Some interesting information and comments in this thread.
The original article referenced at the beginning of this thread is nonsense. There is no straight-walled 9mmx19 cartridge and pressure differences are to be expected when 2 organisations are testing using different methods and equipment.
As Rick W noted, I commented a while ago on a thread by member GT who was having problems with a P08 rebarrel job.
My suggestion was to use CIP Standard headspace gauges because they are made to a headspace tolerance of 0.012" whereas the SAAMI type are to a tolerance of 0.022". This difference occurs with most calibres and for that reason I would always recommend that the CIP standard be the first reference where there is a problem or discrepancy.
The CIP is a regulatory authority and the standards published by them have the status of law in the CIP signatory countries. No ammunition may be sold on their commercial markets which does not meet all aspects of the standards and is so marked.
The SAAMI is an association of companies which publishes recommendations for dimensions and pressures of ammunition. Compliance with the SAAMI standards is entirely optional in the US (and NZ), even for companies who are members of SAAMI. Also there is no requirement to identify which ammunition does or does not comply with the SAAMI standards.
As Rick W noted previously, it's really 2 different approaches.
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