Certainly every British gun and imported gun without a recognised Proof House goes through Proof at either London or Birmingham before it can be sold. I understand that some Continental guns are just 'Batch Tested'. Certainly a Gunsmith, who I know well, had a Spanish gun by a well known Maker in with Proof Marks but the chamber rim recess wasn't cut so could not have been Proof tested as a cartridge could not be inserted. Lagopus…..