My bad on messing up the 1200 mark on the barrel flats. That is indeed the proof pressure. However, that gun is old enough that at the time it was proofed, CIP countries were still using the old crusher method. I have an email from the master of the Birmingham Proofhouse explaining the same mark previously found on magnum/superior proof British shotguns, when they were still using the crusher method of measuring pressure. (The more typical mark seen back then was 850 bar, which was the standard--versus superior or magnum--proof pressure.) From that email for a gun marked 1200 bar: " . . . the transducer values are 1050 bar service and 1370 bar proof." So skeeterbd, that box of Italian shotgun shells marked "1370 bar" are for guns of the same proof as yours--simply measured by the current (electronic transducer) method versus the old lead crusher system. You cannot convert directly to psi from crusher bars, as I did in my earlier post. You'd need to multiply 1370 x 14.5 to get the proof pressure in psi.
Last edited by L. Brown; 01/02/14 12:47 AM.
