This invention relates generally to firearms and, more particularly, to an apparatus and method for converting an AR-15 rifle to a bullpup rifle configuration. The apparatus and method involve disassembling parts of the AR-15 firearm and coupling a kit of components, including a bullpup lower receiver and other components, to the disassembled AR-15.
A bullpup firearm rifle is a firearm with its action and magazine behind the trigger—the opposite of traditional rifle firearms. This configuration reduces the length of the firearm by about 25%, includes a more forward trigger, and is typically seen as being more maneuverable than a full-size rifle. A bullpup rifle may also have a shortened or removed butt stock. Many gun enthusiasts have a desire to have a bullpup firearm but find them hard to find to purchase. Alternatively, an existing rifle may be converted to a bullpup but may require complicated and extensive engineering to do so. However, enthusiasts of high-powered weapons may have an AR-15 and would find it desirable if the existing AR-15 could be easily modified into a bullpup configuration.
Therefore, it would be desirable to have a method and kit for disassembling portions of an AR-15 and assembling a bullpup firearm using parts of both the disassembled AR-15 and the bullpup kit.
Therefore, a method for disassembling and converting an AR-15 into the bullpup configuration of an AR-15 firearm assembly includes releasing and removing specific components of the AR-15 and then replacing the removed components with elements from the kit. Specifically, the standard buttstock of the AR-15 is removed and replaced with a bullpup buttstock. Further, the AR-15 bolt carrier group and buffer tube is removed and replaced with a bullpup bolt carrier group and buffer plug. Finally, the AR-15 trigger guard is removed and replaced with a trigger guard plate from the kit and which essentially covers the stock trigger which remains.
Then, additional elements of the bullpup assembly may be coupled to the modified AR-15 assembly. Specifically, the bullpup receiver (or sometimes called the lower receiver) is coupled to the barrel assembly of the modified AR-15 assembly, the bullpup lower receiver including a bullpup trigger portion. Then a trigger linkage is connected between the bullpup trigger portion and AR-15 stock trigger so that pulling the bullpup trigger simultaneously actuates the stock trigger to fire the firearm. The actual AR-15 trigger is hidden behind a pair of trigger guide plates and a side plate. The result is that the AR-15 is converted into a bullpup configuration. The method may be reversed without any damage or modification of the stock components of the unmodified AR-15 firearm.
Therefore, a general object of this invention is to provide a bullpup configuration of an AR-15 firearm assembly and a method for disassembling and converting an AR-15 into the bullpup configuration of an AR-15 firearm assembly.
Other objects and advantages of the present invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, embodiments of this invention.
A bullpup configuration of an AR-15 firearm assembly and a method for converting an AR-15 into the bullpup configuration of an AR-15 firearm assembly will now be described in detail with reference to
The bullpup configuration of a modified AR-15 is shown assembled in
In order to convert a standard configuration AR-15 to the bullpup configuration, certain components of the standard configuration AR-15 must be detached or uncoupled from the components that will remain and receive the components from the bullpup configuration. For instance, the standard AR-15 includes a buttstock 102 coupled to a rear end of an AR-15 body frame 40 (which is the lower receiver of the AR-15). The first step of the method of conversion is to uncouple the AR-15 buttstock 102 and to attach the AR-15 stock 12 in its place. It will be understood that components described may be coupled using pins, screws, or the like. Next, the standard AR-15 includes a trigger guard surrounding and protecting a standard AR-15 trigger 41 and this trigger guard or at least a bottom wall thereof is removed. This standard structure will be replaced by corresponding structures from the bullpup kit 10 as will be explained in greater detail later.
Further, it is desirable to remove the stock AR-15 bolt carrier group that fires and ejects bullets from the AR-15 and to replace it with a bolt carrier group 24 (or “BCG”) and buffer plug from the bullpup kit 10. The bolt carrier group 24 may include a rear charging handle 25 that is operable to load a bullet casing into the chamber to be shot as is known in the art. In the stock AR-15, the bolt carrier group may include a rear charging handle 25 that may be alternately positioned to the rear or to the side of the bolt carrier group. However, the converted bullpup configuration will include a forward charging handle 25a that is positioned forward of the trigger, as will be described below and is shown in
With the stock buttstock, stock trigger guard, and bolt carrier group removed, what is left will be referred to as a modified AR-15 assembly to which all elements of the bullpup kit 10 may be attached in replacement or in addition as described below.
The bullpup kit 10 includes a bullpup lower receiver 14 that provides the primary framework to which other components may be attached or that forms other components. More particularly, the bullpup receiver 14 includes an upper surface 15 (also referred to as the bullpup upper receiver) defining an elongate and generally planar surface that may be coupled to the body frame 40 (AR-15 lower receiver) of the modified AR-15 assembly. It is understood that the upper surface 15 may support a barrel assembly 42 of the modified AR-15 assembly and, more particularly, may include a silencer or sound suppressor coupled or positioned about the barrel. The bullpup receiver 14 may also be referred to as the lower receiver.
The bullpup receiver 14 may include a trigger handle 22 and bullpup trigger 21 (
The bullpup kit 10 may include a bullpup guide plate 18 that may be attached to or integrally constructed with the bullpup trigger 21, the bullpup guide plate 18 defining what will be referred to as a bullpup trigger slot 19 through which a respective connection pin 37 extends. The connection pin 37 moves in the bullpup trigger slot 19 when the bullpup trigger 21 is actuated which causes the trigger linkage 30 to move rearward — actuating the AR-15 trigger 41 to fire the firearm. The standard AR-15 includes a guide plate 44 that is coupled to the body frame 40 and positioned proximate the AR-15 trigger 41 and that defines what will be referred to as an AR-15 guide slot 45 (
The guide plate 18 and a trigger guard 20 essentially sandwich the AR-15 trigger 41 so as to shield it from damage and to prevent inadvertent actuation (
Now described in more detail, the bolt carrier group (BCG) 24 included in the bullpup kit 10 and which replaces the traditional bolt carrier group of the original AR-15 assembly is critical to the proper and superior functionality of the converted assembly of the bullpup configuration. Specifically, the bolt carrier group 24 includes an elongate forward charging handle 25a forward of the bullpup trigger 21 (
The bullpup carrier group 24 includes carrier portion 24a and a spring assembly 50 having a plurality of compression springs 51 each having a distal end 51a seated in a ring-shaped flange referred to as a buffer plug 51c associated with the body frame 40 and a proximal end 51b that interfaces with the carrier portion 21a that slidably recoils to compress the springs 51, e.g., when a bullet is fired. The springs 51 are configured to compress toward the buffer plug 51c when the charging handle 25/charging arm 23 is pulled back and then to push the carrier member 24a forwardly when the charging handle 25 is released (which releases the tension on the springs). It should be noted that the modified AR-15 is able to accommodate and absorb the recoil of the carrier portion 24a without the standard buffer that would conventionally extend into the buttstock.
Now, more particularly, the BCG 24 includes a plurality of guide rods 53 each extending longitudinally from buffer plug 51c forwardly in the direction of the carrier portion 24a. Each spring of said plurality of compression springs 51 are positioned loosely about the plurality of guide rods 53, respectively. While each guide rod 53 has a fixed length, each spring 51 is configured to compress when loaded and to expand/decompress when the load is removed. Further, the carrier portion 24a of the BCM 24 includes a casing having an outer surface that defines a plurality of grooves 55 (which may also be referred to as channels 55), the plurality of grooves 55 being radially spaced apart in a predetermined and perfect alignment with the plurality of guide rods 53. In operation, when the carrier portion 24a is moved rearwardly (such as when the charging arm 23 is pulled rearwardly), whether manually to talk the hammer 54 or when recoiling after firing a bullet, the plurality of guide rods 53 are configured to slide along the plurality of grooves 55, respectively while the associated plurality of springs 51 are compressed. This relationship is best shown in
Operation of the bolt carrier group (BCG) 24 may be described in detail as follows. To initiate operation, the charging handle 25 must be pulled rearwardly towards the stock 12 of the gun in alignment with the barrel. On the top of the BCG 24 there is a shelf which interfaces with the charging arm 23. Pulling the charging handle 25 rearwardly (using the forward 25a or rearward 25 handle), pulls the charging arm 23 rearwardly which pushes the carrier portion 24a rearwardly due to the interface between the charging arm 23 and carrier portion 24a. As the carrier portion 24a moves rearwardly, the coils of the buffer spring 51 are pulled into tension/compressed (
In another aspect and as shown in
Using the bullpup kit 10, a conventional AR-15 firearm 100 may be converted to a bullpup configuration. Specifically, the AR-15 firearm 100 is, in part, disassembled and such that components from the bullpup kit 10 may then be mounted to the AR-15 frame 40 that remains as described above. The method may be selectively reversed to return to the conventional AR-15 firearm 100 configuration—all without making any permanent modifications to the components of either assembly.
It is understood that while certain forms of this invention have been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims and allowable functional equivalents thereof.
REFERENCE TO RELATED APPLICATIONS This application is related to U.S. 63/281,967 filed on Nov. 22, 2021 titled Method and Apparatus for Converting an AR-15 Firearm into a Bullpup Configuration, which is incorporated by reference in its entirety.
Number | Date | Country | |
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Parent | 63281967 | Nov 2021 | US |
Child | 17732861 | US |