Abstract:
A firearm sight mount with a sight mount body configured for clamping on the outside of a firearm barrel. In one embodiment the sight mount has a unitary sight mount body that is split to permit the body to be slipped past any existing front sight on the firearm barrel. The split construction of the sight mount body permits it to be clamped to firearm barrels having different outside diameters and tapers. The other embodiments use a two piece body that are configured to be clamped to firearm barrels having different outside diameters and tapers and in one of these embodiments provision is made for the sight mount to fit around a rib on the barrel. In all embodiments, the sight mount body has a flat rectangular shaped mounting surface with short cylindrical projections sized and shaped to mesh with corresponding holes in the sight and hold the sight in place. Two screw holes are also provided in the mounting surface for holding the sight to the mounting surface. The use of only two screws reduces the number of screws that can work loose when the firearm is fired.

Description:
BACKGROUND OF THE INVENTION 
     Telescopes and similar sights have come into widespread use on firearms. These sights are used on many different types of firearms, such as rifles or shotguns and pistols and revolvers. These types of sights are typically secured to the receiver or breech end of the firearm and possibly also the barrel using a mounting assembly or system that usually has threaded screws or bolts. Proper accuracy with such sights requires that the the mounting system remain completely rigid. Unfortunately, when the firearm is fired the recoil tends to loosen the screws and/or bolts that are used to secure the sight to the firearm. This makes it impossible to shoot the firearm accurately since the sight will not remain in one fixed position with respect to the firearm. 
     Another problem associated with the loosening of the screws associated with prior art sight mounts is the possibility that such screws can bend or actually shear so that the sight and the sight mount become totally useless. In addition, the bolt or screw holes can also become distorted and enlarged. Under appropriate circumstances when the sight mount screws or bolts become loose tremendous lever or torque forces can be exerted upon these loose screws or bolts. This is possible since these screws or bolts in many instances have a long length and a force exerted on the end of such a long screw or bolt is equivalent to exerting a force on a long lever arm. consequently, a large torque is exerted upon the screw or bolt that can easily bend or sheer the screw or bolt. 
     A further problem associated with mounts for telescopic and similar type sights is that these mounts are different for each specific firearm. Consequently, it is not possible to use the same mount for different type firearms or to switch a mount from one type firearm to another. In addition, with prior art mounting systems it is necessary for a distributor or a retailer to maintain a wide variety of numerous sight mount components for a wide variety of firearms in order to satisfy their customers. This is both expensive and time consuming. 
     The firearm sight mount of this invention overcomes these problems associated with prior art telescopic and similar sight mounts. This firearm sight mount uses a minimum of screws or bolts and replaces many of the screws with tight fitting short studs that cannot work loose and are not susceptible to damage by high torque forces. The nature of the construction of the firearm sight mount permits it to be secured to the barrel of an unaltered firearm, and it is possible to use this firearm sight mount on a variety of different types of firearms that have basically similar outer barrel dimensions. 
     SUMMARY OF THE INVENTION 
     This invention relates to firearm sights and mounts for small arms and more particularly to a firearm sight mount for the barrel of a firearm. 
     It is an object of the invention to provide a firearm sight mount that is easy to use on a variety of firearms. 
     It is an object of the invention to provide a firearm sight mount that is easy to mount on a firearm barrel that has an existing front sight without removing the existing front sight. 
     It is an object of the invention to provide a firearm sight mount that is easy to mount on a firearm barrel that has an existing front sight without altering the existing front sight. 
     It is an object of the invention to provide a firearm sight mount that is easy to remove from the firearm. 
     It is an object of the invention to provide a firearm sight mount that does not require modification of the firearm for installation. 
     It is an object of the invention to provide a firearm sight mount that does not damage or mar the finish of the firearm on which it is installed. 
     It is an object of the invention to provide a firearm sight mount that does not unbalance the firearm. 
     It is an object of the invention to provide a firearm sight mount that is made from a light weight material. 
     It is an object of the invention to provide a firearm sight mount that is made from plastic. 
     It is an object of the invention to provide a firearm sight mount that is very rugged. 
     It is an object of the invention to provide a firearm sight mount that is easy to manufacture. 
     It is an object of the invention to provide a firearm sight mount that is inexpensive to manufacture. 
     It is an object of the invention to provide a firearm sight mount that is manufactured by molding a plastic material. 
     These and other objects of the firearm firearm sight mount will become apparent from the following described firearm sight mount invention that includes a sight mount body, connecting means on the sight mount body for connecting the firearm sight mount to a firearm barrel and means on the sight mount body for mounting a sight to the sight mount body. The firearm sight mount is either split or formed in two sections to enable the sight mount to be mounted on a barrel that has a sight and possibly a sight rib. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be hereinafter more fully described with reference to the accompanying drawings in which: 
     FIG. 1 is a side elevational view of a rifle illustrating one embodiment of the firearm sight mount invention and a sight attached to the muzzle end portion of the firearm barrel; 
     FIG. 2 is a side elevational view of the firearm sight mount invention attached to the muzzle end portion of the barrel of the firearm set forth in FIG. 1; 
     FIG. 3 is a top plan view of the firearm sight mount set forth in FIG. 2; 
     FIG. 4 is an enlarged end elevational view of the firearm sight mount invention set forth in FIG. 3 with the firearm sight mount invention not attached to the muzzle end portion of the barrel of a firearm; 
     FIG. 5 is a side elevational view of a second embodiment the firearm sight mount invention attached to the muzzle end portion of the barrel of a firearm such as that set forth in FIG. 1; 
     FIG. 6 is a top plan view of the firearm sight mount set forth in FIG. 5; 
     FIG. 7 is an enlarged end elevational view of the firearm sight mount invention set forth in FIG. 6 with the firearm sight mount invention not attached to the muzzle end portion of the barrel of a firearm; 
     FIG. 8 is a side elevational view of a third embodiment the firearm sight mount invention attached to the muzzle end portion of the barrel of a firearm such as that set forth in FIG. 1; and 
     FIG. 9 is an enlarged end elevational view of the firearm sight mount invention set forth in FIG. 8 with the firearm sight mount invention not attached to the muzzle end portion of the barrel of a firearm. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring first to FIG. 1, one embodiment of the firearm sight mount is illustrated and is designated generally by the number  10 . As illustrated, the firearm sight mount  10  is shown attached or mounted on the muzzle end barrel portion  12  of a firearm  14 . The fact that the firearm sight mount  10  is configured to be mounted on the muzzle end barrel portion  12  of the firearm  14  permits it to be used on a variety of firearms since most firearms have their muzzle end barrel portions relatively free of any obstructions such as stocks, bolts and other mechanisms or the like that would interfere with the attachment of the firearm sight mount  10  to the firearm. 
     The firearm sight mount  10  comprises a unitary sight mount body  16  that is made from a plastic material that is strong but will bend or yield to some degree. This sight mount body  16  has a centrally located generally circular cross section shaped aperture  18  that extends through it from its forward surface  20  to its rearward surface  22  along the long central axis A of the sight mount body  16 . The sight mount body  16  has a split  24  in it that extends from the surface of the hole  18  outward to the lower surface  26  of the sight mount body  16 . This split  24  permits the right and left portions  28  and  30  that are located around the hole  18  to be spread apart slightly and indicated by the arrows B and the dashed lines for the spread apart portions  28  and  30 . This permits the hole  18  to change its size and shape to accommodate gun barrels with different outer dimensions including barrels with different exterior tapers. 
     Two elongated flanges  32  and  34  are located on each side of the split  24 . These flanges  32  and  34  each have three holes such as the holes  36  and  38  in them through which threaded screws  40  pass that are threaded into nuts such as the nut  42 . These screws  40  and nuts  42  can be tightened to clamp the flanges  32  and  34  together which results in the hole  18  being made smaller so that the sight mount  10  is clamped securely to the firearm muzzle end portion  12 . 
     The upper surface  44  of the sight mount body  16  is substantially flat and is rectangular shaped, when viewed from above such as in FIG. 3, with four corners  46 ,  48 ,  50  and  52  and with a projecting stud pattern portion  45  with four identical circular cross section cylindrical short projections or studs  54 ,  56 ,  58  and  60  extending upward at 90 degrees from the flat surface  44 . It is important that the height H of these projections  54 ,  56 ,  58  and  60  not be greater than one-half of the diameter D of these projections  54 ,  56 ,  58  and  60  that have equal diameters. This relationship is set forth below: 
     
       
         H=D/2 
       
     
     where: H is the maximum height of the projection  54 ,  56 ,  58  or  60   
     D is the diameter of the projection  54 ,  56 ,  58  or  60 . This relationship is necessary in order to ensure that the projections  54 ,  56 ,  58  or  60  are not subjected to forces upon firing that would result in excessive torque or other forces that would damage or distort these projections  54 ,  56 ,  58  or  60 . Such damage or distortion of the projection  54 ,  56 ,  58  or  60  would lead to the attached sight becoming loose and hence would prevent accurate shooting. 
     The upper surface  44  also has two identical circular threaded holes  62  and  64  in it and these holes  62  and  64  extend partially through the upper portion  66  of the sight mount body  16 . These holes  62  and  64  are used to accept screws (not shown) to attach a scope to the upper surface  44  of the upper portion  66  of the sight mount body. The projections  54 ,  56 ,  58  and  60  are located to mate with and be inserted into corresponding holes in the sight (not shown) or a sight adapter (not shown). The projections  54 ,  56 ,  58  and  60  are adapted to absorb most of the recoil upon firing rather than the screws that would be inserted into the holes  62  and  64 . 
     As illustrated in FIG. 4, although the aperture  18  in the sight mount body  16  has a generally circular cross section, it is deliberately not circular. Instead, a vertical slice has been taken out of a circle to form this cross section that is designated by the letter C. Consequently, the two opposite surfaces  68  and  70  are identical and form a portion of half of a circle with a radius R. However, the distance D′, that would be the diameter of the circle if the cross section C was a circle, is greater than the diameter that would equal twice the radius R. The relationship is set forth below: 
     
       
         D′=A+2×R 
       
     
     where: 0.05&lt;A&lt;0.10, 
     D′ is the distance across the aperture  18  from its top to its bottom, 
     R is the of the radius of the circle whose circumference matches the curved surface  68  or  70 . 
     It has been determined that this relationship results in the best gripping surfaces  68  and  70  when the sight mount body  16  is clamped to the outer surface of the firearm barrel muzzle portion  12 . 
     The second firearm sight mount embodiment is illustrated in FIGS. 5 through 7 and is designated by the number  80  and comprises an upper sight mount body  82  and a lower sight mount body  84  that are made from the same material as the sight mount body  16  that is strong but will bend or yield to some degree. The upper and lower sight mount bodies  82  and  84  are formed so that when they are secured together they form a centrally located generally circular cross section shaped aperture  86  that extends through the upper and lower sight mount bodies  82  and  84  from the forward surfaces  88  and  90  to the rearward surface  92  and  94  of the respective sight mount bodies  82  and  84 . The fact that the aperture  86  is formed by the two separate sight mount bodies  82  and  84  permits the right and left portions  96  and  98  of the upper sight mount body  82  to be spread apart slightly from the respective right and left portions  100  and  102  of the lower sight mount body  84  that are located around the hole  86  when the upper and lower sight mount bodies  82  and  84  are located at the desired location on the muzzle end barrel portion  12 . This permits the hole  86  to change its size and shape to accommodate muzzle end gun barrel portions  12  with different outer dimensions including barrels with different exterior tapers. 
     The two connecting side portions  96  and  98  are located on the upper sight mount body  82  adjacent the upper half circular curved surface  108  that forms part of the circular cross section aperture  86 . In a similar manner, the lower sight mount body  84  has the two elongated connecting side portions  100  and  102  located adjacent the lower half circular surface  116  that also forms part of the circular cross section aperture  86 . These connecting side portions  96  and  98  and  100  and  102  each have two respective identical holes  118   a ,  118   b , and  120   a ,  120   b , in them through which threaded screws  112  pass that are threaded into nuts such as the nuts  124 . These screws  112  and nuts  124  can be tightened to clamp the respective connecting side portions  96  and  98  and  100  and  102  together which results in the hole  86  being made smaller so that the sight mount  80  is clamped securely to the firearm muzzle end barrel portion  12 . 
     AS illustrated in FIG. 6, the upper surface  126  of the upper sight mount body  82  has a projecting stud pattern portion  117  that is is identical to the projecting stud pattern portion  45  located on the upper surface  44  of the sight mount body  16  of the previous firearm sight mount  10 . The upper surface  126  also has two identical circular threaded holes  128  and  130  that are similar to the threaded holes  62  and  64  of the previous embodiment  10  and these holes  128  and  130  extend partially through the upper sight mount body  82 . These holes  128  and  130  are adapted to accept screws (not shown) to attach a scope to the upper surface  126  of the sight mount body  82 . 
     As illustrated in FIG. 7, in a manner similar to that for the embodiment  10  and its aperture  18 , the aperture  86  formed by the upper and lower sight mount bodies  82  and  84  has a generally circular cross section, but it is intentionally not circular. Instead, a horizontal slice has been taken out of a circle to form this cross section that is designated by the letter F. Consequently, the two opposite surfaces  108  and  116  that are identical to the surfaces  68  and  70  of the sight mount embodiment  10  and each form a circle with a radius R that has the same relationship between D′ and A, namely D′=A+2×R of the first sight mount embodiment  10  as previously described and illustrated in FIG.  4 . 
     The third firearm sight mount embodiment is illustrated in FIGS. 8 and 9 and is designated by the number  132  and is substantially identical to the previously described second embodiment  80 , except for a minor modification to the upper sight mount body  82  of the previous embodiment  80 . In this connection, the upper sight mount body of the third embodiment  132  that is designated  134  is formed with a generally rectangular shaped circular cross section slot  136  in it that extends upward through the upper curved surface  108  from the forward surface  138  to the rearward surface  140  of the of the upper sight mount body  134 . This slot  136  is sized and shaped to receive the rib  144  that may be located on the top of the firearm forward barrel portion  12 . It will be noted that the upper sight mount body  134  has a greater height H 2  than the previous upper sight mount body  82  to accept the slot  136  and the web portion  146 . The connecting side portions  148  and  150  of the sight mount body  134  are similar to the connecting side portions  96  and  98  of the upper sight mount body  82  except that they have a greater height. 
     The firearm sight mount  10  and the other firearm sight mount embodiments  80  and  132  are made in the following manner. The unitary sight mount body  16  of the embodiment  10  and the sight mount bodies  82  and  84  and  134  of the other embodiments are cast from glass filled urethane plastic available from Dow Plastics, Dow Center of Midland, Mich. 48674. This casting is done using conventional plastic molding equipment known in the art and the resulting sight mount base  16  and sight mount bodies  82  and  84  and  134  need little if any outer surface machining or polishing. The holes  36  and  38  in the respective flanges  32  and  34  are formed during the injection molding process as are the holes  62  and  63  and  128  and  130  and  118   a  and  118   b  and  120   a  and  120   b . The screws  40  and  112  and nuts  42  and  124  are conventional off the shelf items. 
     The firearm sight mount  10  is used in the following manner. The screws  40  and nuts  42  are removed and the sight mount body  16  is spread apart at the split  24  as indicated by the arrows B in FIG.  4 . The sight mount body  16  is than mounted by slipping it onto the muzzle portion  12  of the firearm barrel with the flanges  32  and  34  passing on the sides of the sight  72  that is located on the upper side  74  of the firearm barrel muzzle portion  12 . After the flanges  32  and  34  have gone beyond the sight  72  the sight mount body  16  is inverted to its normal position and the screws  40  and associated nuts  42  are tightened to clamp the flanges  32  and  34  together and hence clamp the sight mount body  16  to the outer surface of the firearm barrel muzzle portion  12 . 
     The firearm sight mount  80  is used in the following manner. The screws  112  and nuts  124  are removed from the sight mount bodies  82  and  84 . The sight mount bodies  82  and  84  are then mounted on the muzzle portion  12  of the firearm barrel with the connecting side portions  96  and  100  and  98  and  102  located opposite each other on the sides of the firearm barrel muzzle portion  12  at the desired location on the firearm barrel muzzle portion  12 . The screws  112  are then inserted into the holes  118   a ,  118   b  and  120   a ,  120   b  and the associated nuts  124  are tightened to clamp the respective connecting side portions  96  and  100  and  98  and  102  together and hence clamp the sight mount bodies  82  and  84  of the firearm sight mount  80  to the outer surface of the firearm barrel muzzle portion  12 . 
     The fact that the sight mount body  16  is made from plastic allows it to deform slightly and hence allows the aperture  18  to be deformed to fit a particular barrel muzzle portion  12  configuration. As previously indicated, the particular dimensions D′ and R for the aperture  18  also provide excellent clamping of the surfaces  68  and  70  on the exterior surface of the firearm barrel muzzle portion  12 . In addition since the sight mount body and its clamping surfaces  68  and  70  are plastic this prevents marring of the outer surface of the firearm barrel muzzle portion  12  by the clamping surfaces  68  and  70 . The same advantages set forth above for the sight mount embodiment  10  also apply to the sight mount embodiments  80  and  132  and their plastic sight mount bodies  82  and  84  and  134  with their respective clamping surfaces  108  and  116 . 
     Although the invention has been described in considerable detail with reference to certain preferred embodiments, it will be understood that variations or modifications may be made within the spirit and scope of the invention as defined in the appended claims.