Device for firing a diabolo form bullet from a firearm

Device for firing a diabolo form bullet from a firearm with a rifled barrel, wherein said device consists of a cartridge comprising a housing, a detonation cap connected to one end of the housing in a gas-tight manner, said detonation cap containing a gas-forming propellant means, said gas-forming propellant means providing the sole source of gas in said cartridge on ignition of the gas-forming propellant means, said housing having an expansion compartment for expansion of said gas and said housing having an outer surface tapered toward another end of said housing remote from said detonation cap, said tapered outer surface aligning said diabolo form bullet loaded coaxially in said rifled barrel of said gas pressure operated fire arm by engaging a tapered recess provided in said diabolo form bullet, whereby said diabolo form bullet is forced into said rifled barrel so as to calibrate said diabolo form bullet;

• and a membrane covering said other end of said housing remote from said detonation cap, wherein said housing has at least one breakthrough region, in addition to said membrane, said at least one breakthrough region rupturing when a gas pressure of said gas generated on ignition of the gas-forming propellant means exceeds a predetermined maximum value.