I recently obtained the cartridge pictured below and in the attachments. Four or five showed up in an old collection, all identical. The overall weight is 183,8gr and the identical round with a normal case weighs 182.2. My initial suspicion is that this is a proof round, but that was only a guess.
I also have another round that came out of an old collection in North Germany in 2009. The overall weight on this round is 176.7gr and the ball round with the identical headstamp weighs 177gr. This difference seems to be in the wrong direction for the red to indicate a proof round. In addition, on http://www.amkat.se/ ythe author show a 1982 proof with a black base.
I would greatly appreciate thought on these two rounds or other information.