Abstract:
This disclosure describes systems, methods, and apparatus for a selectable barrel support that can be inserted into a forend of a firearm stock to support a first barrel type and flipped, rotated, or otherwise moved to support a second barrel type (or third or fourth barrel types). Bull and tapered barrels are examples of two barrel types that the selectable barrel support can be used to support. The selectable barrel support enables a firearm owner or gunsmith to exchange barrel types on a firearm without having to switch out the firearm stock.

Description:
FIELD OF THE INVENTION 
     The present invention relates to firearms. In particular, but not by way of limitation, the present invention relates to systems and methods for firearm stocks. 
     BACKGROUND OF THE INVENTION 
     Rifles often can be fitted with two primary types of barrels: tapered or bull barrels (also known as target barrels or heavy barrels). The bull or target barrel typically has a non-tapered or cylindrical shape, whereas a tapered barrel (typically affixed to most firearms) is tapered toward the muzzle such that the diameter at the muzzle is less than a diameter at the receiver. The non-tapered nature of bull barrels means that they are steadier due to greater weight, less prone to vibration due to their geometry, and can absorb more thermal energy due to their greater mass of metal (and hence are less prone to warping under repeated firing), and are therefore preferred in some applications. Most firearm stocks are shaped to support either of these barrel types, but not both. This means that users who wish to switch barrel types must buy and install an entirely new stock when installing a new barrel. U.S. Pat. No. 8,056,278 provides one solution to this problem in the form of a stock that supports a bull barrel and an insert that can be fitted into the stock to support a tapered barrel. Thus, the &#39;278 patent enables a change in barrel types without the purchase and installation of an entirely new barrel. However, this design suffers from the need to store and keep track of the insert when the stock is used with a bull barrel and hence without the insert. 
     One application where the switching of barrels occurs is the RUGER 10/22, a widespread .22 caliber rifle platform. The RUGER 10/22 includes a safety pin that is perpendicular to the barrel and arranged on the top front portion of the trigger guard just below the stock. When the trigger guard is inserted into the stock the safety pin must clear an opening in the bottom of the stock shaped to pass the trigger guard. However, the safety pin will impinge one or another side of this opening unless the safety pin is ‘centered’ in the trigger guard such that neither end of the safety pin extends beyond the sides of the trigger guard. 
     SUMMARY OF THE DISCLOSURE 
     Exemplary embodiments of the present invention that are shown in the drawings are summarized below. These and other embodiments are more fully described in the Detailed Description section. It is to be understood, however, that there is no intention to limit the invention to the forms described in this Summary of the Invention or in the Detailed Description. One skilled in the art can recognize that there are numerous modifications, equivalents and alternative constructions that fall within the spirit and scope of the invention as expressed in the claims. 
     Some embodiments of the disclosure may be characterized as a selectable barrel support of a firearm stock. The selectable barrel support can include an elongate frame and first and second concave barrel recesses. The elongate frame can have a longitudinal axis configured to be parallel to a longitudinal axis of the firearm stock, the elongate frame can have a greater longitudinal dimension than a lateral dimension. The first concave barrel recess can have radii at fore and aft portions of the first concave barrel recess shaped to support a first barrel type. The second concave barrel recess can have a radii at fore and aft portions of the second concave barrel recess shaped to support a second barrel. The first and second concave barrel recesses can be arranged on two separate sides of the elongate frame. One of the first and second concave barrel recesses can be configured to face upward toward a bottom of a barrel of the firearm when the selectable barrel support is engaged in the forend of the firearm stock. 
     Other embodiments of the disclosure may also be characterized as a firearm stock. The firearm stock can include a forend, a buttstock, and a selectable barrel support. The forend can include a recess formed from first and second inner sides of the forend and an inside bottom of the forend. The buttstock can be coupled to the forend. The selectable barrel support can include an elongate frame, first and second sides, and first and second concave barrel recesses. The elongate frame can have a longitudinal dimension configured to be parallel to a longitudinal axis of the forend. The first and second sides can be shaped to interface with the first and second dinner sides of the forend. The first concave barrel recess can have a radius at a fore portion of the concave barrel recess that is equal to or greater than a radius at an aft portion of the concave barrel recess. The second concave barrel recess can have a greater radius at an aft portion of the second concave barrel recess than at a fore portion of the second concave barrel recess. The first and second concave barrel recesses can be on opposite sides of the elongate frame. One of the first and second concave barrel recesses can be configured to face upward toward a bottom of a barrel of the firearm when the selectable barrel support is engaged in the forend of the firearm stock 
     Other embodiments of the disclosure can be characterized as a method of attaching a reversible barrel support to a firearm stock. The method can include removing a reversible barrel support from a recess in a forend of a firearm stock, wherein the reversible barrel support has a first concave barrel recess facing upward. The method can further include rotating the reversible barrel support over such that a second concave barrel recess of the reversible barrel support faces upward. The method can yet further include inserting the reversible barrel support back into the recess in the forend. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various objects and advantages and a more complete understanding of the present invention are apparent and more readily appreciated by referring to the following detailed description and to the appended claims when taken in conjunction with the accompanying drawings: 
         FIG. 1  shows a firearm stock including a selectable barrel support implemented in a complete firearm; 
         FIG. 2  shows another view of the stock of  FIG. 1 ; 
         FIG. 3  shows yet another view of the stock of  FIG. 1 ; 
         FIG. 4  shows an exploded view of the stock of  FIG. 1 ; 
         FIG. 5  shows the selectable barrel support of  FIGS. 1-4 ; 
         FIG. 6  shows another view of the selectable barrel support of  FIGS. 1-4 ; 
         FIG. 7A  shows an additional view of the selectable barrel support of  FIGS. 1-4 ; 
         FIG. 7B  shows an additional view of the selectable barrel support of  FIGS. 1-4 ; 
         FIG. 8  shows a cross section of the trigger guard region of the firearm of  FIG. 1 ; 
         FIG. 9  shows another cross section of the trigger guard region of the firearm of  FIG. 1  but without showing the action; 
         FIG. 10  shows yet another top view of the trigger guard region of the firearm of  FIG. 1  but without showing the action; 
         FIG. 11  shows a cross sectional view of the trigger guard region of the firearm of  FIG. 1  but without showing the receiver; 
         FIG. 12  shows another cross sectional view of the trigger guard region of the firearm of  FIG. 1  but without showing the receiver; 
         FIG. 13  shows yet another cross sectional view of the trigger guard region of the firearm of  FIG. 1  but without showing the receiver; 
         FIG. 14  shows a method of attaching a reversible barrel support to a firearm stock; 
         FIG. 15  shows another embodiment of a selectable barrel support; and 
         FIG. 16  shows yet another embodiment of a selectable barrel support. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure discusses a firearm stock including at least a selectable barrel support insert shaped to support at least two different barrel types or shapes, for instance either a tapered or bull barrel. In a particular embodiment, this discussion enables a bull barrel or barrel tapered toward a front of the barrel to be used in a firearm stock without requiring a change of the firearm stock. 
       FIGS. 1-4  illustrate different views of an embodiment of a firearm stock and selectable barrel support according to one embodiment of this disclosure. The selectable barrel support can be reversible, and therefore a selectable barrel support includes at least a reversible barrel support.  FIG. 1  shows the firearm stock  100  including the selectable barrel support  120  (see  FIGS. 2-4 ) implemented in a complete firearm  101 . The stock  100  can include a forend  102  and a buttstock  104  coupled to each other, or further including a grip section  106  coupled between the forend  102  and the buttstock  104 . In some embodiments, these two or three components can be modular and detachable. Modular means that a firearm user or a firearm manufacturer can combine any two modular parts to form a functional assembly. For instance, different forends  102  can be combined with different buttstocks  104  or different grip sections  106 . In this way, the stock  100  can be manufactured in polymer at far less cost than if the whole stock  100  were manufactured as a single component. 
     The firearm  101  having the stock  100  can further include a receiver  108 , a trigger assembly  110 , and a barrel  112  coupled to the receiver  108 . The barrel can rest on the selectable barrel support  120 . 
     The forend  102  can extend from behind the receiver  108  to a front end of the forend  114 . The illustrated stock  100  is shown with a receiver  108  and a trigger assembly  110  inserted in the stock  100 . The forend  102  can include a recess  116  formed from first and second inner sides  121 ,  123  and an inside bottom  125 . The forend  102  can include a selectable barrel support  120  (see  FIGS. 2-4 ) shaped to fit into the recess  116  in the forend  102 , and can include an elongate frame having a longitudinal axis  138  (see  FIGS. 7A and 7B ) parallel to a longitudinal axis of the stock  100 . A longitudinal dimension  140  of the selectable barrel support  120  extending from proximal a front end of the forend  114  to proximal a front end of the receiver  108  of the firearm  101  along the longitudinal axis  138  can be greater than a lateral dimension  142  of the elongate frame. The selectable barrel support  120  can include a first side  122  and a second side  124  (see  FIGS. 5-6 ), each side  122 ,  124  shaped to fit a respective inner side  121 ,  123  of the stock  100 . The shape of the first and second sides  122 ,  124  and the respective inner sides  121 ,  123  can be such that the selectable barrel support  120  releasably forms a snap, friction, or interference fit with the recess  116  in the forend  102 . 
     The selectable barrel support  120  includes a first concave barrel recess  126  and a second concave barrel recess  128 , each arranged on separate sides (e.g., opposing or adjacent sides) of the selectable barrel support  120 , and each configured to support a different type of barrel when the selectable barrel support  120  is engaged in the forend  102  of the firearm stock  100 . However, the selectable barrel support  120  can also be configured to support more than two different barrel types. In the illustrated embodiment, the first concave barrel recess  126  is shaped to support a tapered barrel, while the second concave barrel recess  128  is shaped to support a bull barrel or competition barrel. To do this, the first concave barrel recess  126  has radii at fore and aft portions shaped to support a first barrel type (e.g., a tapered barrel  112 ), and the second concave barrel support  128  has radii at fore and aft portions shaped to support a second barrel type. In particular, the firearm  101  of  FIG. 1  has a tapered barrel  112 , and the first concave barrel recess  126  of the selectable barrel support  120  faces upward toward the barrel  112  and supports the barrel  112 . In this embodiment, the first concave barrel recess  126  has a greater radius at an aft portion  132  than at a fore portion  134 . The second concave barrel recess  128  is illustrated with an equal radius at fore and aft portions  134 ,  132  of the first concave barrel recess  126 . However, the second concave barrel recess  128  can have a radius at the fore portion  134  that is equal to or greater than a radius at the aft portion  132  (e.g., where a bull barrel or competition barrel has a reverse taper—tapering from the muzzle toward the chamber). Said another way, the radii at the fore and aft portions of the first concave barrel recess  126  can be equal and the radii at the fore and aft portions of the second concave barrel recess  128  can be unequal. 
     In some embodiments, the first and second concave barrel recesses  126 ,  128  can be configured to support barrel types other than bull or tapered barrels. For instance, one type of supported barrel can include a stepped or staggered barrel having two or more cylindrical sections, where no two adjoining sections have the same radius. Other barrel types may taper toward a middle of the barrel and then flare toward the opposing end, thus very roughly being referred to as an hourglass shape (e.g., an M16 barrel). Other barrel types may include a combination of steps as well as tapering. Some barrel types can use a stepped or staggered shape to approximate a tapered barrel (i.e., an average radius of the barrel along its length tapers). Whatever the barrel types, the first and second concave barrel recesses  126 ,  128  can be configured and shaped to support any one or more barrel types (e.g., bull, tapered, staggered, hourglass, etc.), such that rotating the selectable barrel support  120  allows two or more different barrel types to be installed on the firearm  101  without a change in the stock  100 . 
     The selectable barrel support  120  has been shown and described as having two concave barrel recesses  126 ,  128 . Yet, in other embodiments, three or more concave barrel recesses can be implemented. For instance, a selectable barrel support (or a rotatable barrel support) having three sides, and one concave barrel recess in each of those three sides, can be implemented (see, for example,  FIG. 15 ). In such an embodiment, the forend  102  can include a recess  116  shaped like a “V”, having angled ribs to support two of the three sides of the selectable barrel support, or any other structure shaped to support and/or engage with the three-sided selectable barrel support. In another embodiment, the concave barrel recess can include four sides, each having a concave barrel recess configured to support a different barrel type (see, for example,  FIG. 16 ). 
       FIG. 15  shows yet another embodiment of a selectable barrel support. The selectable barrel support  1500  includes three sides  1502 ,  1504 ,  1506  each arranged on separate (or adjacent) sides of the selectable barrel support  1500 , and each configured to support a different type of barrel when the selectable barrel support  1500  is engaged in the forend of a firearm stock. At least the first concave barrel recess  1508  is illustrated as shaped to support a tapered barrel, and the figure is shown from an aft perspective such that a muzzle of a barrel supported by the tapered barrel support  1500  would be directed into the page. 
       FIG. 16  shows yet another embodiment of a selectable barrel support. The selectable barrel support  1600  includes four sides  1602 ,  1604 ,  1606 ,  1608  each arranged on separate sides of the selectable barrel support  1600 , and each configured to support a different type of barrel when the selectable barrel support  1600  is engaged in the forend of a firearm stock. At least the first concave barrel recess  1610  is illustrated as shaped to support a tapered barrel, and the figure is shown from a fore perspective such that a muzzle of a barrel supported by the tapered barrel support  1600  would be directed out the page. One of the four concave barrel recesses  1610 ,  1612 ,  1614 ,  1616 , and it&#39;s corresponding side  1602 ,  1604 ,  1606 ,  1608  would typically be arranged facing upward toward a barrel of a firearm, while an opposing side  1602 ,  1604 ,  1606 ,  1608  would face downward into the forend of the firearm. As illustrated, the fourth side  1608  and the fourth concave barrel recess  1616  face upwards towards where a barrel might reside, while the opposing side, the second side  1604 , as well as its corresponding second concave barrel recess  1612 , face downward. The second and fourth concave barrel recesses  1612 ,  1616  are shaped to support a bull barrel, while the first concave barrel recess  1610  is shaped to support a tapered barrel. 
     Returning to  FIG. 1 , the selectable barrel support  120  is inserted in the stock  100  such that the first concave barrel recess  126  is oriented upward to support a barrel  112  (e.g., a tapered barrel) while the second concave barrel recess  128  is oriented downward toward a bottom of the recess  116  of the forend  102 . In this arrangement, the barrel  112  can rest in the first concave barrel recess  126  and contact the selectable barrel support  120 . Similarly, when the second concave barrel recess is oriented upward toward the barrel  112 , the barrel  112  can rest in the second concave barrel recess  128  and contact the selectable barrel support  120 . However, the selectable barrel support  120  can also be used with free-float barrels or assemblies and in these cases, while a free-float barrel may fit partially into the first and/or second barrel recesses  126 ,  128 , the barrel does not contact the selectable barrel support  120 . In the illustrated embodiments, the first and second concave barrel recess  126 ,  128  have a longitudinal dimension  144  that is less than the longitudinal dimension  140  of the selectable barrel support  120 . 
     To enable the selectable barrel support  120  to be releasably held in the forend  102  to the firearm stock  100 , the selectable barrel support  120  can be shaped so as to have a snap fit, friction fit, or interference fit with the recess  116  (e.g., a snap, friction, or interference fit with one or more of the first inner side  121 , the second inner side  123 , and the inside bottom  125 ). Alternatively, and as illustrated, the selectable barrel support  120  can include one or more optional fastener apertures enabling optional fasteners  136  to be used to secure the selectable barrel support  120  to the stock  100  or to the forend  102  (these are not required as the barrel  112  can also perform the role of holding the selectable barrel support  120  to the stock  100 ). The illustrated embodiment includes three optional fasteners  136  with corresponding apertures in the forend  102 , but this number is not limiting, and greater than or less than three can be implemented. In some cases, no fasteners are implemented. For instance, the selectable barrel support  120  may be releasably held in place via a snap, friction, or interference fit with the first and second inner sides  121 ,  123 . The releasable hold on the selectable barrel support  120  can be aided by contact with a bottom of the barrel  112 . In other instances, limited or no friction between the barrel support  120  and the forend  102  exists, and instead, contact from a bottom of the barrel  112  holds the barrel support  120  in place. Further, in some instances, a combination of fasteners, and a snap, friction, or interference fit can be implemented. While the illustrated optional fasteners  136  are round-head screws, other types of fasteners can also be used without departing from the scope and spirit of the disclosure. 
     In some embodiments, the firearm stock  100  can also include structure to assist a firearms user to insert the trigger assembly  110  into the stock  100  (see  FIGS. 8-13 ). A typical safety pin  170  of the trigger assembly  110  has two stable manufacturer-intended positions: fire or safe. In both of these positions, the safety pin  170  extends laterally from the trigger assembly  110  perpendicularly to the longitudinal axis of the stock  100 . For instance, in  FIGS. 8, 11, and 13  the safety pin  170  extends to a left of the trigger assembly  110 , which can either be a safe or fire position, depending on specifications of the firearm  101 . In order to insert the trigger assembly  110  into the stock  100  or remove the trigger assembly  110  from the stock  100 , the trigger assembly  110  must pass at least partially through an aperture  143  (e.g., having a substantially rectangular shape). In the safe or fire positions, the safety pin  170  typically extends beyond a perimeter of the aperture  143  (see  FIG. 11 ), and thus the trigger assembly  110  cannot pass at least partially through the aperture  143  while the safety pin  170  is in either the safe or fire positions (e.g., either extending to the left or right of the trigger assembly  110 ). Therefore, a user typically ‘centers’ the safety pin  170  between the safe and fire positions, which is an unstable arrangement not intended by manufacturers and one not easily achieved or maintained while the trigger assembly  110  is being passed through the aperture  143 . 
     To overcome this challenge, the herein disclosed stock  100  can include angled faces  146  that are adjacent to the first and second inner sides  121 ,  123  and the inside bottom  125  of the stock  100 . These angled faces  146  are shaped to urge the safety pin  170  to the ‘centered’ position (i.e., centered across the trigger assembly  110 , see for instance,  FIG. 12 ) when the trigger assembly  110  is inserted into the stock  100  and passed at least partially through the rectangular aperture  143 . Once the safety pin  170  has passed through the aperture  143 , the safety pin  170  can return to the safe or fire position under the force of its own internal structure (i.e., since the ‘centered’ position of  FIG. 12  is unstable), as shown in  FIG. 13 . 
     The stock  100  is illustrated as being configured for a RUGER 10/22 platform, other firearms platforms, including other .22 caliber firearms and firearms of different calibers, can also use the herein disclosed features. 
       FIG. 14  illustrates a method of attaching a selectable (or reversible) barrel support to a firearm stock. The method  1400  includes removing a reversible barrel support from a recess in a forend of a firearm stock, wherein the reversible barrel support has a first concave barrel recess facing upward (Block  1402 ). For the purposes of this disclosure, upward can reference a vector starting at a bottom of a forend and traversing toward a barrel of the firearm. In an embodiment, this reversible barrel support can be shaped to fit two different barrel types, for instance a bull or competition barrel, and a tapered barrel tapering from the chamber toward the muzzle. The first concave barrel recess can be shaped to support a first barrel type, and a second concave barrel recess can be shaped to support a second barrel type. Where either or both barrel types are floating, the term “support” may not include physical contact between the reversible barrel support and the one or more floating barrels. The reversible barrel support may be releasably held in place via a snap, friction, or interference fit with first and second inner sides of the forend. This releasable hold on the reversible barrel support can be aided by contact with a bottom of the barrel. In other instances, limited or no friction between the barrel support and the forend exists, and instead, contact from a bottom of the barrel holds the barrel support in place. The method  1400  further includes flipping the reversible barrel support over such that a second concave barrel recess of the reversible barrel support faces upward (Block  1404 ), and inserting the reversible barrel support back into the recess in the forend (Block  1406 ). The method  1400  can be reversed and can be repeated as many times as desired. Further, the method  1400  can be implemented when switching between any two different types of barrels. 
     The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. Those skilled in the art can readily recognize that numerous variations and substitutions may be made in the invention, its use and its configuration to achieve substantially the same results as achieved by the embodiments described herein. Accordingly, there is no intention to limit the invention to the disclosed exemplary forms. Many variations, modifications and alternative constructions fall within the scope and spirit of the disclosed invention as expressed in the claims.