HYBRID POLYMER LOWER RECEIVERS FOR FIREARMS AND METAL THREADED INSERTS, KITS AND METHODS THEREFOR

Abstract

Threaded metal inserts for polymer lower receivers and hybrid polymer lower receivers comprising one or more of such inserts, as well as kits and methods therefor are disclosed. A threaded metal insert has a substantially circular aperture configured with screw threads to releasably yet connectively interface with a separate traditionally threaded firearm component such as a buffer tube or a pistol grip screw. Inserts can be any overall shape so long as it can be integrally embedded within a traditionally threaded portion of a polymer lower receiver in a way that does not interfere with normal operation of an assembled firearm and leaves exposed the internal threading of the insert. Inserts can also comprise textural features on the exterior surface configured to permanently interface with and embed the an insert into molded polymer. A hybrid polymer and metal lower receiver is a stripped polymer lower receiver for an AR type firearm, such as the AR-15 or AR-10, having one or more such threaded metal inserts at least partially embedded in a portion thereof.

Claims

1. A threaded insert for a polymer receiver for a firearm, comprising: (a) an insert body sized and shaped to be at least partially embedded within said receiver; (b) an aperture extending linearly through at least a portion of said insert body; (c) screw threads for releasable connection with a traditionally threaded component of a receiver assembly for a firearm; and (d) an exterior circumference with one or more textural features configured to interface with and retain a polymer.

2. The threaded insert of claim 1, wherein said insert maintains the structural integrity of said receiver and does not interfere with normal use and operation of said firearm.

3. The threaded insert of claim 1, wherein said traditionally threaded component of a firearm receiver assembly is a buffer tube or a pistol grip retaining screw.

4. The threaded insert of claim 1, wherein said aperture is approximately 0.248 or 1.00 inches in diameter.

5. The threaded insert of claim 1, wherein said screw threads are mil-spec or comm-spec threads.

6. The threaded insert of claim 1, wherein said insert is made from a metallic material that enables said screw threads to withstand sustained contact with a metal buffer tube during repeated discharge of said firearm.

7. The threaded insert of claim 1, wherein said insert is substantially cylindrical or ring-shaped.

8. The threaded insert of claim 1, wherein said textural features comprise relief channels, relief cuts, notches, divots, depressions, knurling, cross-hatching, shallow holes, and pits.

9. The threaded insert of claim 1, wherein the exterior circumference of said insert comprises a combination of knurling and relief channels, relief cuts, or notches.

10. The threaded insert of claim 9, wherein said relief channels, relief cuts, or notches are disposed on said exterior surface at an angle substantially perpendicular to a longitudinal axis extending through said aperture.

11. The threaded insert of claim 1, wherein said insert is integrally molded or at least partially embedded within a portion of a polymer lower receiver for a firearm.

12. The threaded insert of claim 11, wherein said portion of a polymer lower receiver is a buffer tube collar or a pistol grip attachment point.

13. The threaded insert of claim 1, further comprising: (e) a polymer lower receiver body having a buffer tube collar, a pistol grip attachment point, and a plurality of holes and recesses configured to receive and function with a plurality of operational components for a lower receiver assembly, said insert body being molded or at least partially embedded within a portion of said receiver body such that said screw threads are exposed.

14. The threaded insert of claim 13, wherein said portion of a polymer lower receiver is said buffer tube collar or said pistol grip attachment point.

15. The threaded insert of claim 13, wherein said threaded insert is configured for releasable connection with a buffer tube or a pistol grip retaining screw.

16. The threaded insert of claim 13, wherein said threaded insert does not obstruct or inhibit the use or function of said plurality of holes and recesses.

17. A lightweight, hybrid lower receiver for a firearm, comprising: (a) a polymer lower receiver body having a buffer tube collar, a pistol grip attachment point, and a plurality of holes and recesses configured to receive and function with a plurality of operational components for a lower receiver assembly; and (b) at least one threaded insert sized and shaped to be at least partially embedded within a portion of said polymer lower receiver body, said threaded insert comprising: (1) an aperture extending linearly through at least a portion of said insert; (2) screw threads for releasable connection with a traditionally threaded component of a receiver assembly for said firearm; and (3) an exterior circumference with one or more textural features configured to interface with and retain a polymer; wherein said at least one threaded insert is at least partially embedded or integrally molded within a portion of said polymer lower receiver body such that said portion is reinforced by said threaded insert and said screw threads are exposed for use.

18. The hybrid lower receiver of claim 17, wherein said receiver comprises a first and a second threaded insert, said first threaded insert configured for releasable connection with a buffer tube and at least partially embedded within said buffer tube collar, said second threaded insert configured for releasable connection with a pistol grip retaining screw and at least partially embedded within said pistol grip attachment point.

19. The threaded insert of claim 18, wherein said hybrid receiver weighs between approximately 5.0 to 7.5 ounces.

20. A method of using a threaded insert to form a hybrid lower receiver, comprising: (a) providing a threaded insert for a polymer lower receiver of a firearm; (b) positioning said insert in an injection mold for a polymer lower receiver body having a buffer tube collar, a pistol grip attachment point, and a plurality of holes and recesses configured to receive and function with a plurality of operational components for a lower receiver assembly, said mold configured to accept metallic components; and (c) injecting polymer into the mold under high pressure.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0017] FIGS. 1A and 1B are right and left side elevations, respectively, of an assembled prior art AR-15 rifle;

[0018] FIGS. 2A and 2B are right and left side elevations, respectively, of a typical prior art AR-15 type lower receiver assembly;

[0019] FIG. 3 is a perspective view of one embodiment of a threaded metal insert disclosed herein;

[0020] FIG. 4 is a left side partial cutaway elevation of one embodiment of a stripped hybrid polymer lower receiver disclosed herein showing the threaded metal insert of FIG. 3 as well as a second threaded metal insert of another embodiment embedded therein;

[0021] FIG. 5 is a right side perspective view of the stripped hybrid polymer lower receiver of FIG. 4;

[0022] FIG. 6 is a rear perspective view of the hybrid lower receiver of FIG. 4 showing a pistol grip retaining screw protruding from the second threaded metal insert;

[0023] FIG. 7 is a rear perspective detail view of another hybrid polymer lower receiver showing the pistol grip attachment point with an alternate embodiment of a threaded metal insert embedded therein; and

[0024] FIG. 8 is a cross section detail view of the buffer tube collar of one embodiment of a hybrid polymer lower receiver disclosed herein.

DETAILED DESCRIPTION

[0025] The present disclosure provides threaded metal inserts for use in polymer lower receivers for semi-automatic firearms as well as hybrid polymer and metal lower receiver bodies (i.e., stripped lower receivers) comprising one or more such threaded metal inserts and kits and methods therefor. Hybrid polymer lower receivers constructed in accordance with the present disclosure comprise one or more threaded metal inserts integrally embedded or injection molded within a suitably strong, corrosion resistant synthetic material such as a high-impact, reinforced polymer used to form the lower receiver body. Briefly stated, the threaded metal inserts and hybrid polymer lower receiver bodies disclosed herein provide users with stronger, more durable, inexpensive and lighter weight stripped lower receivers for AR type firearms, such as the AR-15 and AR-10 rifles, than are currently available.

[0026] Turning now to the drawings, where like reference numbers refer to like elements, there is illustrated in FIGS. 1A and 1B each side of a typical AR-15 rifle 10. The words “front,” or “distal” correspond to the firing direction the assembled firearm 10 is facing in FIGS. 1A and 1B (i.e., to the right as shown in FIG. 1A). The words “rear,” “proximal” or “back” correspond to the direction opposite the firing direction of the assembled firearm 10 (i.e., to the left as shown in FIG. 1A). The firearm 10 includes a buttstock 20 connected to a receiver 30 comprised of two separable structural pieces known in the art as an upper receiver 40 and a lower receiver 50. The receiver 30 is connected to a barrel hand guard 25. A pistol grip 70 is located rear of a trigger 80. The lower receiver 50 includes a magazine well 60 that interfaces with a magazine of ammunition 65. The magazine 65 is removable by depressing a magazine release button 66 installed on the lower receiver 50 and stripping or pulling the magazine 65 out of the magazine well 60. The receiver 30 also houses a charging handle 45, which is used to charge a bolt (not shown). A bolt-catch 47 is used to lock a bolt in a rearward open position. The bolt-catch 47 is also activated to release the bolt into a firing position and is therefore sometimes referred to as a bolt release mechanism or button. Unless otherwise noted, the various components which make up the trigger, buttstock, bolt carrier, and barrel assemblies are as those found on the prior art AR type rifles and their various embodiments.

[0027] Referring now to FIGS. 2A and 2B, there are depicted side elevations of a typical prior art AR-15 type lower receiver assembly. The lower receiver assembly comprises a lower receiver body 50 having a trigger guard 85, a magazine well 60, and a buffer tube collar 55. The lower receiver assembly further comprises a buffer tube 21, a collapsible stock 20 and a pistol grip 70 attached to the lower receiver body 50, as well as a safety selector lever 51, a rear take down pin 52, a pivot pin (also known as a “forward take down pin”) 53, a hammer pin 54, a trigger pin 56, a bolt-catch 47, a magazine release button 66 and a magazine catch 67 installed therein. The stock 20 may be of any suitable design, including but not limited to fixed, collapsible, or retractable. In some embodiments, the stock 20 or trigger guard 85 or both may be absent. Additionally, the magazine well 60 may be straight sided or have a flare or chamfer about the exterior opening to facilitate insertion of a magazine. The stock 20 is attached to the lower receiver 50 at the receiver extension housing 55 via a receiver extension (also interchangeable known as a “buffer tube”) 21. A receiver extension or buffer tube 21 is well known in the art and is a generally cylindrical hollow tube configured with screw threads 22 to connectively interface with complimentary threads disposed in the interior of the buffer tube collar 55. In some embodiments, the screw threads 22 are commercial specification (“comm-spec”) threads. In other embodiments, the screw threads 22 are military specification (“mil-spec”) threads. The buffer tube 21 is secured in position in buffer tube collar 55 of the lower receiver 50 by a locking nut (also known as a “castle nut”) 23 and a receiver plate 24.

[0028] Referring now to FIG. 3, there is shown one embodiment of a threaded metal insert 90 constructed in accordance with an aspect of the present disclosure. Generally, a threaded metal insert 90 is a ring-shaped, cylindrical or otherwise generally rounded member (an insert body) having a vacant, substantially circular or tubular aperture configured with screw threads 93 to receive and connectively yet removably interface with a separate traditionally threaded firearm component such as a buffer tube or a pistol grip screw. The aperture extends linearly through at least a portion of an insert body from a surface thereof. However, in some embodiments, the aperture may extend completely through an insert. The inserts disclosed herein are designed to be embedded within a polymer lower receiver so that the threads on the interior of the aperture remain exposed for use even though the rest of the insert may be otherwise completely embedded within or covered by polymer.

[0029] It is to be understood that the inserts disclosed herein can take any overall shape so long as at least a portion of an insert body is contoured to be integrally embedded within a portion of a lower receiver in a way that does not interfere with proper operation of the assembled firearm. Inserts may also be shaped or contoured to generally resemble or fit inside the portion of a lower receiver in which they are integrally embedded or molded. Inserts can also generally be contoured to maintain or reinforce the structural integrity of the portion of a polymer lower receiver in which they are embedded from the high stresses placed upon the receiver by normal use. In some embodiments, the inserts are sized and contoured to be at least partially embedded within a traditionally threaded portion of a polymer lower receiver for an AR type firearm such as the buffer tube collar 55 or the pistol grip attachment point 75. For example, as illustrated in FIG. 3, an insert 90 can take the shape of a generally circular ring having an interior surface configured with screw threads 93. Alternatively, as illustrated in FIG. 7, a threaded insert 95 may have a generally cylindrical shape. Additionally, a threaded metal insert can have a generally ovoid, polyhedron or other symmetrical shape, or an irregular shape (not pictured). Furthermore, a threaded insert 90 can be completely embedded within a portion of a polymer lower receiver so that only the interior threads 93 of the insert 90 remain exposed, as shown in FIGS. 5-6, or only partially embedded in polymer so that the interior threads 98 as well as portions of the insert's exterior surface 97 remain exposed, as shown in FIG. 7.

[0030] The interior of the aperture is configured with screw threads complimentary to the threads on a typical prior art buffer tube or pistol grip screw. Put differently, screw threads are disposed on the interior surface of an insert. In some embodiments, the threads are comm-spec threads. In other embodiments, the threads are mil-spec threads. Although the exterior diameter of a threaded metal insert may generally range from approximately 0.30 to 1.50 inches, according to the particular lower receiver body it is intended to be embedded within, the diameter of the substantially circular aperture (i.e., the “interior diameter”) can range from approximately 0.20 to 1.18 inches.

[0031] In some embodiments, the exterior diameter of a threaded insert can be approximately 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.40, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.50 inches or more. In other embodiments, the exterior diameter of a threaded insert can be approximately 1.15, 1.16, 1.17, 1.18, 1.19, 1.20, 1.21, 1.22, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29, 1.30, 1.31, 1.32, 1.33, 1.35, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41, 1.42, 1.43, 1.44, 1.45, 1.46, 1.47, 1.48, 1.49, 1.50 inches or more. In certain embodiments, the exterior diameter is approximately 1.30, 1.31, 1.32 or 1.33 inches. In additional embodiments, the exterior diameter is approximately 0.34 or 0.35 inches.

[0032] In some embodiments, the interior diameter of a threaded insert can be approximately 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33 inches or more. In certain embodiments, the interior diameter is 0.240, 0.241, 0.242, 0.243, 0.244, 0.245, 0.246, 0.247, 0.248, 0.249, 0.250, 0.251, 0.252, 0.253, 0.254, 0.255, 0.256, 0.257, 0.258, 0.259 or 0.260 inches. In one embodiment, the interior diameter is approximately 0.248 inches. In other embodiments, the interior diameter of a threaded insert can be approximately 0.90, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1.00, 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, 1.20 inches or more. In certain embodiments, the interior diameter is 1.141, 1.142, 1.143, 1.144, 1.145, 1.146, 1.147, 1.148, 1.149, 1.150, 1.151, 1.152, 1.153, 1.154, 1.155, 1.156, 1.157, 1.158, 1.159, 1.160, 1.161, 1.162, 1.163, 1.164, 1.165, 1.166, 1.167, 1.168, 1.169, 1.170, 1.171, 1.172, 1.173, 1.174, 1.175, 1.176, 1.177, 1.178, 1.179, 1.180, 1.181, 1.182, 1.183, 1.184, 1.185, or 1.186 inches. In one embodiment, the interior diameter is approximately 1.00 inches.

[0033] A threaded insert can be made of any metal or metallic material suitable for use in a firearm. More pointedly, the inserts disclosed herein can be made from any suitably tough metal or metallic material having sufficient strength and durability to withstand sustained contact with the screw threads of a typical metal buffer tube or a metal pistol grip screw during repeated discharge of an AR type firearm. In some embodiments, the metal or metallic material is marine grade brass, steel, aluminum, anodized aluminum, cast zinc, titanium, brass, copper, or a metallic alloy. Use of the foregoing materials to form threaded inserts in the disclosed shapes results in a light weight insert which advantageously does not significantly or substantially affect the weight of a hybrid polymer lower receiver comprising such an insert. A threaded metal insert constructed in accordance with the present disclosure can weigh approximately 3 to 20 grams. In some embodiments, a threaded metal insert for a pistol grip screw attachment point weighs approximately 4 to 8 grams. In other embodiments, a threaded metal insert for a buffer tube collar weighs approximately 12 to 19 grams. In certain embodiments, a threaded insert can weigh approximately 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0, 12.5, 13.0, 13.5, 14.0, 14.5, 15.0, 15.5, 16.0, 16.5, 17.0, 17.5, 18.0, 18.5, 19.0, 19.5 or 20.0 grams or more.

[0034] Referring again to FIG. 3, a threaded insert can further include one or more textural features that impart texture to the exterior surface of the insert and which aid in making the insert integral to the hybrid polymer lower receiver body. Appropriate exterior surface textural features are those which are not easily broken or worn off and which can interface with and hold polymer during the molding process to permanently embed the insert in the polymer. Such textural features are designed make the insert irremovable from the polymer lower receiver body under normal use. For example, suitable textural features include, but are not limited to, relief channels or cuts, notches, divots, depressions, knurling, cross hatching, shallow holes or pits, or other similar features which impart texture to the exterior surface so that polymer may gain purchase on the insert during the molding process. In one embodiment shown, the exterior surface of an insert 90 is configured with an expanse of diamond knurling 92 bounded by two opposing parallel relief channels 91. In another embodiment shown in FIG. 7, the exterior surface of the insert 95 is configured with knurling 97 and a cut-out or notch 99. The use of textural features on the exterior surface of threaded inserts strengthens the completed hybrid polymer lower receiver body and decreases the number of potential failure points by reducing the chances that a threaded insert will pull out of a receiver under normal use and conditions. Moreover, as shown in FIGS. 3 and 7, respectively, the relief cuts 91 and the notch 99 are disposed on the exterior surface of the inserts at a substantially perpendicular angle to the direction in which a separate threaded component, such as a buffer tube or pistol grip screw, would be inserted and removed. The orientation of these textural surface features further protects the inserts from being pulled out of the polymer by creating a ticker layer or ribbon of polymer between the inserts and the direction of the mostly likely source of outward-pulling stress.

[0035] Referring now to FIGS. 4-6, there is illustrated one embodiment of a hybrid polymer lower receiver 50 constructed in accordance with an aspect of the disclosure. A hybrid lower receiver 50 is generally a stripped polymer lower receiver for an AR type firearm, such as an AR-15 rifle, having one or more threaded metal inserts of the present disclosure at least partially embedded therein. For example, the hybrid polymer lower receiver may include a first threaded insert, which may be threaded to receive a buffer tube (a “buffer tube insert”). The hybrid polymer lower receiver may also or alternatively include a second threaded insert, which may be threaded to receive a pistol grip retaining screw (a “pistol grip insert”). In some embodiments, the hybrid lower receiver 50 can include a buffer tube insert 90 embedded in the buffer tube collar 55. In other embodiments, the hybrid lower receiver 50 can include a pistol grip insert 95 embedded in the pistol grip attachment point 75. In the embodiment shown in FIGS. 4-6, the hybrid polymer receiver comprises a stripped polymer lower receiver for an AR type firearm having a buffer tube insert 90 and a pistol grip insert 95 completely embedded in the buffer tube collar 55 and the pistol grip attachment point 75, respectively, so that only the internal threads are exposed. Specifically, as shown in FIG. 6, only the internal threads 93 on the interior surface of the buffer tube insert 90 are exposed for engagement with a buffer tube (not pictured), while the internal threads of the pistol grip insert 95 are depicted as engaged by a pistol grip screw 71. Notably, the threaded metal inserts 90, 95 do not inhibit or obstruct access, use or function of the receiver plate recess 94, the takedown pin spring and detent recess 96, or any of the other various recesses, holes and grooves in the lower receiver body 50 designed to receive the operational components of a typical lower receiver assembly for an AR type firearm, such as those depicted in FIGS. 1-2. The threaded metal inserts disclosed herein are suitable for use in polymer lower receivers for AR type firearms in any caliber, including but not limited to .223 and .308 WINCHESTER, as well as their NATO equivalents.

[0036] Referring again to FIG. 4, the cutaway portions of the buffer tube collar 55 and pistol grip attachment point 75 illustrate how the textural features on the exterior surface of the buffer tube insert 90 and pistol grip insert 95 interface with and are molded into the polymer material forming the lower receiver body 50. Specifically, the polymer forming the buffer tube collar 55 fills the channel cuts 91 and diamond knurling 92 on the exterior surface of the buffer tube insert 90, while the polymer forming the pistol grip attachment point 75 likewise fills the knurling on the exterior surface of the pistol grip insert 95. In this way, the two inserts 90, 95 are made permanently integral to and irremovable from the buffer tube collar 55 and pistol grip attachment point 75, respectively. Although the hybrid polymer lower receiver 50 is illustrated and described as having first and second threaded metal inserts 90, 95 embedded therein, it is to be understood that a hybrid polymer receiver 50 may have only one threaded metal insert embedded therein, for example, in either the buffer tube collar 55 or the pistol grip attachment point 75. For example, in one embodiment (not shown), a hybrid polymer lower receiver 50 includes a threaded metal insert at least partially embedded within the buffer tube collar 55, but no second insert embedded within the pistol grip attachment point 75. It should be noted, however, that the use of two threaded metal inserts, as opposed to one, does not significantly impact the overall weight of a hybrid polymer lower receiver. For example, a hybrid polymer and metal lower receiver body constructed in accordance with the present disclosure can weigh less than 10 ounces. In some embodiments, the stripped hybrid receiver weighs less than 8.0 ounces. In certain embodiments, a stripped hybrid receiver comprising two threaded metal inserts disclosed herein weighs approximately 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9 or 8.0 ounces.

[0037] Referring now to FIG. 7, there is illustrated a rear perspective detail view of another embodiment of a hybrid polymer lower receiver 50. The pistol grip attachment point 75 rearward of the trigger guard 85 includes an alternate embodiment of a threaded metal insert 95 partially embedded therein. The interior threads 98 are exposed and configured to receive a pistol grip screw (such as the screw identified in FIG. 6 by the numeral 71). The exterior surface of the insert 95 includes two textural features—knurling 97 and a notch 99—both of which are partially exposed through the polymer. The notch 99 is filled with polymer that bisects the exposed knurling 97 into two sections. As noted above, the notch 99 is perpendicular to the direction of stress encountered during normal use and reduces the likelihood that the insert 95 will pull out from the pistol grip attachment point 75 by providing a stronger point of contact between the insert 95 and the polymer than knurling 97 alone. It is to be understood that although the insert 95 is depicted as being generally cylindrical and partially embedded within the polymer, the insert 95 could be fully embedded within the pistol grip attachment point 75 or take any other shape suitable to accept a pistol grip screw 71 but not interfere with the attachment of a pistol grip.

[0038] Referring now to FIG. 8, there is illustrated a cross sectional detail view of another embodiment of a hybrid polymer lower receiver 50 showing a buffer tube insert 90 embedded within the buffer tube collar 55. The insert 90 is completely embedded within the buffer tube collar 55; only the interior threads 93 are exposed. The insert 90 comprises two relief channels 91 and knurling 92 on the exterior surface. The relief channels 91 and knurling 92 are visibly filled with polymer near the top and bottom of the buffer tube collar 55. The threaded metal insert 90 does not overlap or obstruct either the receiver plate recess 94 in the rear of the lower receiver body or the buffer retainer and buffer retainer spring recess 99 in the rear of the central cavity of the receiver body. Although the buffer tube insert 90 shown in FIG. 8 is depicted as a generally circular ring, it is to be understood that alternate embodiments of the insert 90 may take a different shape. For example, in some embodiments, the insert 90 may be an irregular polygonal or ovoid shape and overlap one or more of the receiver plate recess 94 and buffer retainer and buffer retainer spring recess 99. However, in such embodiments, the insert 90 may be embedded with a larger portion of the rear of the receiver body and may weigh more than a smaller ring-shaped insert. Such inserts may further comprise one or more cavities, holes or recesses having a shape and size suitable to allow a separate receiver plate or buffer retainer and buffer retainer spring to pass through the insert and function normally. Other larger or asymmetrically-shaped threaded inserts constructed in accordance with aspects of the present disclosure that are designed to be embedded within or cover other or larger areas of the lower receiver body may similarly comprise one or more cavities, holes or recesses positioned to allow the insertion of one or more operational components designed to interface with a corresponding cavity, hole or recess otherwise blocked by a portion of the insert.

[0039] Accordingly, in accordance with another aspect of the present disclosure, there are also disclosed herein hybrid polymer and metal lower receiver assembly kits comprising a stripped hybrid polymer lower receiver having one or more threaded metal inserts at least partially embedded therein, and the operational components of a lower receiver parts kit. In one embodiment, a hybrid polymer and metal lower receiver assembly kit comprises a stripped hybrid polymer lower receiver having one or more threaded metal inserts at least partially embedded therein, and at least one of: a trigger, a hammer, a selector switch, a magazine catch, a bolt catch, a takedown pin, a pivot pin, a spring, a selector detent pin, a takedown detent pin, a pivot pin detent, a trigger pin, a hammer pin, and a trigger disconnect.

[0040] In accordance with yet another aspect of the present disclosure, there is disclosed herein a method of forming a hybrid polymer lower receiver body using one or more threaded metal inserts in conjunction with a molding process. In some embodiments, the method comprises providing one or more threaded metal inserts disclosed herein, inserting said one or more threaded metal inserts into an injection mold designed for the inclusion of metallic inserts, closing the mold around said one or more threaded metal inserts, and injecting polymer into the mold so that said inserts become at least partially embedded therein. The injection mold can be any kind of mold, but in one embodiment, is a high pressure injection mold. High pressure injection causes the polymer to flow around and fill any textural features present on the external surface of said insert or inserts, but not the internal threads. In additional embodiments, said inserts comprise internal threads which remain exposed for use by the end user. In other embodiments, the method may further comprise selecting one or both of an AR style buffer tube and pistol grip screw for use with the hybrid lower receiver, and determining the proper complimentary thread needed for the selected buffer tube or pistol grip screw. Once complete, a user may then insert metal screws into the threaded metal inserts of the hybrid polymer lower receiver with no reduction in receiver longevity.

[0041] It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.

INTERPRETATION

[0042] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0043] The use of the terms “a” and “an” and “the” and similar referents in the context of describing an invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted 1by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., “including, but not limited to,”) unless otherwise noted. Recitation of ranges as values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention (i.e., “such as, but not limited to,”) unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0044] While the disclosure above sets forth the principles of the invention disclosed herein, with examples given for illustration only, those skilled in the art will appreciate from the foregoing that various adaptations and modifications of the just described embodiments can be configured in various respects without departing from the scope and sprit of the invention. The inventors expect that skilled artisans will employ various obvious changes in form and detail, and the inventors intend for the invention to be practiced other than as specifically described herein. Accordingly, the invention includes all equivalents and usual and obvious modifications of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described features and elements in all possible variations hereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. Therefore, it is to be understood that the invention must be measured by the scope of the appended claims and not by the description of the examples or the preferred embodiments.