larger than the cartridge the adapter is a generally hollow tubular member having a cylindrical tapered outer wall and an inner wall concentric with the outer wall with the inner wall being uniquely tapered to specified degrees depending on the shell gauge to be used application_number US 16691002 A description referring first to fig1 there is shown the adapter of this invention generally designated by the numeral 1 the adapter 1 is a generally cylindrical in configuration comprising outer wall 3 and inner wall 5 shown in dotted line which is of slightly less diameter than the outside diameter of the adapter the adapter 1 has opposed open ends 7 and 9 for insertion therethrough of a shotgun shell cartridge 11 shown below the adapter 1 the shotgun shell 11 is also cylindrical in configuration with an outside diameter slightly less than the inside diameter of the adapter in order to fit snugly therein the shotgun shell 11 has a closed locked end 13 and a crimped forward end 15 for easy insertion of the shotgun shell through the adapter for optimum shooting patterns from a shotgun incorporating the adapter of this invention the adapter must have certain design and dimensions which are of paramount consideration the significance of these features will become apparent from the ensuing description thus the inner and outer walls of the adapter must be tapered slightly such that the outer walls are tapered inward while the inner walls are tapered correspondingly outward as shown in fig1 thus the relative dimensions and degree of taper of the walls of the adapter are paramount to the efficacy of the adapter when used to.