Patent Publication Number: US-11397067-B2

Title: Position indexing feature for firearm with adjustable butt

Description:
RELATED APPLICATION 
     Under provisions of 35 U.S.C. § 119(e), Applicant claims the benefit of U.S. Provisional Application No. 63/022,020 filed May 8, 2020, the disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     A semi-automatic rifle may comprise a self-loading firearm whose action automatically cycles (i.e., ejects and rechambers) a new cartridge after each shot, but needs the operator to manually reset a hammer. The hammer needs to reset by relaxing the trigger before the next shot may be fired. Accordingly, only a single round may be discharged each time the trigger is depressed. In contrast, a fully-automatic (i.e., full-auto) rifle both cycles cartridges automatically and cycles (i.e., resets and releases) the hammer automatically as opposed to semi-auto firearms, which do only the former when the trigger is pulled. Consequently, for the duration of the trigger-pull, the full-auto rifle will fire multiple cartridges continuously until the full-auto rifle&#39;s magazine is depleted. 
     A firearm stock, often simply a stock, also known as a shoulder stock, a buttstock, is a part of a long firearm such as a rifle, to which the barreled action and firing mechanism are attached thereto and is held against the user&#39;s shoulder when shooting the firearm. The stock provides a means for the shooter to firmly support the firearm and easily aim with stability. The stock also transmits recoil into the shooter&#39;s body. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate various embodiments of the present disclosure. In the drawings: 
         FIG. 1A  shows an isometric view of a butt pad base; 
         FIG. 1B  shows a front view of a butt pad base; 
         FIG. 1C  shows a side view of a butt pad base; 
         FIG. 1D  shows a bottom view of a butt pad base; 
         FIG. 2A  shows an isometric view of a butt pad slide; 
         FIG. 2B  shows a front view of a butt pad slide; 
         FIG. 2C  shows a side view of a butt pad slide; 
         FIG. 2D  shows a bottom view of a butt pad slide; 
         FIG. 3A  shows a side view of a butt assembly in a zero position; 
         FIG. 3B  shows a cross section of a side view of a butt assembly in a zero position; 
         FIG. 4A  shows a side view of a butt assembly in a non-zero position; 
         FIG. 4B  shows a cross section of a side view of a butt assembly in a non-zero position; 
         FIG. 5  shows a bottom view of a butt assembly; 
         FIG. 6A  shows an isometric view of a butt assembly in a zero position; 
         FIG. 6B  shows an isometric view of a butt assembly in a non-zero position; and 
         FIG. 7  shows a side view of a butt assembly disposed on a rifle. 
     
    
    
     DETAILED DESCRIPTION 
     Overview 
     An apparatus that includes a position indexing feature for a firearm with an adjustable butt may be provided. The apparatus may comprise a butt pad base and a butt pad slide. The butt pad base may comprise a first slidable retention element and a marking face. The butt pad slide may comprise a second slidable retention element that slidably engages and retains the first slidable retention element, and a window through which at least a portion of the marking face is viewable. 
     Both the foregoing overview and the following example embodiments are examples and explanatory only, and should not be considered to restrict the disclosure&#39;s scope, as described and claimed. Further, features and/or variations may be provided in addition to those set forth herein. For example, embodiments of the disclosure may be directed to various feature combinations and sub-combinations described in the example embodiments. 
     EXAMPLE EMBODIMENTS 
     The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar elements. While embodiments of the disclosure may be described, modifications, adaptations, and other implementations are possible. For example, substitutions, additions, or modifications may be made to the elements illustrated in the drawings, and the methods described herein may be modified by substituting, reordering, or adding stages to the disclosed methods. Accordingly, the following detailed description does not limit the disclosure. Instead, the proper scope of the disclosure is defined by the appended claims. 
     Embodiments of the disclosure may allow a user (e.g., a shooter) to quickly and easily indicate and set a position of a butt (or butt assembly) on a firearm stock having a provision for vertical adjustment (i.e., indexing) of the butt position, while ensuring that the accuracy and reliability of the butt position indexing feature is preserved, and allowing an aesthetically-pleasing design to be maintained. Vertical adjustment of the butt may allow the shooter to tailor the basic “fit” of the stock to the shooter&#39;s body and may form a more natural interface between the shooter and the firearm, which may help the shooter to more easily make accurate shots with the firearm. 
     With a firearm, an optical sight (e.g., a scope) may be mounted in a position that may be high over a bore of the firearm. Vertical adjustment of the butt position may be desirable when aiming through the optical sight because the vertical adjustment may allow the shooter to bring an eye to meet the level of the optical sight while maintaining a natural relationship between the position of the butt against the shooter&#39;s shoulder, and the relative positions of the shoulder and eye. This may help to permit a natural shooter/stock interface, aiding in firearm accuracy. The ability to index (e.g., adjust vertically) the position of the butt may allow the shooter to make adjustments that may be more precise, recordable, more repeatable, and to make the adjustments more quickly than may be possible without embodiments of the disclosure. 
     Embodiments of the disclosure may include a butt pad base that may comprise a plate having, for example, a male dovetail feature centered upon it and extending the full length of the butt pad base, where the width of the male dovetail feature may be less than that of the butt pad base overall. This difference in width may create a “flat” feature (e.g., a marking face) that may be perpendicular to a centerline of a profile of the dovetail feature. The flat feature may comprise an area onto which is engraved or otherwise formed a set of markings comprising, for example, a series of numbers and horizontal line segments extending the length of the butt pad base. 
     Embodiments of the disclosure may further include a butt pad slide that may comprise a block of overall height and width equal to that of the butt pad base and may comprise, for example, a female dovetail feature corresponding to the male dovetail feature of the butt pad base. The butt pad slide may comprise a primary “notch cut” feature (e.g., a window) that may be located on a side of the butt pad slide. The window may include a secondary notch cut feature (e.g., a pointer). 
     When the butt pad base and the butt pad slide are joined via engagement between their respective dovetail features, the primary notch cut feature (i.e., the window) of the butt pad slide may reveal an area of the surface of the butt pad base (e.g., the marking face) onto which sets of numbers and line segments are marked, allowing a portion of the makings to be displayed. As either of the two parts (i.e., the butt pad base and the butt pad slide) move, constrained by their mating dovetail features, the secondary notch feature (e.g., the pointer) in the butt pad slide may be brought into alignment with the line segment markings on the butt pad base. This may provide a visible indication of the position of the two parts relative to each other. In the context of integrating the two parts in a rifle stock, embodiments of the disclosure may provide the user with a numbered or otherwise positively identifiable reading of a vertical position of the rifle&#39;s butt. 
     Embodiments of the disclosure may include a butt pad base that may have height position markings for indicating a vertical position of a firearm butt where, when the butt pad base is assembled as part of a rifle stock or firearm, the height position markings may be oriented other than parallel to a side of the rifle stock or firearm. Embodiments of the disclosure may further include a butt pad slide that may connect to the butt pad base and may have a geometry sufficient to cover/obscure the height position markings on the butt pad base when assembled, except that it includes one or more features which are able to be used to selectively reveal the height position markings, or to indicate/index the position of the butt pad slide relative to the height position markings. Embodiments of the disclosure may further include a dovetail (or similar) connection feature permitting linear movement of one the butt pad base and the butt pad slide relative to the other. Consequently, embodiments of the disclosure may allow for accurate, repeatable positioning of the vertically adjustable butt assembly in such a way that the markings are obscured from immediate view except as needed for positioning (aesthetically cleaner), and are protected from being rendered illegible over time due to abrasion/wearing off from normal handling/use, or by being covered by dirt/mud/debris, etc. 
       FIG. 1A ,  FIG. 1B ,  FIG. 1C , and  FIG. 1D  show a butt pad base  100 .  FIG. 1A  shows an isometric view of butt pad base  100 ,  FIG. 1B  shows a front view of butt pad base  100 ,  FIG. 1C  shows a side view of butt pad base  100 , and  FIG. 1D  shows a bottom view of butt pad base  100 . As shown in  FIG. 1A ,  FIG. 1B ,  FIG. 1C , and  FIG. 1D , butt pad base  100  may comprise a first marking face  105 , a second marking face  110 , a first slidable retention element  115 , a first stock frame post attachment orifice  120 , a second stock frame post attachment orifice  125 , and a length of pull adjustment element attachment orifice  130 . First marking face  105  may comprise a plurality of indexing elements  135  and a plurality of intermediate indexing elements  140 . Second marking face  110  may comprise a plurality of indexing elements similar to plurality of indexing elements  135  and a plurality of intermediate indexing elements  140  similar to plurality of intermediate indexing elements  140 . 
     As described in greater detail below, a first stock frame post  315  may attach to butt pad base  100  at first stock frame post attachment orifice  120 . A second stock frame post  320  may attach to butt pad base  100  at second stock frame post attachment orifice  125 . A length of pull adjustment element  325  may attach to butt pad base  100  at length of pull adjustment element attachment orifice  130 . 
     Butt pad base  100  that may comprise a plate having first slidable retention element  115  comprising, for example, a male dovetail centered on first slidable retention element  115  and extending the full length of butt pad base  100 . First slidable retention element  115  may comprise any type of slidable retention element including, but not limited to, a male dovetail or a female dovetail. 
     The width of first slidable retention element  115  may be less than that of butt pad base  100 . Consequently, this difference in width may create flat features (e.g., first marking face  105  and second marking face  110 ) that may be perpendicular to a centerline of a profile of first slidable retention element  115 . First marking face  105  may comprise an area onto which is engraved or otherwise formed plurality of indexing elements  135  and plurality of intermediate indexing elements  140 . 
     Plurality of indexing elements  135  and plurality of intermediate indexing elements  140  may comprise a set of markings comprising a series of numbers and horizontal line segments extending, for example, the length of butt pad base  100 . Plurality of indexing elements  135  and plurality of intermediate indexing elements  140  may be evenly spaced apart and plurality of intermediate indexing elements  140  may be respectively and evenly disposed between plurality of indexing elements  135 . For example, as shown in the example of  FIG. 1A  and  FIG. 1B , one of the plurality of indexing elements  135  may comprise “0” and subsequent ones of plurality of indexing elements  135  above and below “0” may be evenly graduated every 0.2 inches apart. Embodiments of the disclosure may use other units and may not be limited to inches. 
       FIG. 2A ,  FIG. 2B ,  FIG. 2C , and  FIG. 2D  show a butt pad slide  200 .  FIG. 2A  shows an isometric view of butt pad slide  200 ,  FIG. 2B  shows a front view of butt pad slide  200 ,  FIG. 2C  shows a side view of butt pad slide  200 , and  FIG. 2D  shows a bottom view of butt pad slide  200 . As shown in  FIG. 2A ,  FIG. 2B ,  FIG. 2C , and  FIG. 2D , butt pad slide  200  may comprise a second slidable retention element  205 , a window  210 , a first retention element orifice  215 , a second retention element orifice  220 , a first butt pad attachment orifice  225 , and a second butt pad attachment orifice  230 . Window  210  may comprise a pointer  235 . Window  210  may be disposed on one or both sides of butt pad slide  200 . 
     As described in greater detail below, a butt pad  305  may attach to butt pad slide  200  via first butt pad attachment orifice  225  and second butt pad attachment orifice  230 . Also as described in greater detail below, a first locking element  335  or a second locking element  340  may be disposed in first retention element orifice  215  and/or second retention element orifice  220 . 
     Second slidable retention element  205  may, fit around, slidably engage, and retain first slidable retention element  115 . Second slidable retention element  205  may comprise, for example, a female dovetail centered on second slidable retention element  205  and extending the full length of butt pad slide  200 . Second slidable retention element  205  may comprise any type of slidable retention element including, but not limited to, a male dovetail or a female dovetail. Butt pad slide  200  may comprise a block of overall height and width equal to that of butt pad base  100  and may comprise a female dovetail feature corresponding to the male dovetail feature of butt pad base  100 . Butt pad slide  200  may also comprise a primary “notch cut” feature (e.g., window  210 ) that may be located on one of both sides of butt pad slide  200 . Window  210  may include a secondary notch cut feature (e.g., pointer  235 ). At least a portion of first marking face  105  or second marking face  110  may be viewable through window  210  exposing ones of plurality of indexing elements  135  and ones of plurality of intermediate indexing elements  140  in window  210 . 
       FIG. 3A ,  FIG. 3B ,  FIG. 4A ,  FIG. 4B , and  FIG. 5  show a butt assembly  300 .  FIG. 3A  shows a side view of butt assembly  300  in a zero position.  FIG. 3B  shows a cross section of a side view of butt assembly  300  in a zero position (cross section “A” from  FIG. 3A ).  FIG. 4A  shows a side view of butt assembly  300  in a non-zero position.  FIG. 4B  shows a cross section of a side view of butt assembly  300  in a non-zero position (cross section “B” from  FIG. 4A ).  FIG. 5  shows a bottom view of butt assembly  300 . As shown in  FIG. 3A ,  FIG. 3B ,  FIG. 4A ,  FIG. 4B , and  FIG. 5 , butt assembly  300  may comprise butt pad base  100 , butt pad slide  200 , and butt pad  305 .  FIG. 3A ,  FIG. 3B ,  FIG. 4A , and  FIG. 4B  further illustrate a stock frame  310 , a first stock frame post  315 , a second stock frame post  320 , a length of pull adjustment element  325 , a length of pull adjustment wheel  330 .  FIG. 4B , and  FIG. 5  further illustrate first locking element  335 , and second locking element  340 . 
     Butt assembly  300  may be attached to stock frame  310  via first stock frame post  315  and second stock frame post  320 . First locking element  335  may comprise, but is not limited to, a screw and length of pull adjustment wheel  330  may comprise, but is not limited to, a corresponding nut associated with first locking element  335 . As length of pull adjustment wheel  330  is adjusted (e.g., rotated clockwise or counter clockwise), the horizontal distance between butt assembly  300  and stock frame  310  may be correspondingly adjusted. 
     When butt pad base  100  and butt pad slide  200  are joined via engagement between their respective slidable retention elements (i.e., respective dovetail features), window  210  of butt pad slide  200  may reveal an area of first marking face  105  or second marking face  110  onto which plurality of indexing elements  135  and plurality of intermediate indexing elements  140  may be marked, allowing a portion of plurality of indexing elements  135  and plurality of intermediate indexing elements  140  to be displayed and viewed by a user. As either of the two parts (i.e., butt pad base  100  and butt pad slide  200 ) move, constrained by their mating respective slidable retention elements (i.e., respective dovetail features), pointer  235  in window  210  of butt pad slide  200  may be brought into alignment with the line segment markings (e.g., ones of plurality of indexing elements  135  and plurality of intermediate indexing elements  140 ) on butt pad base  100 . This may provide a visible indication of the position of the two parts (i.e., butt pad base  100  and butt pad slide  200 ) relative to each other. In the context of integrating butt assembly  300  in rifle stock frame  310 , embodiments of the disclosure may provide the user with a numbered or otherwise positively or negatively identifiable reading of a vertical position of the rifle&#39;s butt pad  305 . 
       FIG. 6A  shows an isometric view of butt assembly  300  in a zero position and  FIG. 6B  shows an isometric view of butt assembly  300  in a non-zero position.  FIG. 7  shows a side view of butt assembly  300  disposed on a rifle  700  that includes a bore  705 . Embodiments of the disclosure may include butt pad base  100  that may have height position markings (e.g., plurality of indexing elements  135  and plurality of intermediate indexing elements  140 ) for indicating a vertical position of butt pad  305 . When butt assembly  300  is assembled as part of stock frame  310  of rifle  700 , the height position markings (e.g., plurality of indexing elements  135  and plurality of intermediate indexing elements  140 ) may be oriented other than parallel to a side of stock frame  310  or rifle  700 . 
     The user of rifle  700  may loosen first locking element  335  and/or second locking element  340  to allow first slidable retention element  115  and second slidable retention element  205  to slide with respect to one another. This may allow the user to line pointer  235  with ones of plurality of indexing elements  135  and plurality of intermediate indexing elements  140 . Pointer  235  lining up to the ones of plurality of indexing elements  135  and plurality of intermediate indexing elements  140  may indicate a distance a top of butt pad  305  attached to butt pad slide  200  is above a center of bore  705  of rifle  700  or below the center of bore  705  of rifle  700 . 
     As shown in  FIG. 6A , for example, pointer  235  may be lined up with the “0” indexing element. This may indicate that the top of butt pad  305  may be with a center of bore  705  of rifle  700 . Similarly, as shown in  FIG. 6B , pointer  235  may be lined up with the “0.6” indexing element. This may indicate that the top of butt pad  305  may be 0.6 inches above the center of bore  705  of rifle  700 . Lining up pointer  235  with the intermediate indexing element between indexing element “0.6” and indexing element “0.8” above the “0” indexing element may indicate the top of butt pad  305  may be 0.7 inches above the center of bore  705  of rifle  700 . Once the user of rifle  700  lines pointer  235  with a desired indexing element or intermediate indexing element, the user may tighten first locking element  335  and/or second locking element  340  to inhibit first slidable retention element  115  and the second slidable retention element  205  from sliding with respect to one another. 
     Consistent with embodiments of the disclosure, a plane containing a line passing through a center of bore  705  of rifle  700  may be substantially perpendicular to a plane containing first marking face  105  and/or second marking face  110 . Consequently, embodiments of the disclosure may allow for accurate, repeatable positioning of vertically adjustable butt assembly  300  in such a way that the markings (e.g., plurality of indexing elements  135  and plurality of intermediate indexing elements  140 ) are obscured from immediate view except as needed for positioning (aesthetically cleaner), and are protected from being rendered illegible over time due to abrasion/wearing off from normal handling/use, or by being covered by dirt/mud/debris, etc. 
     Rifle  700  may comprise, for example, a bolt action firearm or a self-loading firearm that may comprise, for example, a semi-automatic rifle or a fully-automatic rifle. Embodiments of the disclosure are not limited to an particular types of firearms and may be used on any other types of firearms including, but not limited to, shotguns, carbines, and pistols for example. 
     Embodiments of the present disclosure, for example, are described above with reference to block diagrams and/or operational illustrations of methods and systems, according to embodiments of the disclosure. The functions/acts noted in the blocks may occur out of the order as shown in any flowchart. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality/acts involved. 
     While the specification includes examples, the disclosure&#39;s scope is indicated by the following claims. Furthermore, while the specification has been described in language specific to structural features and/or methodological acts, the claims are not limited to the features or acts described above. Rather, the specific features and acts described above are disclosed as example for embodiments of the disclosure.