Raimey,
I'm always eager to learn of new cartridges.The one I'm speaking of is 6.5x65R or 6.5x65R RWS from 1988-1990.These are based on .468-.473"head dia. case. What is the head size of the 6.5x65R Sauer you are talking about? Another possibility would be 6.5x61R,but it's not too common(6.5x70R is really uncommon). I'm looking forward to the chambercast.
Mike