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"BTW, the CIP max pressures of European metric cartridges were never based on destruction tests."

Nor are the SAAMI specs.

The secs noted are maximum working average pressures for the normal actions used in these rounds - not destructive pressures. I do know know why you brought that up?

I should not have said that I did not understand how the smaller case could be loaded at higher speeds than the smaller case. I do understand that if one loading company is restricted to powders that do not develop the ballistics that another company can produce with it's powders, the ballistics of the first company could be inferior. Another reason, of course is that either company might not load the round to it's potential - thus shifting ballistics around.

As to pressures, the pezio measuring system now being used more and more, is repeatable and more accurate than the CUP ie: crusher/micrometer measuring system of old.

I am aware that some rounds were developed before or around the turn of the century & with grossly outdated and sometimes 'flighty' powders. Loads were kept purposely low to be safe in hot climates, or simply to keep flighty tendencies in check. No single individual hunters back then loaded with those 'new' smokeless powders as they lacked the expertise and knowledge to do so safely- or were restricted from loading by their governments.

Many of those 'early' rounds have the same ballistics today as when they were developed. Some have been updated by companies such as Norma, DWM and RWS.

If the 6.5x57 is still being loaded to it's 'early development' era ballistics, so be it. That's the way it is.

Someone chambering that round here in the free-to-handload part of the world, would probably never shoot a factory round, but merely handload all his or her ammo to it's potential and would not restricted to outdated loadings.

I was merely looking at the situation and seeing that due to their listed working pressures, even by Euro specs, that the 57m case should be far ahead of the smaller capacity 54mm case.

If the 6.5x57 isn't loaded to it's current printed specs as listed in the charts, well, that's merely the choice of whomever is loading the ammo & Eupoeans are stuck with those loads. That is similar to how Norma still loads the excellent 9.3x57 as if it was 1925.

Those same model 46's Husqvarna's are also chambered for the 6.5x55, 8x54, 8x57, 9.3x62 and we've 30/06's trunign up in the same commercial model 96 actioned Husky's. None of these rounds are held to Norma's guess at working pressures for the 9.3x57, ie: 34,000 copper crusher units of measure.

This is one of the major reasons we handload and tend to look at all rounds from a handloading standpoint, not from the ballistics available on the market.

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Daryl

"a gun without hammers is like a Spaniel without ears" King George V

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