FIREARM HANDGUARD ATTACHMENT AND ALIGNMENT SYSTEM

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63/693,739, filed 12 September 2024, the disclosure of which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

This invention relates to a mechanism and system for attachment and alignment of a firearm handguard or forearm.

BACKGROUND

A firearm handguard or forearm provides a gripping surface for the shooter’s hand, protecting the hand from potentially injurious heat of the barrel and providing a platform for mounting accessories, such as optics, sights, rangefinders, bipods, etc. In the popular AR-pattern platform, the barrel is attached to the upper receiver at the proximal or chamber end. It is important that this attachment be secure against both longitudinal and rotational displacement.

SUMMARY OF THE INVENTION

The present invention provides a mechanism or system for securing a handguard to a receiver, such as an AR-pattern upper receiver, to secure it against both longitudinal and rotational displacement. According to an aspect of one embodiment, the barrel nut includes circumferential splines on an exterior surface thereof that can be engaged by at least one gear that has complementary splines. The at least one gear may be an interiorly threaded insert and the complimentary splines may be arranged on an exterior surface thereof and extend longitudinally along an axis of the insert. Rotation of the interiorly threaded insert draws the handguard toward the receiver. According to another aspect of an embodiment, a pair of wedges with rearwardly extending alignment fingers that engage the upper receiver and can be drawn together in a clamping action to secure the handguard against rotational displacement.

According to an embodiment of the present disclosure, a system for a firearm is disclosed, wherein the firearm comprises an upper receiver, a barrel, and a handguard. Here, the system comprises a barrel nut having driven splines on an exterior surface of the barrel nut, wherein the barrel nut is arranged on the barrel and the upper receiver, and a gear having drive splines on an exterior surface thereof, wherein the gear is arranged on the handguard and the drive splines of the gear engage the driven splines of the barrel nut, and wherein rotation of the gear in one direction moves the handguard toward the upper receiver.

According to another embodiment consistent with the present disclosure, a system for a firearm is disclosed, wherein the firearm comprises an upper receiver, a barrel, and a handguard. Here, the system comprises a first wedge part that carries a first alignment finger, the first wedge part having an elongated opening. The system also includes a second wedge part that carries a second alignment finger, the second wedge part having a threaded opening, wherein the first and second wedge parts are arranged in a cavity at a proximal end of the handguard, and the handguard includes a hole that extends into the cavity. The first and second alignment fingers project rearwardly toward and along opposite sides of the upper receiver and, when the handguard is assembled on the upper receiver and the barrel, the alignment fingers are adjustable to clamp onto the opposite sides of the upper receiver to prevent relative rotation between the handguard and the upper receiver. Further, the system includes an adjustment screw that extends through the hole in the handguard and the elongated opening in the first wedge part and threads into the threaded opening of the second wedge part, and wherein interfacing surfaces of the first and second wedge parts are correspondingly angled so that the first and second wedge parts move laterally, thereby clamping the first and second alignment fingers onto the upper receiver, as the adjustment screw is tightened.

According to another embodiment consistent with the present disclosure, a system for securing and aligning a handguard relative to a firearm comprising an upper receiver and a barrel is disclosed. The system comprises an attachment mechanism configured to attach the handguard to the firearm and an alignment mechanism configured to maintain the handguard in a desired rotational position relative to the upper receiver. The attachment mechanism comprises a barrel nut having driven splines on an exterior surface thereof, wherein the barrel nut is arranged on the barrel and the upper receiver, and a gear having drive splines on an exterior surface thereof, wherein the gear is arranged on the handguard and the drive splines of the gear engage the driven splines of the barrel nut, and wherein rotation of the gear in one direction moves the handguard toward the upper receiver. The alignment mechanism comprises a first wedge part, a second wedge part, and an adjustment screw. The first wedge part carries a first alignment finger, and the first wedge part includes an elongated opening. The second wedge part carries a second alignment finger, the second wedge part includes a threaded opening, and the first and second wedge parts are arranged in a cavity at a proximal end of the handguard. The first and second alignment fingers project rearwardly toward and along opposite sides of the upper receiver and, when the handguard is assembled on the firearm, and the alignment fingers are adjustable to clamp onto the opposite sides of the upper receiver to prevent relative rotation between the handguard and the upper receiver. The adjustment screw extends through an opening in the handguard and the elongated opening in the first wedge part and threads into the threaded opening of the second wedge part, wherein the opening in the handguard extends into the cavity of the handguard. Interfacing surfaces of the first and second wedge parts are correspondingly angled so that the first and second wedge parts move laterally, thereby clamping the first and second alignment fingers onto the upper receiver, as the adjustment screw is tightened.

According to another embodiment consistent with the present disclosure, a handguard system for a firearm comprising an upper receiver and a barrel is disclosed. The system includes an elongated tubular handguard having a proximal end at which the handguard is attachable to the firearm, a barrel nut arranged on the barrel and the upper receiver, wherein driven splines are arranged on an exterior surface of the barrel nut, and a gear having drive splines on an exterior surface thereof, wherein the gear is arranged on the handguard and the drive splines of the gear engage the driven splines of the barrel nut, and wherein rotation of the gear moves the handguard toward the upper receiver.

According to yet another embodiment consistent with the present disclosure, a handguard system for a firearm comprising an upper receiver and a barrel is disclosed. The system includes an elongated tubular handguard having a proximal end at which the handguard is attachable to the firearm, wherein the proximal end of the handguard includes a cavity and the handguard further includes a hole that extends into the cavity. The system also includes a first wedge part that carries a first alignment finger, the first wedge part having an elongated opening, and a second wedge part that carries a second alignment finger, the second wedge part having a threaded opening, wherein the first and second wedge parts are arranged in the cavity of the handguard. The first and second alignment fingers project rearwardly toward and along opposite sides of the upper receiver and, when the handguard is assembled on the upper receiver and the barrel, the alignment fingers are adjustable to clamp onto the opposite sides of the upper receiver to prevent relative rotation between the handguard and the upper receiver. The system also includes an adjustment screw that extends through the hole in the handguard and the elongated opening in the first wedge part and threads into the threaded opening of the second wedge part. Interfacing surfaces of the first and second wedge parts are correspondingly angled so that the first and second wedge parts move laterally, thereby clamping the first and second alignment fingers onto the upper receiver, as the adjustment screw is tightened.

According to yet another embodiment consistent with the present disclosure, a handguard system for a firearm comprising an upper receiver and a barrel is disclosed. The system includes an elongated tubular handguard having a proximal end at which the handguard is attachable to the firearm, wherein the proximal end of the handguard includes a cavity and the handguard further includes a hole that extends into the cavity. The system also includes a barrel nut arranged on the barrel and the upper receiver, wherein driven splines are arranged on an exterior surface of the barrel nut, and a gear having drive splines on an exterior surface thereof, wherein the gear is arranged on the handguard and the drive splines of the gear engage the driven splines of the barrel nut, and wherein rotation of the gear moves the handguard toward the upper receiver. The system also includes a first wedge part that carries a first alignment finger, the first wedge part having an elongated opening, and a second wedge part that carries a second alignment finger, the second wedge part having a threaded opening, wherein the first and second wedge parts are arranged in the cavity of the handguard. The first and second alignment fingers project rearwardly toward and along opposite sides of the upper receiver and, when the handguard is assembled on the upper receiver and the barrel, the alignment fingers are adjustable to clamp onto the opposite sides of the upper receiver to prevent relative rotation between the handguard and the upper receiver. In addition, the system includes an adjustment screw that extends through the hole in the handguard and the elongated opening in the first wedge part and threads into the threaded opening of the second wedge part, wherein interfacing surfaces of the first and second wedge parts are correspondingly angled so that the first and second wedge parts move laterally, thereby clamping the first and second alignment fingers onto the upper receiver, as the adjustment screw is tightened.

Other aspects, features, benefits, and advantages of the present invention will become apparent to a person of skill in the art from the detailed description of various embodiments with reference to the accompanying drawing figures, all of which comprise part of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Like reference numerals are used to indicate like parts throughout the various drawing figures, wherein:

FIG. 1 is an isometric view of an AR-pattern upper receiver and a handguard according to an embodiment of the present invention;

FIG. 2 is another isometric enlarged view of the connection between the handguard and upper receiver;

FIG. 3 is an isometric, partially exploded view of the connection between the handguard and upper receiver;

FIG. 4 is an alternate isometric exploded view of a handguard attachment and alignment system with a barrel and barrel nut;

FIG. 5 is an isometric view of the connection between the upper receiver and an embodiment of the handguard attachment and alignment system with the handguard partially cut away;

FIG. 6 is an enlarged side sectional view of the connection between the upper receiver and an embodiment of the handguard attachment and alignment system taken substantially along line 6—6 of FIG. 2;

FIG. 7 is a cross-sectional view taken substantially along line 7—7 of FIG. 1;

FIG. 8 is an enlarged isometric view of the alignment mechanism according to one embodiment of the invention in a first, unclamped position;

FIG. 9 is an enlarged isometric view of the alignment mechanism according to one embodiment of the invention in a second, clamped position;

FIG. 10 is an enlarged cross-sectional view of the alignment system taken substantially along line 10—10 of FIG. 6 when in the first, unclamped position; and

FIG. 11 is an enlarged cross-sectional view of the alignment system of FIG. 10 when in the second, clamped position.

DETAILED DESCRIPTION

With reference to the drawing figures, this section describes particular embodiments and their detailed construction and operation. Throughout the specification, reference to "one embodiment," "an embodiment," or "some embodiments" means that a particular described feature, structure, or characteristic may be included in at least one embodiment. Thus, appearances of the phrases "in one embodiment," "in an embodiment," or "in some embodiments" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the described features, structures, and characteristics may be combined in any suitable manner in one or more embodiments. In view of the disclosure herein, those skilled in the art will recognize that the various embodiments can be practiced without one or more of the specific details or with other methods, components, materials, or the like. In some instances, well-known structures, materials, or operations are not shown or not described in detail to avoid obscuring aspects of the embodiments. “Forward” will indicate the direction of the muzzle and the direction in which projectiles are fired, while “rearward” will indicate the opposite direction. “Lateral” or “transverse” indicates a side-to-side direction generally perpendicular to the axis of the barrel or the axis of the handguard. Although firearms may be used in any orientation, “left” and “right” will generally indicate the sides according to the user’s orientation, “top” or “up” will be the upward direction when the firearm is gripped in the ordinary manner. “Handguard” and “forearm” are used interchangeably herein.

The present disclosure is directed toward a handguard or forearm system for a firearm. The handguard or forearm system (hereinafter, the handguard system) includes a handguard or forearm attachment (hereinafter, the handguard) that is connectable to an upper receiver and/or a barrel of the firearm and, as described herein, the handguard system is operable for attaching the handguard on the firearm and/or the handguard system is operable for aligning the handguard relative to the firearm. The handguard system may also include a barrel nut with exterior splines and at least one gear that meshes with the splines of the barrel nut, and the gear is carried by the handguard such that rotation of the gear pulls the handguard or forearm attachment toward the upper receiver when the barrel nut is arranged on the upper receiver and the barrel. The handguard system may also include a pair of wedges with rearwardly extending alignment fingers that engage the upper receiver and can be drawn together in a clamping action to secure the handguard against rotational displacement and thereby secure the handguard in a desired rotational orientation about an axis of the barrel relative to the upper receiver.

FIGS. 1-11 depict a firearm 9 that is utilizable with aspects of the present disclosure. The firearm 9 includes an AR-pattern upper receiver 10 and a barrel 16. The upper receiver 10 includes a forward or distal end 15 and a threaded projection 20 at the distal end 15. The barrel 16 includes a chamber (or proximal) end 17 and a barrel extension 24 at the chamber end 17, and an annular flange 22 is formed on the barrel extension 24. When the firearm 9 is assembled, the chamber end 17 is positioned proximate to the distal end 15 and the barrel extension 24 is in alignment with the threaded projection 20, and the barrel 16 extends distally (and away) from the upper receiver 10 along an axis A. In an AR-pattern firearm, such as the firearm 9, the barrel 16 is secured to the upper receiver 10 with a barrel nut that threads onto the threaded projection 20 of the upper receiver 10, over the annular flange 22 of the barrel extension 24 at the chamber end 17 of the barrel 16 in a well-known manner.

FIGS. 1-11 also depict a handguard system 1 for the firearm 9, according to one or more embodiments. In the illustrated embodiments, the handguard system 1 includes a handguard 12 and, as previously mentioned, the handguard system 1 is configured to secure the handguard 12 to the firearm 9 and/or to align the handguard 12 relative on the firearm 9. The handguard 12 includes a proximal end 14 that is in close proximity to or abuts the distal end 15 of the upper receiver 10 when assembled, and the handguard 12 extends distally (away from) the upper receiver 10 along the axis A. In the illustrated embodiments, the handguard 12 is an elongate tubular member that is hollow, such that the handguard 12 defines an inner bore 19. The system 1 is operable to secure the handguard 12 to the upper receiver 10, with the barrel 16 extending through and “free floating” within the bore 19 of the handguard 12. Thus, the system 1 allows the barrel 16 to remain “free floating,” meaning that the handguard 12 is connected to the barrel 16 or receiver 10 only at the chamber end 17 of the barrel 16 and does not otherwise need to have any additional contact with the barrel 16. Stated differently, the barrel 16 is connected to the firearm 9 only at the chamber end 17 thereof, and does not otherwise connect the handguard 12 as the barrel 16 extends distally through the handguard in a direction away from the receiver 10 (i.e., toward a muzzle or distal end of the barrel 16 or firearm 9).

The length of the handguard 12 is measured along the axis A and is typically determined by the length of the barrel 16 and, thus may be longer or shorter than as shown herein. Moreover, while the handguard is depicted as being generally tubular, with an octagonal shape, it may have other shapes or lengths without departing from the present disclosure. Further, the handguard 12 may have other or different features than as illustrated, without departing from the present disclosure.

As mentioned above, the system 1 may be configured to both secure the handguard 12 to the firearm 9 and to maintain the handguard 12 in a desired rotational position/orientation about the axis A relative to the upper receiver 10. For this reason, the system 1 may be referred to as the attachment and alignment system 1. For example, in the illustrated embodiments, the system 1 includes both (i) a firearm handguard or forearm attachment mechanism 100 (hereinafter, the attachment mechanism 100) that secures the handguard 12 to the firearm 9 and (ii) a handguard or forearm alignment mechanism 102 (hereinafter, the alignment mechanism 102) that secures/maintains the handguard 12 in a desired rotational position/orientation relative to the upper receiver 10. However, in other non-illustrated embodiments, the system 1 includes either (i) the attachment mechanism 100 or (ii) the alignment mechanism 102. Thus, the attachment mechanism 100 and the alignment mechanism 102 may be used separately or together; however, regardless of whether the system 1 includes either or both of the attachment mechanism 100 and/or the alignment mechanism 102, the system 1 may simply be referred to as “the system 1”. With regard to the figures, FIGS. 1-7 depict both the attachment system 100 and the alignment mechanism 102 utilized with the firearm 9, according to one or more embodiments, while FIGS. 8-11 depict just the alignment mechanism 102 utilized with the firearm 9, according to one or more embodiments.

As mentioned, FIGS. 1-7 depict the attachment mechanism 100 of the system 1, according to one or more embodiments. In the illustrated embodiments, the attachment mechanism 100 of the system 1 includes the handguard 12, a barrel nut 18, and a gear 26 that engages the barrel nut 18. Not only does the barrel nut 18 couple and secure the barrel 16 to the upper receiver 10, but the barrel nut 18 includes splines 18 arranged on an exterior surface 21 of the barrel nut 18. Also in the illustrated embodiment, the gear 26 includes splines 34 arranged on an exterior surface 23 of the gear 26 that mesh with and engage with the splines 28 of the barrel nut 18. In the illustrated embodiment, the splines 28 of the barrel nut 18 are circumferential splines that are each provided as a ring that is oriented in a plane that is substantially perpendicular to the axis A, and the splines 34 of the gear 26 are longitudinal splines 34 that each extend longitudinally in a direction/orientation that is substantially parallel to an axis B of rotation of the gear 26 associated therewith.

In the illustrated embodiment, the gear 26 is configured as an internally threaded insert that extends along the axis B and includes a drive head 27 and a threaded bore or socket 38. The drive head 27 may be configured to receive an Allen wrench or other tool, such that rotation may be imparted on the gear 26 via the drive head 27. As mentioned below, the gear 26 is arranged on the handguard 12 and, in the illustrated embodiments, a corresponding threaded fastener 30 is threadable into the threaded socket 38 to secure the gear 26 to the handguard 12. Also, because the gear 26 is driven, for example, via a tool that engages the drive head 27, the gear 26 is the drive gear and the splines 34 thereof are the drive splines of the system 1, and the barrel nut 18 is the driven gear and the splines 28 thereof are the driven splines of the system 1. In embodiments, the corresponding fastener 30 is a bolt or other type of threaded fastener.

In the illustrated embodiment, a fastener assembly 31 is provided for clamping and securing the handguard 12 to the firearm 9. Here, the fastener assembly 31 includes a nut 33 and a threaded fastener 35. The threaded fastener 35 may be a bolt of the same or different type as the fastener 30. In other non-illustrated embodiments, instead of using the fastener assembly 31, a second gear (similar to the gear 26) and second fastener (similar to the fastener 30) is utilized.

Referring first to FIGS. 1-5, therein is shown the handguard 12 according to various embodiments. In the illustrated embodiment, includes the handguard 12 is configured to be clampable to the barrel nut 18 via the fastening assembly 31. As detailed above, the gear 26 is also secured to the handguard via the fastener 30, and the gear 26 and the fastener 30 may also function to help clamp the handguard 12 onto the barrel nut 18, for example, when the fastener 30 is screwed and tightened onto the gear 26. Also in the illustrated embodiment, a longitudinal split 32 is defined in the proximal end 14 of the handguard 12 which allows the handguard 12 to be clamped to the barrel nut 18, to thereby prevent relative longitudinal movement of the handguard 12. As shown, the handguard 12 includes a pair of bottom tabs 41 and 43 that are separated by the longitudinal split 32, with the first bottom tab 41 extending from a first side 45 of the handguard 12 and the second bottom tab 43 extending from a second side 47 of the handguard 12.

In the illustrated embodiments, the barrel nut 18 and gear 26 are configured to interact with each other in order to draw the handguard 12 to the upper receiver 10. Then, the fastener assembly 31 may be utilized to clamp the handguard 12 onto the barrel nut 18 and in close proximity to the upper receiver 10, thereby securing the handguard 12 in place. Here, a first pair of aligned openings 36 is formed adjacent the rear end 14 of the handguard 12 body and the gear 26 and corresponding fastener 30 extend transversely through the first pair of aligned openings 36. In particular, the first pair of aligned openings 36 includes a first opening 36 in the tab 41 and an aligned second opening 36 formed in the tab 43, and the gear 26 and corresponding fastener 30 extend transversely through the openings 36 in the tabs 41 and 43. Also in the illustrated embodiment, a second pair of aligned openings 36 is formed in the handguard 12 (e.g., in the tabs 41 and 43) and the threaded fastener 35 of the fastening assembly 31 extends there-through. When the threaded fastener 35 and the nut 33 are tightened together, the tabs 41 and 43 are drawn and pulled together such that the handguard 12 may be clamped onto the barrel nut 18 and/or the upper receiver 10.

When the gear 26 is arranged in the handguard 12 and, in particular, when the gear 26 is arranged in the aligned opening 36 of the handguard 12, the splines 34 of the gear 26 at least partially extend into the bore 19 of the handguard 12. In this manner, when a user is assembling the handguard 12 on the firearm 9 and positions the handguard 12 over the barrel nut 18, such that the barrel nut 18 is at least partially within the bore 19 of the handguard 12, the splines 34 of the gear 26 are able to engage and mesh with the splines 28 of the barrel nut 18. Thus, the aligned opening 36 of the handguard 12 are formed so that the gear 26 and the splines 34 thereof are positioned in a suitable manner where they may engage/mesh with the splines 28 of the barrel nut 18. This is depicted in at least FIGS. 5-7.

Referring now also to FIG. 6, by engagement between the respective splines 28, 34 (which interact as gear teeth), rotation of the gear 26 draws the handguard 12 rearward toward the upper receiver 10. In the FIG. 6 view, counterclockwise rotation of the gear 26 (via the drive head 27 thereof) will draw the handguard 12 toward the left (toward the upper receiver 10). Thus, the splines 28 on the barrel nut 18 could be characterized as a cylindrical gear “rack” that functions in any rotational position of the barrel nut 18 about the axis A (i.e., the splines 28 function regardless of how or whether the barrel nut 18 is rotated about the axis A) and the splines 34 of the gear 26 could be characterized as “pinion” gears that engage with the barrel nut splines 28. While the splines 28 of the barrel nut 18 are circumferential rings oriented in a plane that is perpendicular to the axis A and the gear splines 34 are longitudinal and oriented substantially parallel to the axis B (and perpendicular to the axis A) in the illustrated embodiment, in other embodiments the splines of the barrel nut 18 could be helical (like relatively fine threads) and the splines on the gear 26 could be at a corresponding pitch.

Referring now also to FIG. 7, the corresponding fastener 30 axially threads into the threaded socket 38 of the gear 26 (i.e., the corresponding fastener 30 threads into a free end of the internally threaded insert on which the splines 34 are provided). A tool (not shown) configured to engage the drive head 27 of the gear 26 is used to rotate the gear 26 and held with the handguard 12 drawn toward the upper receiver 10 as the corresponding fastener 30 is threaded into the socket 38 and tightened. This draws the handguard 12 toward the upper receiver 10, secures the gear 26 in place against rotation, and clamps the handguard 12 to the barrel nut 18 by drawing together opposite sides (i.e., the opposite tabs 41 and 43) of the longitudinal split 32. Then the fastener assembly 31 may be utilized to further clamp and secure the handguard 12 on the firearm 9, but holding the nut 33 (e.g., with another tool) while rotating the threaded fastener 35 (e.g., via the tool). In the illustrated embodiment, the clamping fastener 30 is coaxial with the internally threaded insert (of the gear 26), but could be situated on separate axes and thread into a threaded socket (not shown) on an opposite side of the longitudinal split 32. Likewise, the internally threaded insert (of the gear 26) does not have to span the entire lateral dimension (or width as measured between the tabs 41 and 43) of the longitudinal split 32 and, for example, could be positioned laterally at one or both sides, or at the top of the handguard 12.

According to another aspect of present disclosure, the system 1 (also or instead) includes the alignment mechanism 102 to assure the handguard 12 maintains the desired rotational position relative to the upper receiver 10. As shown at least in FIGS. 2-4, the upper receiver 10 includes opposing side surfaces 64 and 66 and an accessory rail 48, with the opposing side surfaces 64 and 66 located beneath the accessory rail 48. Referring now to FIGS. 3-5 and 8-11, the alignment mechanism 102 provides alignment fingers 40 that project rearwardly toward the upper receiver and along each side 64 and 66 of the upper receiver 10, just below the top accessory rail 48. The standard profile of a 1913 MIL-SPEC accessory rail (sometimes referred to as a Picatinny rail) includes surfaces below the dovetail extensions, so a typical upper receiver 10 can be utilized with the alignment mechanism 102 without special design or modification. The alignment fingers 40 may be laterally adjusted toward each other to produce a clamping action against the opposite surfaces 64 and 66 of the upper receiver 10 to prevent relative rotation between the handguard 12 and the upper receiver 10.

The alignment mechanism includes first and second wedge parts 42, 44, each of which carry one of the alignment fingers 40 (described above). In particular, the first wedge part 42 carries a first alignment finger 40a of the pair of alignment fingers 40, and the second wedge part 44 carries a second alignment finger 40b of the pair of alignment fingers 40.

The handguard 12 includes a handguard accessory rail 50 on an upper side of the handguard 12, wherein the handguard accessory rail 50 aligns with the accessory rail 48 of the upper receiver 10 when the handguard 12 is assembled thereon. As best shown in at least FIGS. 3-4, a cavity 46 is formed in the proximal end 14 of the handguard 12 for receiving the wedge parts 42 and 44. Here, the cavity 46 is formed just beneath the accessory rail 50 and located such that the aligned FIGS. 40 extending from the wedge parts 42 and 44 will extend along the side surfaces 64 and 66 of the upper receiver 10 when assembled. Thus, the wedge parts 42, 44 fit into the cavity 46 formed under the handguard accessory rail 50 at the proximal end 14 of the handguard 12, as shown at least in FIGS. 2-3, FIGS. 5-6, and FIGS. 8-11.

The top of the accessory rail 50 includes a laterally elongated guide hole 52 that extends into (and is in communication with) the cavity 46 and is configured to receive an adjustment screw 54. The first wedge part 42 (sometimes referred to as the upper wedge part 42) includes an enlarged opening 56, and the second wedge part 44 (sometimes referred to as the lower wedge part 44) includes a threaded opening 58 that is configured to threadably receive the adjustment screw 54. Due to the enlarged nature of the enlarged opening 56 relative to the threaded opening 58 (i.e., the lateral dimension or width of the enlarged opening 56 is larger than that of the threaded opening 58), the threaded opening 58 may correspond and align with the enlarged opening 56 in the upper wedge part 42 as the first and second wedge parts 42 and 44 move laterally with respect to each other.

The laterally elongated guide hole 52 is elongated in the lateral or width dimension, for example, in a dimension that extends between the sides 45 and 47 of the handguard 12. In particular, the laterally elongated width dimension of the guide hole 52 is larger than a diameter of the adjustment screw 54, such that the laterally elongated guide hole 52 provides “play” or space for the adjustment screw 54 to shift side to side as the alignment mechanism 102 is actuated as discussed below. Also, the laterally elongated guide hole 52 and the adjustment screw 54 may be correspondingly countersunk. For example, the adjustment screw 54 may have be a countersunk adjustment screw having a countersunk screw head and the guide hole 52 may be include a counter sunk recess configured or formed for receiving the screw head in a manner that allows the screw head to be flush with a surface of the handguard 12 into which the guide hole 52 is formed.

In the illustrated embodiments, the laterally elongated guide hole 52 and the enlarged opening 56 in the first wedge part 42 are both unthreaded, while the threaded opening 58 in the second wedge part 44 includes threads that correspond with the threads of the adjustment screw 54. Thus, as shown, the adjustment screw 54 passes through (or extends through) the laterally elongated guide hole 52 and the enlarged opening 56 in the first (upper) wedge part 42, and the adjustment screw 54 then threads into the threaded opening 58 in the second (lower) wedge part 44. The wedge parts 42 and 44 include interfacing surfaces 60, 62 that are correspondingly angled or inclined and, when assembled, the interfacing surfaces 60, 62 of the wedge parts 42, 44 are in contact with each other, such that the wedge parts 42 and 44 will slide laterally on and relative to each other as they are forced together. Stated differently, the interfacing surfaces 60, 62 of the wedge parts 42, 44 are correspondingly angled so that, as the adjustment screw 54 is tightened, the wedge parts 42, 44 shift laterally toward a center, wherein the center may be defined by a vertical plane that extends through the axis A (i.e., a vertical center plane). This, in turn, draws together the alignment fingers 40 into clamping contact with the opposite side surfaces 64, 66 of the upper receiver 10 (compare FIGS. 8 and 9 and compare FIGS. 10 and 11). The laterally elongated guide hole 52 for the adjustment screw 54 in the handguard 12 body and the enlarged opening 56 in the first (upper) wedge part 42 allow any needed lateral shifting movement as the wedge parts 42, 44 are drawn together. The adjustment screw 54 can be locked with any common mechanical means or thread adhesive, if desired.

In one example utilization of the alignment mechanism 102, the user will position the handguard 12 in close proximity to the upper receiver 10, with the fingers 40 extending over and in close proximity to (but not necessarily in contact with) the surfaces 64 and 66 of the upper receiver 10. The wedge parts 42 and 44, and their corresponding alignment fingers 40, are in a first or unclamped position at this time. The user will then use a tool to rotate the adjustment screw 54, which is threadably engaged with the lower wedge part 44. As the adjustment screw 54 is tightened, the lower wedge part 44 translates upward along the adjustment screw 54 and, as the lower wedge part 44 translates upward, the interfacing surface 62 thereof contacts the interfacing surface 60 of the upper wedge part 42. As the lower wedge part 44 continues to translate upward due to rotation of the screw 54, the interfacing surface 62 continues to press against the interfacing surface 60 of the upper wedge part 42, which causes the interfacing surface 60 of the upper wedge part 62 to slide on the interfacing surface 62 of the lower wedge part 60, thereby resulting in the upper wedge part 60 moving laterally inward toward the center. As the upper wedge part 42 to slides on the lower wedge part 44 toward the center, the alignment finger 40a of the upper wedge part 42 comes into contact with the side surface 66 of the upper receiver 10, thereby halting further movement of the upper wedge part 42. Rotation of the adjustment screw 54 also causes the lower wedge part 44 to move laterally inward, toward the center, until the alignment finger 40b carried thereon comes into contact with the side surface 64 of the upper receiver 10. As the lower wedge part 44 moves inward in this manner, the adjustment screw 54 correspondingly moves in the same direction, as the adjustment screw 54 is effectively carried by the lower wedge part 44 when the screw 54 is engaged in the threaded opening 58. This lateral movement of the screw 54 with the lower wedge part 44, towards the side 47 of the handguard 12, is permitted due to the clearance (or “play”) provided by the laterally elongated/enlarged hole 52 and 56 in the handguard 12 and the laterally elongated/enlarged opening 56 in the upper wedge part 42. Once both of the wedge parts 42 and 44 have been fully repositioned inward by rotation of the screw 54, such that alignment fingers 40 are securely engaged with the upper receiver 10, the wedge parts 42 and 44 and their corresponding alignment fingers 40 are in a second or clamped position. Thus, during installation of the handguard 12 on the upper receiver via the alignment mechanism 102, the clamping force generated by the tightening screw 54 acts against two angled planes of the interfacing surfaces 60 and 62 between the two wedge parts 42 and 44, causing the wedge parts 42 and 44 (and the alignment fingers 40a and 40b carried thereon) to self-adjust to the exact size and position of the upper receiver 10, allowing for a rapid and proper alignment of the handguard12 with the upper receiver 10.

While one or more embodiments of the present invention have been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. Therefore, the foregoing is intended only to be illustrative of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not intended to limit the invention to the exact construction and operation shown and described. Accordingly, all suitable modifications and equivalents may be included and considered to fall within the scope of the invention, defined by the following claim or claims.