What Larry said, but it doesn't need to be confusing.
The Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives standard is to report velocity at 2.5 meters = 8.2 feet from the muzzle.
https://www.cip-bobp.org/en/cip

Velocity at the SAAMI standard of 3 feet is about 70 fps less than the muzzle.

Apparently if British shells are for domestic use, the domestic maker can use British standards. Maybe a British correspondent could confirm.
If for export (clearly applicable to the current Italian and Spanish products) the shot size and speed is reported in "American"

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