Tubular magazine firearm with sheet metal receiver

Abstract

A novel firearm is lightweight, compact, and the method of manufacture is easy. A single or dual tubular magazine positioned below the barrel of a firearm includes the novel use of an inverted U-shaped stamped receiver cover with a cavity for housing a loading and ejection port. The present invention advances the art of firearm manufacture by disclosing a tubular magazine and stamped sheet metal receiver cover that encloses the major parts of a firearm. The firearm is simple to manufacture, lightweight, approximately 25 to approximately 27 inches in length, and affords an ammunition capacity that is at least twice the capacity of a comparable firearm, such as the Remington 870 shotgun.

Claims

1. A tubular magazine firearm, comprising: an assembly of at least one tubular magazine for ammunition positioned below a barrel with a barrel extension at a rear of the barrel; a stock with a lifter and a rear end; a pistol grip; and a receiver between the grip and the stock rear end with an inside cavity housing the lifter forming a loading and ejection port, the receiver including a front end attachable to a rear end of the grip and a rear end attachable to the stock rear end wherein the receiver partially encloses, fastens and securely holds the stock, the grip and the assembly of magazine and barrel with barrel extension thereby forming an assembled tubular magazine firearm, wherein the receiver includes an attached trunion for rigidity.

2. The firearm of claim 1, wherein the receiver includes: an inverted U-shaped sheet metal receiver with an inside cavity.

3. The firearm of claim 1, wherein the lifter includes: a U-shaped lifter open at the far end including a left and a right arm lifter that rotate on an axis at the attached rear ends of the left and right arm lifters to lift a shell into a position to be fed into a chamber of a firearm and aid in expelling a spent shell from the chamber, the U-shaped lifter positioned between the grip rear end and the stock front end within the cavity of the receiver to form a downward ejection port for the spent shell.

4. The firearm of claim 1, wherein the assembly includes a first tubular magazine and a second tubular magazine positioned below the barrel with the barrel extension at the rear of the barrel.

5. The firearm of claim 1, wherein the barrel has a sight base for mounting a picatinny rail.

6. The firearm of claim 1, wherein the receiver is fastened over the stock, and the loading and ejection port rearward of the grip and the assembly of magazine and barrel with barrel extension.

7. The firearm of claim 1, wherein the receiver is integrally formed with a left front rectangular shaped tab and an opposing and matching right front rectangular shaped tab for attaching the trunnion.

8. The firearm of claim 7, wherein the receiver is integrally formed with a left rear triangular shaped tab and an opposing and matching right rear triangular-shaped tab for attaching the stock and the rear end of the grip, the space between the left and right front tabs and the left and right rear tab forming the loading a ejection port cavity.

9. The firearm of claim 1, wherein the overall length is between approximately 25 inches and approximately 27 inches.

10. A tubular magazine firearm, comprising: an assembly of at least one tubular magazine for ammunition positioned below a barrel with a barrel extension at a rear of the barrel; a stock with a lifter and a rear end; a pistol grip; and a receiver between the grip and the stock rear end with an inside cavity housing the lifter forming a loading and ejection port, the receiver including a front end attachable to a rear end of the grip and a rear end attachable to the stock rear end wherein the receiver partially encloses, fastens and securely holds the stock, the grip and the assembly of magazine and barrel with barrel extension thereby forming an assembled tubular magazine firearm, wherein the receiver includes: an inverted U-shaped sheet metal receiver with an inside cavity, and wherein the loading and ejection port assembly further comprises: a frame on the rearward pistol grip; and a captor spring that forms an assembly push pin that is inserted into the front pin, an upward rotation of the U-shaped lifter lifts a shell into position to be fed into firing chamber and a downward rotation of the U-shaped lifter aids in expelling a spent shell from the firing chamber.

11. The firearm of claim 8, further comprising: a front frame pin insertable into a left and right hole in each of the left and right front tabs respectively; and a rear frame pin insertable into a left and right hole in each of the left and right rear tabs respectively, the front and rear frame pins allow rapid assembly and disassembly of the firearm.

12. The firearm of claim 8, wherein the receiver further includes a trunnion connected between the left and right front rectangular shaped tabs for rigidity, the trunnion with a left side and right side hole aligned for insertion of the front frame pin through the left front tab, the trunnion and the right front tab.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) Referring particularly to the drawings for the purposes of illustration only, and not limitation:

(2) FIG. 1 is a perspective view of a fully assembled firearm of the present invention with an inverted U-shaped sheet metal receiver enclosing a hollow stock and attached grip.

(3) FIG. 2 is a perspective view of the firearm of the present invention with the forend removed.

(4) FIG. 3 is an exploded perspective view of the firearm receiver portion separated from the grip portion thereof.

(5) FIG. 4 is an exploded perspective view of the hollow stock of the firearm separated from the receiver portion enclosing dual tubular magazines and gun barrel.

(6) FIG. 5 is an exploded view of the fun barrel separated from the dual tubular magazines enclosed by an inverted U-shaped sheet metal receiver.

(7) FIG. 6 is an enlarged perspective view of the dual tubular magazines enclosed by an inverted U-shaped sheet metal receiver.

(8) FIG. 7 is an enlarged exploded view of dual tubular magazines separated from the inverted U-shaped sheet metal receiver and a trunion.

(9) FIG. 8 is an enlarged exploded view of the inverted U-shaped sheet metal receiver separated from the stabilizing trunnion

(10) FIG. 9 is an enlarged perspective view of the barrel of the firearm of the present invention with a barrel extension, sight base for mounting the Picatinny Rail, and muzzle plate at the forward end.

(11) FIG. 10 is an enlarged perspective view of the grip with a loading and ejection port and a trigger.

(12) FIG. 11 is a perspective view of the stock showing the lifter that assists in loading shells and aiding in the ejection of spent shells.

DESCRIPTION OF THE PREFERRED EMBODIMENT

(13) Before explaining the disclosed embodiment of the present invention in detail, it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.

(14) It would be useful to discuss the meanings of some words used herein and their application before discussing the dual tubular firearm of the present invention with an inverted U-shaped sheet metal receiver enclosing a hollow stock and attached grip and method of using the same.

(15) Ammunition, cartridge and shell are used interchangeably to mean a cylindrical, usually metal casing containing the primer and powder charge or bullet for a firearm.

(16) Firearm is used herein to refer to all weapons to which a tubular magazine, barrel and stock can be enclosed in an inverted U-shaped sheet metal receiver. A preferred weapon for attaching the present invention is a shotgun.

(17) The directional terms horizontal, vertical, front, forward, rear, rearward, right, and left refer to the firearm when held in the normal firing position. When firing, the rear end of the firearm is close to or in close proximity to the body of the user, while the front end is farthest from the user and the point at which the ammunition exits the firearm.

(18) KSG is used herein to refer to Kel-tech Shot Gun, a firearm of the present invention.

(19) Kevlar is a registered trademark of the DuPont Company for a para-aramid synthetic fiber.

(20) The picatinny rail is a bracket used on some firearms in order to provide a standardized mounting platform. Its name comes from the Picatinny Arsenal in New Jersey, USA where it was originally tested.

(21) Remington Model 870 is a U.S.-made pump-action shotgun manufactured by Remington Arms Company, Inc. Remington is a registered trademark of RA Brands LLC.

(22) Tubular magazine is used herein to include any gauge or size of ammunition and is not limited to any particular gauge of ammunition.

(23) Listed below are the components of the dual tubular firearm with an inverted U-shaped sheet metal receiver shown in FIGS. 1-11. 10 Stock, sometimes referred to as hollow stock because it houses moving parts. 12a Captor spring is used to form the assembly push pin. 12b Frame pin receives the captor spring as one of the assembly pins holding the firearm together. 14 Loading and Ejection Port 15 Lifter, a rigid U shaped steel part that rotates on an axis to lift shells into a position to be fed into the chamber and aid in expelling the spent shell from the chamber. 15a A right arm of the Lifter 15b A left arm of the Lifter 16 Grip 18 Trigger 20 Forend provides pump action 22 A first tubular magazine 24 A second tubular magazine 26 Barrel of firearm 28 Muzzle plate joins the barrel, magazine tubes and Picatinny rail together as a unit and also provides two sling attachment points. 29 Sight base, provides the mounting point for the Picatinny rail to hold sights and other accessories for the firearm. 30 Barrel extension of firearm is threaded onto the rear of the barrel. 40 Inverted U-shaped sheet metal receiver 45 Inside cavity of U-shaped sheet metal receiver that houses the loading and ejection port 50 Rectangular shaped left front tab on inverted U-shaped sheet metal receiver 51 Hole in left front tab for a frame pin to ride through 52 Notch in left front tab to provide clearance for the selector catch axis which secures the selector catch, so when the trunnion is welded to the receiver, the selector catch axis can still be inserted and removed. 53 Rectangular shaped right front tab on inverted U-shaped sheet metal receiver 54 Hole in right front tab for a frame pin to ride through 55 Notch in right front tab to provide clearance for the selector catch axis which secures the selector catch, so when the trunnion is welded to the receiver, the selector catch axis can still be inserted and removed. 60 Triangular shaped left rear tab on inverted U-shaped sheet metal receiver 61 Hole in left rear tab for a frame pin to ride through 62 Triangular shaped right rear tab on inverted U-shaped sheet metal receiver 63 Hole in right rear tab on inverted U-shaped sheet metal receiver 65 Position for spot welding the inverted U-shaped sheet metal receiver to the firearm parts housed within the inside cavity 70 Trunnion 71 Left side of trunnion 72 Left hole aligns with notches 52 and 55 to provide clearance for the selector catch axis which secures the selector catch 73 Left hole aligns with holes 51 and 54 for a frame pin to ride through 74 Left hole is for a dowel pin to be inserted which secures the cartridge stops 75 Right side of trunnion 76 Right hole aligns with notches 52 and 55 to provide clearance for the selector catch axis which secures the selector catch 77 Right hole aligns with holes 51 and 54 for a frame pin to ride through 78 Right hole is for a dowel pin to be inserted which secures the cartridge stops 79 Cross piece attaching left side to right side of trunnion

(24) In general, the operation of the tubular firearm with an inverted U-shaped sheet metal receiver of the present invention includes the use of a tubular magazine, preferably, dual tubular magazines, barrel with barrel extension threaded onto the rear of the barrel, stock with lifter, wherein the lifter is a rigid U-shaped steel part that rotates on an axis to lift shells into position to be fed into the firing chamber. On the downward rotation, the lifter also serves as the ejector, which aids in expelling the spent shell from the chamber.

(25) The inventive feature of the present invention consists of providing an inverted U-shaped stamped sheet metal receiver enclosing a hollow stock and attached grip. The inverted U-shaped sheet metal receiver affords the advantages of producing a firearm that is easy to manufacture, of lower weight, and smaller size with an increased ammunition capacity. For example, Table I below compares the firearm of the present invention, identified by the acronym KSG, with a comparable firearm, the Remington 870.

(26) TABLE-US-00001 TABLE I Size and Weight Comparison of Firearms Specification KSG Reminztone 870 Barrel length 18.5 inches 18 inches Overall length 26.1 inches 38.5 inches Chamber 3 inches 3 inches Magazine capacity 6 + 6 + 1 (shells) 4 + 1 (shells) Total weight 6.9 pounds 7.25 pounds
The firearm of the present invention has a smaller footprint, is lighter in weight and can carry more than twice the amount of ammunition, 13 shells for KSG versus 5 shells for the Remington 870.

(27) Referring now to the Figures, although FIGS. 1-7 herein are drawn to show a dual tubular magazine, a single or dual tubular magazine is contemplated and considered within the scope of the present invention.

(28) FIG. 1 is a perspective view of a fully assembled firearm of the present invention. FIG. 1 shows the major units of the firearm secured and held in place by an inverted U-shaped stamped sheet metal receiver 40. The assembled parts shown are the stock 10 with a lifter 15 having a right arm 15a and a left arm 15b (not shown in FIG. 1). Also shown is grip 16 with loading and ejection port 14 and trigger 18, positioned below and adjacent to the stock 10.

(29) In addition, the major parts include a first tubular magazine 22, a second tubular magazine 24, and a barrel extension 30 (shown in FIGS. 5 and 9) threaded on the rear of the barrel 26. All of the major parts are enclosed and partially covered by an inverted U-shaped sheet metal receiver 40 that fastens and holds the assembled parts in place with strategic spot welding, a captor spring 12a that forms an assembly push pin that is inserted into a frame pin 12b thereby securing the assembled parts at the rear end of the firearm in a stable manner.

(30) At the front end of the gun, the barrel 26, first tubular magazine 22 and second tubular magazine 24 are secured and held in place with a muzzle plate 28. A forend 20 is movably attached to provide the pumping action required for firing the firearm.

(31) FIG. 2 is a perspective view of the firearm with the forend 20 removed, thus showing how the first tubular magazine 22, second tubular magazine 24 and barrel 26 are secured and held in place with a muzzle plate 28. Also shown in FIG. 2 is the sight base 29 that provides a mounting point for the Picatinny rail.

(32) FIG. 3 is an exploded view of the firearm receiver portion with stock 10, the first tubular magazine 22, second tubular magazine 24 and barrel 26 are secured and held in place with a muzzle plate 28 at the front end of the firearm and partially covered by the inverted U-shaped sheet metal receiver 40 at the rear end of the firearm. In FIG. 3, the grip portion including captor spring 12a that forms an assembly push pin that is inserted into a frame pin 12b, loading and ejection port 14, grip 16 and trigger 18, are shown apart from the receiver portion.

(33) FIG. 4 is an exploded perspective view of the stock 10 with lifter 15 having a right arm 15a and a left arm 15b separated from the inverted U-shaped sheet metal receiver 40 that encloses or partially covers a first tubular magazine 22, a second tubular magazine 24, and a barrel extension 30 (shown in FIGS. 5 and 9) threaded on the rear of the barrel 26. At the front end of the assembly, the barrel 26, first tubular magazine 22 and second tubular magazine 24 are secured and held in place with a muzzle plate 28. Also shown in FIG. 4 is the sight base 29 that provides a mounting point for the Picatinny rail.

(34) FIG. 5 is an exploded view of the muzzle plate 28 on the front of barrel 26 which has a sight base 29, and barrel extension 30 threaded onto the base of the barrel 26. The barrel assembly is separated from a first tubular magazine 22, a second tubular magazine 24 that are partially covered by the inverted U-shaped sheet metal receiver 40 with a loading and ejection port 14 cavity.

(35) FIG. 6 is an enlarged perspective view of the dual tubular magazines 22, 24 partially enclosed or partially covered by the inverted U-shaped sheet metal receiver 40 with a loading and ejection port 14 cavity.

(36) FIG. 7 is an enlarged exploded view of the dual tubular magazines removed from the inverted U-shaped sheet metal receiver 40 with a loading and ejection port 14 cavity. Also shown in FIG. 7 is a trunnion 70 that is optionally welded below the magazines for added rigidity.

(37) FIG. 8 is an enlarged exploded view of the inverted U-shaped sheet metal receiver 40 separated from the stabilizing trunnion 70. In FIG. 8, the holes and notches in the tabs 50, 53, 60 and 62 at the bottom of the inverted U-shaped sheet metal receiver provide clearance for pins to be inserted. More specifically, in rectangular-shaped tabs 50 and 53, holes 51 and 54 align for a first frame pin to be inserted. Likewise, in triangular-shaped tabs 60 and 62, holes 61 and 63 are for a second frame pin to be inserted. There are two frame pins in the firearm used for rapid disassembly of the major components of the firearm.

(38) Notches 52 and 55 in rectangular-shaped tabs 50 and 53 align for the selector catch axis to be inserted which secures the selector catch. When the trunnion 70 is welded to the receiver the selector catch axis can still be inserted and/or removed.

(39) The inverted U-shaped sheet metal receiver 40 is designed as a one-piece unit constructed of sheet metal. The metal used is selected from all steels, including, but not limited to, stainless steel, high strength aluminum, i.e., aluminum with a Young's modulus of approximately 70 GPa, or 1010.sup.6 psi; a high strength plastic, i.e., a plastic having an ultimate tensile strength of at least 110 MPa; Kevlar, a para-aramid synthetic fiber; carbon fiber composites or a combination thereof. For example, the material of construction can include plastic molding over a steel insert.

(40) The inverted U-shaped stamped sheet metal receiver 40 has an inside cavity 45 that receives and houses the loading and ejection port 14 and moving parts including the lifter 15 that is an integral part of the stock 10 that fits inside the cavity 45 and forms the rear end of the firearm.

(41) At the base of the inverted U-shaped stamped sheet metal receiver 40 on the front end are left and right rectangular shaped tabs 50 and 53 stamped with holes 51 and 54 respectively for attaching the grip to the receiver via a frame pin. The rectangular shaped tabs 50 and 53 also include notches 52 and 55 respectively that are used to provide clearance for the selector catch axis which holds the selector catch, and when the trunnion is welded to the receiver, the selector catch axis can still be inserted or removed.

(42) At the rear end of the base of the inverted U-shaped stamped sheet metal receiver 40 are left and right triangular shaped tabs 60 and 62, respectively, stamped with holes 61 and 63. The left and right triangular shaped tabs 60 and 62 are used to provide support to holes 61 and 63 which fasten the rear end of the grip stock and receiver together via a second frame pin.

(43) In FIG. 8, the trunnion 70 that fits between the left and right rectangular tabs 50 and 53 is shown in greater detail. The trunnion is machined to have a left side 71 with three holes, 72, 73, 74 and a right side 75 with three holes 76, 77, 78 wherein the left side 71 and right side 75 are attached with a perpendicular cross piece 79 thereby forming a stabilizing structure that fits below the tubular magazine.

(44) When properly aligned between the rectangular tabs 50 and 53, the three holes in each of the left and right sides of the trunnion function as follows. Holes 72 and 76 align with notches 52 and 55, respectively to provide clearance for the selector catch axis which secures the selector catch. Holes 73 and 77 align with holes 51 and 54, respectively for a first frame pin to ride through attaching the front end of the grip stock and receiver together. Holes 74 and 78 are in a forward position beyond the tabs 50 and 53 for a dowel pin to be inserted which secures the cartridge stops.

(45) FIG. 9 is an enlarged perspective view of the barrel of the firearm of the present invention with muzzle plate 28 on the front end of barrel 26, sight base 29 and barrel extension 30 threaded at the rear end of barrel 26.

(46) FIG. 10 is an enlarged perspective view of the pistol grip of the present invention consisting of captor spring 12a that forms an assembly push pin that is inserted into a frame pin 12b, loading and ejection port 14, grip 16 and trigger 18.

(47) FIG. 11 is an enlarged perspective view of the stock 10 with lifter 15 having a right arm 15a and a left arm 15b. The stock 10 is inserted from the back of the inverted U-shaped sheet metal receiver 40 when the forearm herein is assembled. The stock 10 is sometimes called a hollow stock because it houses moving parts of the lifter 15 with two finger-like protrusions, a right arm 15a and a left arm 15b. The lifter 15 is a rigid U-shaped steel part that rotates on an axis to lift shells into a position to be fed into the chamber. On the downward rotation, the lifter also serves as the ejector, which aids in expelling the spent shell from the chamber.

(48) In FIG. 11, the stock is shown with reinforcing ribs of a honeycomb structure which serve to increase structural rigidity while using less material in the design; other known designs may be used that accomplish the purpose of increasing structural rigidity while reducing the amount of material required for manufacturing the stock.

(49) Disclosed herein is a firearm, such as, a shotgun, with a novel design wherein the parts of the firearm are secured and held in place by an inverted U-shaped stamped sheet metal receiver 40. The novel use of an inverted U-shaped sheet metal receiver 40 with a loading and ejection port 14 cavity is provided thereby advancing the art of firearm manufacture by disclosing a tubular magazine and receiver that is simple to manufacture, lightweight and compact with an increase in ammunition capacity when compared to comparable firearms, such as the Remington 870.

(50) While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.