RWS produces the 6.5x52r, I would like to hear their take it. As I believe Jani is correct. For years they were considered the same by sportsman...
Proof law applies not only to guns, but to the ammunition as well. With respect to RWS, Norma, S&B, and other European cartridge manufacturers, all that's needed is to look at the CIP specs, posted previously. They're law, not industry standard, and that's the standard that is observed. In CIP countries (much of Europe), ammunition is required by law to be CIP compliant, and the package must be so marked, or it's illegal to sell it. Proof houses are responsible for spot checking compliance. When a lot exceeds CIP MAP, it must be withdrawn and, yes, it happens.
For what you're suggesting to be true, Jani, the proof standards of of one or both of these cartridges would have to have changed somewhere over the years - a lot. That would be unusual in the extreme, as there are fundamental safety reasons to never permit this to happen, and your rifle is a good example of why. Further, such a significant change would be well known.
The crusher pressure standards referred to above are long out of date. CIP standards are PSI, piezo electric transducer, not CUP, and CIP uses their own unique protocol, including a drilled case, which SAAMI has never used. As everyone knows, there's no ready conversion from crusher to transducer. If the standard pressures were allowed to change, that would place previously proven guns out of proof, with no assurance that new ammunition would be safe in them, so the conversion had to be done via testing. Current standards look different, but the pressures haven't changed, they've just been restated using a different measurement method. That keeps weapons in proof, and standard ammunition pressures safe.
