Patent application title: RIFLE HANDGUARD SYSTEM WITH INTEGRATED BARREL NUT
David Stanowski (Galveston, TX, US)
Robert Bruce Davies (Galveston, TX, US)
IPC8 Class: AF41C2316FI
Class name: Firearms stocks
Publication date: 2015-05-21
Patent application number: 20150135572
A handguard system for use on a rifle having a barrel and a receiver, the
hand guard system includes a barrel nut having an inner surface with a
threaded portion adapted to threadably engage the receiver for securing
the barrel to the receiver and an outer surface, and a tubular handguard
having an end. The tubular handguard is receivable about the barrel and
is received about the barrel nut, engaging the outer surface thereof.
1. A handguard configured to be aligned with an upper receiver
comprising: a tubular portion, where the tubular portion has a long axis,
where the tubular portion has a plurality of openings along the long
axis, where the tubular portion has a non- circular cross-section, and a
first inner portion of the tubular portion, where the first inner portion
is configured to slide snuggly over a contact portion of an attachment to
a barrel, where the first inner portion is configured such that if the
tubular portion experiences a flexing force then the tubular portion
engages the contact portion to provide a counter force opposing the
flexing force, where the contact portion is part of the outer surface of
the attachment; an extension rail attached to the tubular portion; and an
alignment feature, where the alignment feature is configured to contact a
portion of an upper receiver and align the tubular portion with the upper
2. The handguard according to claim 1, further comprising: a channel in the tubular portion, where a portion of a gas push rod operating system fits within the channel.
3. The handguard according to claim 2, further comprising: a third rail, where the third rail is operatively attached to the tubular portion, where the third rail is substantially parallel to the second rail.
4. The handguard according to claim 1, where the alignment feature is at least one of a protrusion, a hole configured to accept an alignment pin, and a threaded hole configured to accept an alignment screw.
5. The handguard according to claim 1, where attachment is a barrel nut.
6. The handguard according to claim 5, where the inner portion is configured to fit snuggly over the barrel nut, where when the tubular portion is stressed the first inner portion contacts the barrel nut.
7. The handguard according to claim 6, where the long axis runs through the interior of the tubular portion, where any cross-section of the tubular portion perpendicular to the long axis is symmetric about an axis perpendicular to the long axis.
8. The handguard according to claim 7, where the plurality of openings are periodic along a direction parallel to the long axis.
9. The handguard according to claim 8, further comprising: a fastener, where the fastener is at least one of a screw, pin, and latch, where the fastener is used to secure the alignment feature to at least one of the top of the receiver, the side of the receiver, and the bottom of the receiver.
CROSS-REFERENCE TO RELATED APPLICATIONS
 This application is a continuation of Pending Reissue application Ser. No. 12/860,083, filed Aug. 20, 2010 which is a reissue-continuation of Reissue application Ser. No. 11/361,036, filed Feb. 23, 2006 for U.S. Pat. No. 6,694,660 issued Feb. 24, 2004 (U.S. patent application Ser. No. 10/105,700 filed Mar. 25, 2002). (i.e., This application is a Bauman type continuation application).
FIELD OF INVENTION
 This invention relates to rifle accessories. More particularly, the present invention relates to handguards for rifles.
 Long guns, and in particular rifles, have long been known. Rifles, due to their length, are typically fired using two hands. One hand is placed proximate the trigger assembly and the other is typically placed down the barrel from the trigger assembly. Rifles conventionally include a stock fabricated of wood. The stock typically includes a fore stock which extends some distance down the barrel. The fore stock is grasped by the shooter to provide balance and facilitate aiming the rifle. The shooter's hand is protected from the heat of the barrel during firing by the fore stock. Many modern rifles often employ synthetic materials for the stock, and still employ a fore stock. Other rifles do not include a single stock, but have a receiver to which a butt stock and a barrel are attached. The hand of a shooter is protected from the barrel by a handguard attached to the barrel. The M16 with its various permutations is an example of this type of rifle.
 In an M16, a handguard consists of an upper and a lower handguard fitted around the barrel and attached thereto at both ends. While effective for protecting the hand of a shooter, pressure on and from the handguard can cause minor flexing of the barrel. Flexing or distortion of the barrel can cause sighting problems and bullet deflections, each of which is detrimental to accuracy. Additionally, multiple parts are required for attachment of the handguard, increasing complexity, cost and difficulty of attachment.
 It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.
 Accordingly, it is an object of the present invention to provide a new and improved handguard system with attachment at only one end.
 Another object of the invention is to provide a handguard system which can be employed on existing rifles.
 And another object of the invention is to provide a handguard system that is easily installed and aligned.
 And yet another object of the invention is to provide a handguard system which will improve accuracy.
 Briefly, to achieve the desired objects of the instant invention in accordance with a preferred embodiment thereof, provided is a handguard system for use on a rifle having a barrel and a receiver. The hand guard system includes a barrel nut having an inner surface with a threaded portion adapted to threadably engage the receiver for securing the barrel to the receiver and an outer surface, and a tubular handguard having an end. The tubular handguard is receivable about the barrel and is received about the barrel nut, engaging the outer surface thereof.
 In a more specific aspect, provided is an extension rail coupled to the handguard. The extension rail includes a receiver portion extending beyond the handguard, a dovetail groove formed in an underside of the receiver portion of the extension rail having a cross-sectional shape substantially identical to a cross- sectional shape of the rail on the receiver, for receipt of the rail therein, and fastening members for fastening the extension rail to the rail. A portion of the tubular handguard underlying the extension rail is removed to form a channel therebetween.
BRIEF DESCRIPTION OF THE DRAWINGS
 The foregoing and further and more specific objects and advantages of the instant invention will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment thereof taken in conjunction with the drawings, in which:
 FIG. 1 is an exploded perspective view illustrating an upper receiver and barrel assembly of an M16A2 rifle;
 FIG. 2 is a exploded perspective view of the rifle of FIG. 1 with portions of the barrel and upper receiver illustrated, showing the conventional handguard replaced by a handguard system according to the present invention;
 FIG. 3 is an exploded perspective view of the handguard system and the integrated barrel nut according to the present invention;
 FIG. 4 is an end view of the integrated barrel nut of the handguard system of FIGS. 2 and 3;
 FIG. 5 is a side view of the integrated barrel nut of FIG. 4, with a portion 5- 5 cut away;
 FIG. 6 is a partially exploded side view illustrating a portion of a rifle with the handguard system according to the present invention;
 FIG. 7 is an exploded side plan view of the handguard and extension rail of the present invention;
 FIG. 8 is a top plan view of the handguard of the present invention; and
 FIG. 9 is an end view of the handguard and extension rail of the present invention.
 Turning now to the drawings in which like reference characters indicate corresponding elements throughout the several views, attention is first directed to FIG. 1 which is a partial exploded view of a rifle 10 of the type referred to as an M16A2, illustrating an upper receiver 11, a barrel 12 and a handguard system 14. Barrel 12 has a base end 18 and a muzzle end 19. Handguard system 14 is used to cover barrel 12 intermediate base end 18 and muzzle end 19 to provide a comfortable grip and to provide protection for a shooter's hand from the heat of barrel 12 during firing. Base end 18 of barrel 12 is attached to upper receiver 11 by a barrel nut 20.
 A spring loaded delta ring 22 fits over barrel nut 20 and is part of handguard system 14 for retaining an upper handguard 23 and a lower hand guard 24. Delta ring 22 is biased forwardly, toward muzzle end 19 of barrel 12 by a spring 26 and retaining ring 27. A front sight assembly 28 is fixed to barrel 12 proximate muzzle end 19 and includes a tube cap 30. The grip halves are fitted between delta ring 22 and tube cap 30. Insertion and removal is accomplished by forcing delta ring 22 rearwardly, against the bias, increasing the separation between delta ring 22 and tube cap 30. Ends of upper handguard 23 and lower hand guard 24 are inserted into delta ring 22, and the opposing ends are received by tube cap 30. Delta ring 22 is then permitted to return to the normal forward position, securing upper handguard 23 and lower hand guard 24. A gas tube 32 extends along barrel 12 between an operating mechanism carried by upper receiver 11 and tube cap 30. Gas tube 32 extracts gas from barrel 12 during firing and redirects it back to the operating mechanism.
 While somewhat effective, attachment of both ends of the grip to the barrel can distort the accuracy of the rifle. Pressure or torque by the shooter on the hand guard translates directly into pressure on the barrel. Additionally, heating of the handguard by heat from the barrel can cause expansion of the handguard. Distortion of the handguard can put pressure on the barrel. Any pressure can flex the barrel, even to the slightest degree, which will cause a sighting error and deflection of the bullet.
 Turning now to FIGS. 2 and 3, a portion of a rifle 40 is illustrated. Rifle 40 is illustrated as an M16A3, but it will be understood that other rifles similar to that described above can be modified with a handguard system according to the present invention, generally designated 50. A portion of an upper receiver 42 is illustrated with a barrel 43 having a base end 44 received by a barrel receiving receptacle 45 of upper receiver 42. A flange 47 extends around the outer circumference of barrel 43 proximate base end 44 of barrel 43 and abuts barrel receiving receptacle 45 when base end 44 is inserted into upper receiver 42. An alignment pin 48 extends from barrel 43 proximate flange 47 to facilitate proper alignment of barrel 43 when base end 44 is inserted into upper receiver 42. When barrel 43 is properly inserted and aligned, an integrated barrel nut 52 is threaded onto barrel receiving receptacle 45 of upper receiver 42 and engages flange 47, securely holding barrel 43 in position.
 With additional reference to FIGS. 4 and 5, integrated barrel nut 52 includes an inner surface having a threaded portion 53 and a reduced portion 54 separated by a shoulder 55. Reduced portion 54 has a diameter smaller than the diameter of threaded portion 53 and flange 47, but sufficient to allow passage of barrel 43 therethrough. Threaded portion 53 is adapted to threadably engage barrel receiving receptacle 45, with shoulder 55 engaging flange 47. When threaded securely, integrated barrel nut 52 fastens barrel 43 to upper receiver 42 with shoulder 55 holding flange 47 against barrel receiving receptacle 45.
 Still referring to FIGS. 2-5, integrated barrel nut 52 further includes an outer surface 57 having an outer diameter. Parallel passages 58 extend longitudinally through integrated barrel nut 52 intermediate the inner surface and outer surface 57, and are formed entirely about the circumference thereof. Passages 58 provide space through which an operating or push rod 59 passes. Since integrated barrel nut 52 must be threaded onto upper receiver 42, the plurality of passages 58 insures one will align properly.
 Referring specifically to FIGS. 2, 3 and 6, once integrated barrel nut 52 is secured in position, a tubular handguard 60 is received about barrel 43. Handguard 60 has an end 65 defining an inner diameter slightly larger than the outer diameter of integrated barrel nut 52. End 65 is received about outer surface 57 of integrated barrel nut 52 and secured thereto by a rail extension which will be described presently, by a plurality of fasteners such as headed screws extending through apertures formed in handguard 60, or both. Handguard 60 is attached such that it is spaced from barrel 43 and attached only at integrated barrel nut 52. In this manner, a handguard is provided which is attached only at end 65 and thus will not deflect or put pressure on the barrel.
 Turning now to FIGS. 2 and 6, handguard system 50 preferably includes a rail extension generally designated 70. Upper receiver 42 includes a rail portion 71 on an upper surface. Rail portion 71 is employed for the attachment of various accessories such as sights, scopes, etc. Often, however, the existing rail on upper receiver 42 is too short for many purposes. Thus, extension rail 70 can be employed to extend the rail down barrel 43 along handguard 60.
 Extension rail 70 is fastened to the top of cylindrical handguard 60 with a receiver portion 72 extending outwardly past end 65. Extension rail 70 can be fastened to handguard 60 in many diverse ways, but a preferred method will be described presently. As handguard 60 is received over barrel 43, receiver portion 72 of extension rail 70 is fitted over rail 71. Receiver portion 72 of extension rail 70 is formed with an underside defining a dovetail slot 80. Slot 80 is shaped to receive rail 71 therein. Receiver portion 72 of extension rail 70 is preferably of a length substantially identical to or shorter than the length of rail 71. In this manner, when handguard 60 is correctly positioned, receiver portion 72 of extension rail 70 substantially covers rail 71. If receiver portion 72 is shorter than rail 71, a portion of rail 71 is exposed for attachment of accessory devices. Receiver portion 72 of extension rail 70 is fastened to rail 71 with set screws 82 extending through apertures 83 and engaging the top of rail 71. Receiver portion 72 of extension rail 70 aligns with rail 71 such that apertures 83 overlie grooves or notches formed in rail 71. Set screws 82 extend through apertures 83 and into the notches of rail 71 preventing longitudinal movement thereof. While extending the rail, extension rail 70 additionally acts to reinforce and help stabilize handguard 60. Set screws 82 extend through the top of extension rail 70 and engage the top of rail 71. Thus, when tightened, set screws 82 force rail 70 from rail 71 securely engaging the dovetail equally on both sides.
 Turning now to FIG. 7, a method of attaching extension rail 70 to handguard 60 is illustrated. With momentary reference to FIG. 8, handguard 60 includes space 90 extending longitudinally along an upper surface thereof. Opposing sides of Space 90 are intermittently connected by bridges 92, each having an aperture 93. Extension rail 70 is coupled to handguard 60 with screws 94 extending concurrently through apertures 95 formed therein and apertures 93. Once securely positioned, rail 70 is welded to handguard 60. Screws 94 are removed and bridges 92 are cut from the edges of space 90 and also removed. Referring now to FIG. 9, by removing bridges 92, a channel 98 is formed along handguard 60 and extension rail 70 which provides the space necessary for the operation of the push rod system.
 Various changes and modifications to the embodiments herein chosen for purposes of illustration will readily occur to those skilled in the art. To the extent that such modifications and variations do not depart from the spirit of the invention, they are intended to be included within the scope thereof which is assessed only by a fair interpretation of the following claims.
 Having fully described the invention in such clear and concise terms as to enable those skilled in the art to understand and practice the same, the invention claimed is.
Patent applications in class STOCKS
Patent applications in all subclasses STOCKS