CIP 12g 76 mm = 3 LEAD High performance/Superior Proof
Service 1050 BAR = 15,229 psi
Maximum statistical individual pressure 1200 BAR = 17,405 psi
Magnum proof 1320 BAR = 19,145 psi
12g STEEL regulations: the barrels should carry the High Performance Steel Fleur de Lys stamp and be marked Steel Shot
http://www.chircuprodimpex.ro/produse/al...-ammunition.pdf

Italy is a member of CIP, but according to Gerhard Wirnsberger, The Standard Directory of Proof Marks in 1962 established Standard Proof at 12,801 psi (probably by LUP/crushers) indicated by a star over PSF AND Superior Proof at 17,637 psi, with 2 stars over PSF marks.
Superior Proof is mandatory for chambers longer than 70mm = 2 3/4.
FABARM voluntarily proof tests to 1630 BAR = 23,641 psi
http://www.fabarm.com/web_eng/caratteristiche-dettaglio-1630.asp

Great Britain adopted the 1969 Commission Internationale Permanente pour l'Epreuve des Armes Feu Portatives standards March 1, 1980.

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