doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Lengthened forcing cones and proof

C.I.P. didn't ask my opinion Bill, but I don't think Federal Premium Wing-Shok High Velocity 20g loads are available in the EU

As you observed, C.I.P. 20g service and proof pressures are higher than 12
http://www.cip-bobp.org/homologation/en/tdcc_public?page=1&cartridge_type_id=7
12g 65mm and 70mm �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; PROOF 930 BAR = 13,489 psi
Both 65 and 70 mm 16g standard is SERVICE 780 BAR or 11,313 psi; PROOF 980 BAR or 14,214 psi.
Both 65 and 70 mm 20g standard is SERVICE 830 BAR or 12,038 psi; PROOF 1040 BAR or 15,084 psi.

And the Hunter Arms "Close Enough for Farm Implements" illustration