[Andy Saunders]

When you describe it as "rimless" I wonder if you are describing the inner case or cylinder which slides into the parachute flare cartridge? (Falschirmleuchtpatrone) It will have a hole at its base - from memory with a brass or copper inserted ring. It is (just) slightly smaller in diameter than the actual cartridge to enable it to slide inside and shorter than the overall length. It will have no markings. Also, there were two lengths of flare pistol cartridge. I don't have my examples to hand to measure, unfortunately.