I have two Floberts I’m not sure about. Ones a 6mm the other is a 9mm.
The 6mm has a raised “G” Headstamp (Gevelot). The case is slighlty longer then a typical 6mm Flobert (9.22mm /.363 inches). The bullet is much longer than normal and has an unusual wide shallow groove and held in with a heavy segmented crimp. Total cartridge length of 16.65mm (.656").
The second one is a 9mm Flobert with a raised bird headstamp (Braun and Bloem). It has a much longer and heavier 2 grooved lead bullet than normally used in 9mm Floberts. It was presented to me as a “pistol cartridge”.