Re the conversion of bars/kg readings to psi: per the above, it gets somewhat complicated if the bars/kg are measured via the crusher system. You can't multiply by 14.5, which works if we're talking bars measured via piezo. Per the Birmingham Proofhouse, a gun with an 850 bar proof (which is a crusher measurement) has a service pressure (piezo) of 10,730 psi, which is slightly less than our American SAAMI standard of 11,500 psi for 12ga guns. 900 bar/kg crusher would thus indicate a service pressure essentially identical to our SAAMI standard.
