http://www.cip-bobp.org/homologation/en/tdcc_public?page=1&cartridge_type_id=7

12g 65mm 70mm = 2 1/2 2 3/4 standard proof lead or steel (limited to no larger than 3.25 mm and max. fps 1,300) transducer psi
Service pressure 740 BAR = 10,733 psi
Maximum statistical individual pressure 850 BAR = 12,328 psi
Standard proof 930 BAR = 13,489 psi

12g 76 mm = 3 lead High performance/superior proof transducer pressure
Service 1050 BAR = 15,229 psi
Maximum statistical individual pressure 1200 BAR = 17,405 psi
Magnum proof 1320 BAR = 19,145 psi

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