referring to fig1 a perspective drawing is shown to a conformal insert 2 that can be constructed to a variety of shapes and that can be secured to a firearm lock assembly 4 . the insert 2 is particularly adapted to securely restrain a firearm to the lock assembly 4 at a vehicle mounted firearm support . the firearm support can be secured to the vehicle ceiling , a divider cage / window , a roll bar . the lock assembly 4 and one or more cradles contain the firearm to the support . the construction and shape of the insert 2 can be adapted to a variety of firearms and prevent marring the firearm . a variety of support cushions or elastomer inserts 2 of tailored shapes that are compatible with the surface contours of a number of firearms used by the law enforcement community are described below . the lock assembly 4 includes a cast base or body 6 and a clamp or latch arm 8 . the clamp arm 8 is secured to pivot relative to the body 6 at a hinge pin 10 that mounts in aligned piano hinge pieces 12 and 14 that extend from the arm 8 and hinge pieces 16 and 18 that extend from the body 6 . a spring 20 biases the latch arm 8 to a locked position . a mounting plate 22 and rail 24 can be secured to the lock 4 with a variety of fasteners ( not shown ) at through holes 26 . the plate 22 and rail 24 , in turn , can be secured to the support framework of a firearm support and / or directly to the vehicle . a keyed tumbler is included with the lock assembly 4 that cooperates with the hinge pin 10 to secure the arm 8 in its latched condition when rotated into contact with the body 6 . a remote switch ( not shown ) is also coupled to the lock 4 via conductors 28 to operate the latch arm 8 . the insert 2 is constructed of a molded elastomer that defines a recess 30 between a pair of vertical arms 32 and 34 and a base 36 . the insert 2 can be molded from a variety of materials , including foams , polymers , rubber and materials containing fillers , and composites to any desired durometer . the insert 2 can also be molded with regions of differing durometer , for example , the arms 32 and 34 can be softer than the base 36 . the surface contour of the recess 30 can be formed to provide any desired support characteristic . the insert 2 fastens to the lock assembly 4 with a number of studs 38 that are shown at fig2 - 4 . the studs 38 mount in holes 40 that are displaced from the fastener holes 26 . the studs 38 are molded slightly oversized from the holes 40 . once mounted , the studs 38 expand and securely retain the insert 2 to the lock 4 . fig5 and 6 show another insert 42 that includes the studs 38 and a pair of flanged prongs 44 . the prongs 44 mount in the counter bored fastener holes 26 to enhance the retention . the shape , number and placement of the studs and / or prongs 44 can be varied at any insert to achieve a desired retention force . a variety of other interlocking fasteners or fastening mechanisms can also be used , depending upon the available attachment points at the lock assembly . preferably , the prongs or any other fastener sufficiently secures the insert 42 to prevent the insert 42 from dislodging during normal use , yet permits the user to switch or replace the insert 42 to accommodate any desired firearm . in the latter regard , fig7 - 15 show a number of other inserts 50 , 60 , 70 , 80 , 90 , 100 , 110 , 120 and 130 that are constructed to be compatible with a number of firearms that are commonly used by law enforcement personnel . where , too , the insert 2 is shown in a generalized form with a solid base 36 and arms 32 and 34 , the inserts 50 - 130 are constructed to provide a number of parallel webs that project from the walls of a surrounding shell . each web is formed with a contoured recess that is shaped with smooth , ridged and / or arcuate surfaces to accept the firearm . the webs can flex as necessary to facilitate mounting . for example , fig7 shows the insert 50 which has several webs 52 that are each formed with a recess 54 . the webs 52 extend from outer sidewalls 56 and 57 and base 58 . the sidewalls 56 and 57 and base walls define a concave shell having a thickness in the range of { fraction ( 3 / 32 )} to ¼ inch . the collection of recesses 54 is constructed to conform to the fore stock of a remington 870 pump shotgun . the thickness and spacing between the webs 52 can be varied depending upon the material and durometer . presently , a thermoplastic elastomer ( tpe ) material is used that exhibits a durometer in the range of 85 to 95 on the shor “ a ” scale . the webs 52 exhibit a nominal thickness in the range of { fraction ( 1 / 16 )} to ¼ inch and a spacing between webs 52 in the range of ¼ - ⅝ inch . fig8 depicts the insert 60 , which is also constructed with a number of webs 62 , and recesses 64 that accept a remington 870 pump shotgun . the width of the recesses 64 varies between the sidewalls 66 and 67 over the length of the insert 60 . some of the webs 62 only extend partially from the sidewall 66 . fig9 depicts the insert 70 , which is constructed with a number of webs 72 , and low profile recesses 74 that accept an m16 - a1 rifle . the webs 72 extend between the sidewalls 76 and 77 such that only a slight depression is exhibited . fig1 , 11 and 12 depict the inserts 80 , 90 and 100 , which are constructed to respectively support a ruger carbine , an ar15 - a2 and a ruger mini - 14 rifle . the webs 82 , 92 and 102 are formed with appropriately shaped recesses 84 , 94 and 104 . fig1 , 14 and 15 depict the inserts 110 , 120 and 130 , which are constructed to respectively support a colt m4 , several automatic shotguns , and an h & amp ; k mp5 rifle . the webs 112 , 122 and 132 are formed with appropriately shaped recesses 114 , 124 and 134 . the recesses 114 and 134 also include stepped ridges 115 and 135 that define regions of differing levels at the recesses 124 and 134 . while the invention has been described with respect to a number of presently preferred firearm support inserts and considered improvements or alternatives thereto , still other constructions may be suggested to those skilled in the art . that is , the disclosed features of the invention might be combined in different arrangements and with still other features in other lock assemblies . the foregoing description should therefore be construed to include all those embodiments within the spirit and scope of the following claims .