reference now will be made in detail to the embodiments of the invention , one or more examples of which are set forth in the drawings . each example is provided by way of explanation of the invention , and not meant as a limitation of the invention . for example , features illustrated or described as part of one embodiment may be used with another embodiment to yield still a further embodiment . in fact , it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention . referring to fig1 an exemplary embodiment of a fishing lure body 10 according to the present invention is illustrated . the lure body 10 includes a hull 12 configured in the overall shape of the lure . it should be appreciated that the size and shape of the hull 12 may be configured in various combinations depending on the particular type of lure body 10 desired . in the illustrated embodiment , hull 12 has a generally streamlined configuration and includes a head section 14 , a middle section 16 , and a tail section 18 . while any suitable material may be used for construction of hull 12 , wood or plastic are preferred because these materials can be readily shaped and decorated as desired . the hull 12 includes any number or combination of ornamental features intended to provide the lure body 10 with a more realistic and life - like appearance . for example , the hull 12 may be provided with scales , gills , fins , eyes , or other characteristics . examplary hull 12 includes ornamental features such as scales 20 and eye 22 . a diving plane 24 is located near the head section 14 of hull 12 . as the lure is being retrieved through the water , diving plane 24 drives the lure body 10 to a certain depth within the water . the depth to which the lure body 10 will travel is dependent upon variables such as the angle of plane 24 and the speed of the retrieve . for this exemplary embodiment of the invention , lure body 10 is equipped with two hook loops 26 for attachment of treble hooks 28 . fig1 is only an example of the number and positioning of loops 26 and hooks 28 . one or any number of various types of hooks may be positioned on lure body 10 as desired . also shown by way of example is line loop 30 for the attachment of fishing line to the lure body 10 . other mechanisms may be used in a variety of configurations and locations on lure 12 for attaching the line . referring now to fig2 a and 2b , lure body 10 is constructed from hull 12 and a cartridge 32 that is inserted into or contained within hull 12 . ( cartridge 32 is shown with phantom lines in fig1 ). cartridge 32 defines an interior channel 34 that is oriented longitudinally along the cartridge 32 of lure body 10 . in the direction moving from the head section 36 to the tail section 38 of cartridge 32 , interior channel 34 includes an incline 40 . for the exemplary embodiment of a lure body 10 being described , interior channel 34 is formed as a single chamber within cartridge 32 . it should be understood , however , that interior channel 34 could be formed from a variety of configurations — including internals walls or other internal structures . a plurality of weights 42 are positioned within interior channel 34 and configured for movement along the interior channel 34 . as shown in the exemplary embodiment of the figures , the weights 42 are cylindrically shaped and can be made to roll or slide along interior channel 34 between the head section 36 and tail section 38 of cartridge 32 when lure body 10 is in use . although four weights 42 are depicted in the figures , any number of weights may used . furthermore , a lure body 10 utilizing only one weight is within the scope of the present invention as set forth in the claims below . as shown in fig2 c , in this particular exemplary embodiment of the invention , the lure body 10 includes a rider or lock mechanism 44 that is configured to move along the interior channel 34 in conjunction with the plurality of weights 42 . the lock mechanism 44 includes pocket 46 and pocket 48 for the receipt of two of the plurality of weights 42 . as the weights 42 move along interior channel 34 , mechanism 44 moves with the plurality of weights by “ riding ” upon the weights in pockets 46 and 48 . while the exemplary embodiment shows mechanism 44 configured for moving with two of the weights 42 , it should be understood that it is within the spirit and scope of the present invention to configure mechanism 44 to move alone or upon one or any number of weights 42 . retractable boss 50 is positioned within lock mechanism 44 . the boss 50 is capable of moving between two positions during operation of the lure body 10 . during casting , the boss 50 is caused to retract within mechanism 44 ( as will be more fully discussed ). the retraction of boss 50 allows the mechanism 44 to move from the head section 36 towards the tail section 38 of cartridge 32 and thereby allows the plurality of weights 42 to so move along the interior channel 34 . during retrieval of the lure body 10 through the water while fishing , boss 50 is caused to extend into a recess 52 along interior channel 34 , as depicted in fig2 c . in this extended position , boss 50 restrains locking mechanism 44 within the head section 36 of cartridge 32 and thereby also causes the plurality of weights 42 to remain in the head section 36 . fig2 a through 2c depict but one exemplary embodiment of a lock mechanism 44 by which the position of the weights 42 can be secured within the lure body 10 , and it should be understood that other embodiments are within the spirit and scope of the present invention . by way of example only , lock mechanism 44 includes any structure configured to move or ride with one or more weights and used to secure the position of the weights . [ 0029 ] fig3 a though 3 c will now be used to more fully describe the operation of this exemplary embodiment of the present invention . just before casting the lure body 10 , an angler will generally position the lure body 10 from the fishing line in a vertical position as shown in fig3 a . the force of the plurality of weights 42 is exerted on lock mechanism 44 which in turn causes retractable boss 50 to move along a ramped wall 54 ( shown in fig2 c ) in recess 52 . the combined effect of the rearward motion of mechanism 44 and ramped wall 54 causes the boss 50 to be moved into its retracted position within mechanism 44 . the plurality of weights 42 is thereby released , moves along interior channel 34 , and comes to rest in the tail section 38 of cartridge 32 . as a result , the center of gravity of lure body 10 is moved toward tail section 18 . during casting , the plurality of weights 42 generally remain in the tail section 38 of cartridge 32 . as the lure body 10 lands and come to rest in the water , the lure body 10 remains in a vertical position ( as shown in fig3 a ) in the water and the plurality of weights 42 therefore also remain in tail section 38 . again , in this position , the center of gravity of lure body 10 remains generally within tail section 18 of lure body 10 . after landing in the water , the angler begins to retrieve the lure body 10 by reeling in fishing line 56 . as the lure body 10 is pulled forward at the point of connection ( loop 30 ) with fishing line 56 , the diving plane 24 drags against the water and causes the lure body 10 to move from the vertical position of fig3 a to the horizontal position shown in fig3 c , with fig3 b showing an intermediate position between those of fig3 a and 3b . as a result , the plurality of weights 42 are caused to slide or roll along interior channel 34 because of the incline 40 . as the plurality of weights 42 reach the head section 36 of cartridge 32 , the boss 50 of lock mechanism 44 falls into recess 52 . boss 50 thereby secures the plurality of weights 42 within the head section 36 of cartridge 32 during the retrieve . as a result , the overall center of gravity of lure body 10 is moved towards the head section 14 of lure body 10 to ensure proper operation and movement of the lure body 10 as it is retrieved through the water by the angler . the above is a description of an exemplary embodiment of the present invention and other embodiments are within the spirit and scope of the invention as claimed below . by way of example only , the exemplary embodiment discussed above used a cartridge 32 that was placed within a hull 12 to create the overall lure body 10 . however , it should be understood that lure body 10 could be constructed as a single piece or unit with also providing the overall shape and outward appearance of lure body 10 . also , using the teachings disclosed herein , one of skill in the art will recognize that various other mechanisms that are within the scope of the following claims can be used to control the position of the weight ( s ) within the lure body . therefore , it should be appreciated by those skilled in the art that modifications and variations can be made to the lure as described herein , without departing from the scope and spirit of the claims . it is intended that the invention include such modifications and variations as come within the scope of the appended claims and their equivalents .