I picked up a Haenel 303-Super at Melbourne last weekend and so far I'm quite liking working on.
Started stripping it today as I was told it had been sat in a cupboard for quite a few years, and found a load of shrapnel embedded in the piston seal





My current best guess is someone put ball bearings down the barrel to try to shoot them out.... Then they fell through the transfer port into the main chamber......

Also, any tips on removing scratches from the inside of the compression chamber?