Abstract:
A construction for a firearm comprises an action, including a barrel, and a stock. The action is seated to the stock on a three-point bearing system comprising three bearings arranged in a triangular array. This provides for firm seating for the action and results in a more accurate firearm.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not applicable. 
     REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Conventional rifles employ a construction that includes an action coupled to a barrel and the combination is fitted to a stock. The action and barrel are usually metal parts whereas the stock is usually made of wood, plastic or other synthetic material. When firing the rifle, the user grips the stock, and when the firearm is fired, recoil is transmitted from the barreled action to the stock. Screws that are used to secure the action to stock extend perpendicularly to the direction of recoil forces. These joining members in combination with an imperfect bedding surface (i.e., imperfect mating of barreled action and stock) can cause the action to tilt, cock or be placed in a bind with respect to the stock and this affects the accuracy of the firearm. The fit of the stock and action also affects vibration. For example, most actions include a recoil lug, which is a downwardly extending flange that rests within a notch in the stock. The above-mentioned screws hold these pieces together. Connections between the action and the stock may result in cocking or misalignment because the joining surfaces do not always mate correctly when using conventional screws and a recoil lug. The stock/action interface may be inherently unstable if mating surfaces are uneven or if there are gaps, which can result in misalignment. Alignment is critical because the user always aims the firearm in the same manner, but if the action changes position relative to the stock during firing, prior zeroing of the rifle is rendered ineffective. 
     2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98 
     In the past, it has been proposed that metal pieces could be used in the stock to connect to the action and the barrel. Such a construction is shown in Dye (U.S. Pat. No. 3,206,885) and in Clerke (U.S. Pat. No. 3,830,003). The rifle constructions shown in these patents partially alleviate the problem but still fail to create a stable interface between the action and the stock. 
     BRIEF SUMMARY OF THE INVENTION 
     A construction for a firearm comprises an action, including a barrel, and a stock. The action is seated to the stock on a three-point bearing system comprising three bearings arranged in a triangular array. This provides for firm seating for the action and results in a more accurate firearm. 
     The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a partial side elevation view of a rifle including an action, a stock and a bedding block shown in ghost outline. 
         FIG. 2  is an exploded side elevation view of the rifle construction of  FIG. 1 . 
         FIG. 3  is a side elevation view of the rifle construction of  FIG. 1  showing selected internal parts in ghost outline. 
         FIG. 4  is a rear cutaway view taken along line  4 - 4 . 
         FIG. 5  is a front cutaway view taken along line  5 - 5 . 
         FIG. 6  is a side elevation partially-cutaway view of an embodiment in which the action includes a recoil lug. 
         FIG. 7  is a perspective view of a bedding block of the type used in  FIGS. 1-5 . 
         FIG. 8  is a perspective view of a bedding block of the type used in  FIG. 6 . 
         FIG. 9  is another embodiment of a bedding block for use in rifles having a slightly different construction. 
         FIG. 10  is a partial side cutaway view of a firearm showing an alternate embodiment in which bearings are formed in the stock material. 
         FIG. 11  is a partial side cutaway view of a firearm showing an alternate embodiment in which bearings are formed in the action. 
         FIG. 12  is a partial side cutaway view of a firearm showing an alternate embodiment in which the bearings are free floating. 
         FIG. 13  is a partial side cutaway view of another embodiment showing a firearm having a rounded action. 
         FIG. 14  is a cutaway view taken along line  14 - 14  of  FIG. 13 . 
         FIG. 15  is a cutaway view taken along line  15 - 15  of  FIG. 13 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     In one aspect of the invention, a three-point bearing interface is provided between the action and the stock or a bedding block. The three points are arranged to form a triangle, preferably an isosceles triangle, with two side-by-side bearings being located near the forward portion of the action and a single bearing located on an axial line midway between the two forward bearings and to the rear of the action. This is not an exclusive arrangement as design of the firearm may call for other locations for the bearings. The three bearing points, however, exclusively define the plane of interaction between action and stock and thus provide maximum strength and stability to the action/stock or bedding block interface and helps to prevent recoil forces from setting up inaccuracies due to uncontrolled, unrepeatable or inconsistent vibrations in the action and stock. The three bearings define a plane that extends generally parallel to the bottom surface of the action and the top surface of either the stock or a bedding block. There may be a gap between these surfaces, or the surfaces may touch but with very little compressive force. At least a slight gap is preferable. If desired, the gap may be partially or wholly filled with damping material, such as foam or felt, it being understood that the term “gap” as used herein is a spacing between the action and bedding block or stock surfaces whether or not damping material is interposed therein. 
     The bearing interface may be implemented in a number of ways. Bearing members may be cast or machined into lower surface portions of the action itself and recesses may be provided in the upper surface portions of the stock. If the stock is made of synthetic material, bearings may be formed in the stock material itself and recesses may be provided in the lower surface portions of the action or the bearing points may have no corresponding recesses. Finally, the bearings may “float”, that is, they may be separate elements that fit into recesses in the lower surface portions of the action and upper surface portions of the stock. If desired, the recesses and/or bearing members may be formed in metal inserts that are press fitted into slots in the stock. This is especially desirable when the stock material is much weaker than that used in the action. The recesses may be slightly oversized in at least one dimension relative to the bearing members so that perfect machining is not necessary for a good fit and to allow for some slight expansion and contraction. 
     The action is joined to the stock so as to apply compression at the three bearing points. Screws may be used which extend through holes in the stock and the action. The screws may secure a trigger guard plate to the bottom of the stock as well. When the screws are tightened providing compressive forces at the bearing points, it will be appreciated that a small gap may remain between bottom surface portions of the action and upper surface portions of the stock. In other words the action and stock are joined at the bearing points and may not be pressed together along their entire upper and lower surface portions respectively. This gap allows the bearings to be the exclusive interface between the action and stock so that the two pieces are held in position relative to one another at the three specified points. The gap also permits the use of damping material, such as a foam, which may be interposed in the gap to aid in damping vibration. Other materials, such as felt or rubber, could also be used. The use of such materials is optional, however, and may be omitted. 
     The bearings themselves may take several forms including the preferred spherical form, but cylinders, cones, pyramid shapes, and cubic or solid rectangles may work as well. 
     In another aspect of the invention, a bedding block may replace the interior of the stock so the action is never joined directly to the stock but to the bedding block. 
     Referring to  FIG. 1 , a rifle construction  10  includes an action  12  having a barrel  12   a  and a receiver  11 . The particular action  12  employed is a bolt action and, as such, includes a bolt  14  and a bolt handle  14   a . A stock  16  supports the action  12 . The rifle construction includes a trigger guard  39  and a floor plate  18 . A bedding block  20  is shown in dashed outline. The floor plate  18 , the action  12  and the bedding block  20  are all coupled together and surrounded by the stock  16  as will be explained below. 
     Reference is now made to  FIG. 7 , which illustrates the construction of the bedding block  20  shown in the embodiment of  FIG. 1 . The bedding block  20  is an insert made of a hard material, such as steel or Delrin®, that may be fastened inside the stock by glue. At its forward end, the bedding block  20  includes a pair of recesses  22   a  and  22   b . The recesses  22   a  and  22   b  reside within a steel insert  24 . The bedding block  20  may be made of a lighter material, such as aluminum, and the steel insert  24  provides the necessary tensile strength to support the parts and functions that will be described herein. The recesses  22   a  and  22   b  support a pair of side-by-side bearing members  26   a  and  26   b . These bearing members are preferably substantially spherical in shape, although other shapes for bearing members could also be employed such as cones, pyramids, cylinders or rectangular bearing members. In such cases, the mating recesses would be similarly shaped. A hole  28  extends through the bedding block between the recesses  22   a  and  22   b . The bedding block  20  includes an opening  30  through which a cartridge magazine (not shown) may extend. Alternatively, the magazine may be integral with the bedding block. A second opening  32  to the rear of the magazine opening  30  permits a trigger mechanism to extend through the block. Located behind the trigger opening  32  is a single recess  34 , which also includes a hole  36  that extends through the bedding block  20 . A single bearing member  38  rests in the recess  34 . Like bearing members  26   a  and  26   b , the bearing member  38  is preferably substantially spherical. However, unlike bearing members  26   a  and  26   b , the bearing member  38  includes a central hole  40 , which aligns with the hole  36  in the bedding block  20 . Collectively the three bearing members are arranged to define the three points of an isosceles triangle. 
     In  FIG. 2 , the bearing members  26   a  and  38  are free-floating bearings and fit within recesses  34 ,  22   a  in the bedding block  20  and in recesses  13 ,  15  in the action  12 . It will be appreciated that the bearings  38 ,  26   a ,  26   b  need not be free-floating but could be formed in the bedding block itself as substantially hemispherical protrusions or, alternatively, be formed in the action in the same manner. 
     Referring now to  FIG. 2 , the floor plate  18  is connected to the receiver  12  by threaded bolts or screws  42  and  44 . The screw  42  extends through a hole  36  in the bedding block  20  (shown best in  FIG. 5 ) and threadingly engages the action  12 . It should be noted that the hole  36  (see  FIG. 5 ) is oversized slightly with respect to the shaft of the screw  42 . To the rear of the trigger guard  39 , a screw  44  extends through a hole  28  in the bedding block  20  and threadingly engages the action  14 . The screw  44  extends through the bearing member  38 , which includes an accommodating hole  40 . Like the hole  36  at the forward end of the bedding block, the hole  28  (see  FIG. 4 ) is oversized relative to the shaft of a screw  44 . In both instances, this permits some reciprocal movement as will be explained below. 
     Referring to  FIG. 3 , it should be noted that the recess  34  in the bedding block is slightly elongated along the axis of the rifle with respect to the shape of the bearing  38 . Recess  22   a  is also slightly elongated perpendicular to the axis of the rifle. This allows nearly perfect alignment during assembly without perfect machining. Thus with the oversized holes and slightly elongated bearing recesses, the action may be joined to the bedding block such that the bearings will seat properly. 
     Screw-type fasteners are preferred for joining the bedding block to the action. The screws may be stock steel screws or may be made so as to allow them to flex. For example, a screw having a wound wire shank can flex slightly. In either case, the holes should be made slightly oversized with respect to the diameters of the screws so that there may be some slight movement within the holes without causing the bolt or screw to bind up or cock under the recoil forces generated when firing, or misalignment when the firearm is assembled. 
     Referring now to  FIG. 8 , a bedding block  70  is shown that is in all respects similar to the bedding block of  FIG. 7  with the exception that this embodiment may be used with a receiver which has a recoil lug  71  (see  FIG. 6 ). The front of the bedding block  70  has a cutaway portion  72 , which houses a steel insert  74 . As was the case with the embodiment of  FIG. 7 , the insert  74  includes recesses  76   a  and  76   b  into which spherical or ball bearings  78   a  and  78   b  are seated. The bedding block  70  has an opening  80 , which may function as a magazine, and a rear opening  82  for accommodating the trigger mechanism. A rear recess  84  houses the third ball bearing  86  of the three-point bearing system. Recesses  76   a  and  84  are slightly elongated. 
     Yet a different construction for the bedding block is shown in  FIG. 9 . In this construction, the rear bearing recess  92  and associated bearing  94  are situated between the magazine  96  and the trigger mechanism opening  98 . To accommodate a different stock construction, the front underside portion of the bedding block is cut away, leaving a forward flange  100 , which accommodates the steel insert  102 . As in  FIGS. 7 and 8 , the insert  102  houses side-by-side recesses  104   a  and  104   b , which receive spherical ball bearings  106   a  and  106   b  respectively. Recesses  104   a  and  92  are slightly elongated. 
       FIGS. 8 and 9  show that the construction of the rifle illustrated herein can be altered to accommodate different styles of firearms having differing internal dimensions and configurations. The construction described above eliminates inaccuracies inherent in the traditional way of coupling the action to the stock. The typical screw-type coupling between the action and the stock is avoided with the bedding block insert and bearings as described above. In this construction, there is no large flat mating surface between stock and receiver to cause problems in coupling the receiver to the stock. 
     The preferred embodiment provides the feature of a three-point bearing system, using three steel ball bearings as the contact points. The rear screw  44  goes directly through the center of the rear steel ball  38  and the forward two balls  26   a ,  26   b  are located directly to either side of the forward screw  42 . 
     The bedding block goes completely through to the bottom of the stock so that the screws tighten the floor plate  18  directly and solidly against the aluminum block  20 , drawing the barreled action  12  directly onto the ball bearings, and not into wood or synthetic stock material. Thus, there is no stock compression when the screws are tightened. The entire bedding system is metal on metal at three discrete points, virtually making one unit with the non-stress three-point system. 
     The stock is thus relegated to the role of a mere handle glued onto the bedding block and surrounding the important parts (important for accuracy) of the bedding block. With the metal system, there is no expansion or contraction, warping or twisting from temperature and humidity changes. The differential expansion/contraction in the aluminum/steel setup between the bedding block and steel inserts is so small over these short distances as to be insignificant over the ambient temperature range. 
     The screws  42  and  44  should permit perfect action seating and also allow for any tiny shift of fore-and-aft/lateral distance change. Also, the magazine box is incorporated directly into the bedding block. Therefore, there is no need for a separate magazine in the stock. 
     The system eliminates the necessity for detailed and sometimes complex stock cutouts and it eliminates the requirement for a recoil lug. The major features can be cast into an aluminum block with minimal machining. The steel inserts such as inserts  24 ,  74  and  102  may be pressed into the aluminum block with recesses formed to accept the steel ball bearings. 
     The system also eliminates the traditional weak points in the stock along either side of a typical magazine box. These relatively long and thin areas in the stock separate fore and aft bedding points on traditional stocks, which is a major problem regarding accuracy. The aluminum bedding block  20  and glue add strength in this important region of the stock  16 . The aluminum bedding block  20  also adds strength and protection around the complex and sometimes-delicate trigger mechanism  13 . All of this is hidden within the stock. The aesthetics of a fine wood stock can be realized along with the practical advantages of a synthetic stock. There are, in fact, more advantages in the aluminum bedding block than in a simple synthetic stock. The bedding block can also be used in a synthetic stock, if desired. 
     The bedding block may be cast and machined to dimensions that will fit the interior of the stock. The exterior dimensions of the bedding block are not critical and will be different, depending on the individual rifle into which it is fitted. The important points to consider when fitting it to a specific rifle are the location of the action screws specific to the rifle being used, and the fitting of the block to the floor plate to match the existing lines of a rifle stock. Again, these will vary, depending on the rifle being used. In addition, any cast-in, machined in, or separate recoil lug can be eliminated with this system. 
     Advantages can be gained, however, from the use of bearing members arranged in a three-point array even if a metallic bedding block is not used. For example, a substantial improvement over the existing interface between receiver and a stock made of wood or synthetic material can be realized if the stock is made of a strong enough material or contains a metallic insert having bearing members that interface with correspondingly shaped recesses. Referring to  FIG. 10 , an action  90  is coupled to a stock  92  with screws  94   a  and  94   b . In this case, the stock material includes a pair of formed bearing members situated forward of the trigger guard  96  and the magazine  98 . Only one forward bearing member  100  is shown in  FIG. 10 , but the second bearing is located on the opposite side of the stock. The screw  94   b  extends through a rear bearing member  102 . The bearing members  100 ,  102  and the second bearing member (which is not shown in  FIG. 10  but which is part of side-by-side pair similar to what is shown in  FIGS. 7-9 ) form an isosceles triangle. The action  90  includes recesses  104 ,  106  (only one of the recesses  104  is shown in  FIG. 10 ). When the bearings are mated with the recesses and the screws are tightened, the action is coupled to the stock leaving a small gap  108 . Thus, the action  90  and the stock  92  bear directly against each other only at the three-point bearing interface so that this interface takes the entire load of compression generated by the tightening of the screws. As with the embodiments employing the bedding block, the holes for the connecting screws are slightly oversized in diameter so recoil forces are not passed through a screw by setting up skewed force vectors between the action and the stock. 
     A similar structure is shown in  FIG. 11 , except in  FIG. 11  the bearing members  110  (opposite bearing member not shown) and  112  are formed in the action and recesses  111  and  113  are formed in the stock. When the action  101  is fastened down to the stock  103  by the screws  105 ,  107  a small gap  109  separates the remainder of the action  101  from the stock  103 . 
     A similar design is shown if  FIG. 12 , but in  FIG. 12 , instead of forming the bearings in the action or the stock material, the bearings are free floating. Thus, bearing  118  is one of a pair of forward bearings; the other bearing is not shown in  FIG. 12 . Bearing  118  sits in recesses  120 ,  122  formed in the stock and action respectively. Single bearing  124  situated to the rear of the magazine and the trigger sits in recesses  126  and  128  in the action and stock respectively. As was the case with the embodiments of  FIG. 10  and  FIG. 11 , a slight gap  130  exists between the action  121  and the stock  123  because the bearings  118  and its twin and bearing  124  take the compressive load imparted by the screws  131  and  133 . 
     Reference is now made to  FIGS. 13 ,  14  and  15 , which illustrate an embodiment in which the action has a rounded lower profile. The action  134  fits into the stock  136  on a three-point bearing interface, which includes forward bearings  138  and  140 , and a rear downwardly extending rectangular pad  142 , which fits within a correspondingly shaped recess  144  in the stock. If desired, a washer  145  may be used with the screw  148 . To conform to the curved surface of the stock, the washer  145  may be made of a resilient material such as a fibrous material or foam. Front and rear screws  146  and  148  join the stock to the action while leaving small gaps  150 ,  152  so that the three bearings  138 ,  140  and  142  bear the compressive forces. 
     With all of these designs, some recesses that accept the bearing members are slightly elongated perpendicular to the axis of the barrel while the rear recess may be elongated parallel to the barrel&#39;s axis. This is preferred but not required for the proper functioning of the three-point bearing system described herein. Further, depending upon the material of the stock, metallic inserts may or may not be required. For example, in the embodiment of  FIG. 11  where the bearings are formed into the action, metallic inserts housing the recesses could be used if the stock is made of wood or similar weaker material. The same is true of  FIG. 12  in which free-floating bearings are used. 
     Although the formed bearings in  FIGS. 12 through 17  have been shown mostly as substantially spherical (in the case of the floating bearings) or hemispherical (in the case of bearings formed in the stock and/or action themselves), other shapes including solid rectangles, cylinders, cones, or pyramid shapes could be used if desired. 
     The terms and expressions that have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.