650 BAR = 9427 PSI. If that's LUP then I don't think one needs to worry about shooting US shells in the thing. Of course they may have changed the system of measuring when the BAR's were introduced. I did caution that formula was good only for those old British pressures measured in Tons per Sq In. Note that if you run the formula for 3 tons you get a PSI of 8960 or about 618 BAR. A 3Ľ ton LUP converts to 9800 PSI while a 3˝ ton one goes to 10640. 3 3/4 tons = to 11,480 or about the same as our SAAMI spec. This is getting pretty high. I seriously doubt that any game gun was meant for over 13K PSI for a service load.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra