERLZ]

I'm having some difficulty in understanding the maximum pressure standard from the European CIP for the 6.5x55, which is given as 55,114 piezo PSI for modern firearms, and is even lower--51,000 piezo PSI--from SAAMI.

What makes this hard to understand is that the European CIP gives 60,191 PSI for the .260 Rem. and 63,091 PSI for the 6.5 Creedmoor. I could understand the lower pressure standard for the 6.5 Swede if it were to apply to all 6.5 Swedes, including the older military rifles, but it is stated as applying to modern firearms. Why should we hold the 6.5x55 pressures down to this lower level in a modern action like a Remington 700, when we can go so much higher with a .260 Rem. or 6.5 CM?

Anyone with some insights on this?

It’s a similar situation with the 45-70 cartridge, in modern and stronger actions you can up the spice level considerably and you can get loaded ammunition that absolutely should not be used in older BP 45-70’s.

Lapua 6.5x55 brass will easily handle even magnum levels of pressure in a solid action.
Load appropriately.

 

[Blobby159]

Liability fears.

Indeed, probably spot on!
I have been loading my 6.5x55 SE Tikka t3 heavy barrel for the last five to six years. As I have no means at home to test my loads Pressure Values I scrutinise the fired brass and primers whilst taking note of the projectile velocities (I do have a Chronograph that I use always whilst I am testing accuracies of my new loads) and I pay close attention to the way my rifle handles following the firing of each round, particularly noting how the bolt opens after each firing!

I allow these together to influence how much powder I load of any particular type, having first started any test series with the powder load weights WITHIN advised limits as specified in the powder manufacturers reloading manuals…

With this in mind and my progress noted on paper - carefully - such that I have a written record of all I do, I load either till I get (or perhaps DON’T get) an accurate and repeatable load OR till those mentioned signs tell me I am stepping close to possible high and/or unwise pressures in my loads, at which times I STOP THERE!!

As a general note I have found from my load data for any specific bullet powered by a particular make/model and number of Propellant powder is virtually ALWAYS HIGHER by around 100fps or so +/- about a further 50fps depending b those velocities advertised in load tables for the 6.5 Creedmoor …. It can even be slightly greater yet when the bullet weights driven by these two cartridges gets higher - above tge 139/140gr region and when I have chosen really quite slow propellants like ‘Reloader 26’.

This also applied/applies very readily to the 260Rem when compared to my Reloads of the same bullets in the 6.5x55 Swedish when the latter was/is being constructed in strong, modern brass like Lapua and Nosler, and when shot from modern, strongly constructed rifles such as Tikka t3 and Remington 700 rifles and the like.

These are MY findings anyway, and my findings appear to be agreed to in much of the recent load literature I have read. However, one needs to adopt one’s own recognised and assured Safe Practices where bullet reloading is concerned as it is undoubtedly a dangerous hobby and pursuit that requires Safety to be Paramount …..