Abstract:
Disclosed is a hand guard attachment system. The system in one form comprising a barrel nut affixed to an upper receiver of the firearm and a jam nut each with a threaded outer surface aligned with and co-axial to a bore of the firearm. The rapid configuration system may include a plurality of indexing pins aligned with, but not coaxial to the bore of the firearm. The hand guard may include an inner threaded surface where the threads cooperate with the threads of the jam nut and barrel nut. A method for attachment of the hand guard to the firearm is also disclosed. The method in one form including the steps of: threading the hand guard onto the jam nut and barrel nut; and tensioning the set screws. The method may include a step where the set screws are adjusted to manipulate the angle of the hand guard relative to the bore.

Description:
RELATED APPLICATIONS 
     This application claims priority benefit of U.S. Ser. No. 61/680,940, filed Aug. 8, 2012, incorporated herein by reference. 
    
    
     BACKGROUND OF THE DISCLOSURE 
     Field of the Disclosure 
     This application relates to the field of hand guard attachment systems for live fire firearms. 
     SUMMARY OF THE DISCLOSURE 
     Disclosed herein is a firearm hand guard rapid configuration system with examples of the interoperating components. The system in one form comprising: a barrel nut affixed to an upper receiver of the firearm. The barrel nut in one form comprising: a threaded outer cylindrical surface aligned with and co-axial to a bore of the firearm; a surface defining an inner cylindrical face aligned with and co-axial to a bore of the firearm; a plurality of surfaces defining indexing voids aligned with, but not coaxial to, the bore of the firearm; and wherein the indexing voids are formed (machined, cast or drilled) radially between the threaded outer surface and the inner cylindrical face of the barrel nut. 
     Also disclosed is a jam nut, comprising in one form a threaded outer cylindrical surface aligned with and co-axial to a bore of the firearm. This surface having a thread diameter and thread pitch as the outer cylindrical surface of the barrel nut. The jam nut also has a surface defining an inner cylindrical face aligned with and co-axial to a bore of the firearm. Generally, the jam nut is arranged wherein the indexing pins have an outer diameter slightly smaller than the indexing voids of the barrel nut so as to index therein such that the jam nut is longitudinally positionable relative to the barrel nut. The jam nut may also utilize a plurality of threaded set screw receivers aligned with but not coaxial to the bore of the firearm. 
     The rapid configuration system as recited above may be arranged wherein the plurality of set screws includes three or more set screws. 
     The rapid configuration system as recited above may further comprise a plurality of indexing pins aligned with, but not coaxial to the bore of the firearm. 
     The rapid configuration system may be arranged wherein the jam nut further comprises a surface defining a gas vent aligned with but not coaxial to the bore of the firearm. 
     The rapid configuration system, as recited above, may further comprise a vented hand guard having at one longitudinal end an inner cylindrical surface aligned with and co-axial to a bore of the firearm. This inner cylindrical surface having a thread diameter and thread pitch equivalent to the outer cylindrical surface of the barrel nut and jam nut. 
     A method for attachment of a hand guard to a firearm is also disclosed. The method comprising the steps of: providing a rapid configuration system as recited herein; threading the hand guard onto the jam nut and barrel nut; and tensioning the set screws thus imparting tensional forces between the threads of the hand guard engaging the barrel nut, and the threads of the jam nut wherein such tensional forces prohibit rotation and removal of the hand guard relative to the jam nut. 
     The method for attachment of a hand guard to a firearm as recited above may include a step wherein the set screws are adjusted independently so as to manipulate the angle of a center longitudinal axis of the hand guard relative to the bore of the firearm. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective partially exploded view of several components of the disclosed apparatus. 
         FIG. 2  is a perspective view of one component of the disclosed apparatus. 
         FIG. 3  is an end perspective view of the disclosed apparatus. 
         FIG. 4  is a side view of the components shown in  FIG. 1 . 
         FIG. 5  is a perspective partially assembled view of the components shown in  FIG. 1  with additional components added thereto 
         FIG. 6  is a perspective assembled view of the components shown in  FIG. 1  with additional components added thereto. 
         FIG. 7  is a side sectional view of the components shown in  FIG. 6 . 
         FIG. 7   a  is a side sectional view taken along the axis of the bore of the firearm. 
         FIG. 7   b  is a detail exploded view of  FIG. 7   a.    
         FIG. 8  is an end perspective view of the components shown in  FIG. 6 . 
         FIG. 9  is a perspective view of a hand guard component in one form. 
         FIG. 10  is a perspective view of the disclosed apparatus in a fully assembled arrangement attached to a firearm. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Disclosed herein is a firearm hand guard rapid configuration system for the attachment and alignment of a hand guard to the receiver portion of the firearm. For examples, the firearm could be a rifle such as an AR-15, M-16, or similar tactical style rifle wherein a shooter (user) would normally grasp the trigger handle with their shooting hand and may well grasp the hand guard or forward portion of the receiver with their opposing hand in a tactical situation. 
     Commonly, such hand guards are attached in such a manner that the angle of the hand guard is not adjustable relative to the bore of the firearm. The bore of the firearm is the cylindrical passageway down the center of the barrel through which the bullet (projectile) will pass in its trajectory from the chamber of the firearm through the receiver, through the hand guard attachment system, and through a barrel and optional flame arrestor, silencer, or other muzzle end component(s). In addition, some prior art hand guards were simply threaded onto a barrel nut. In some applications, such hand guards were found to work themselves loose as the firearm is manipulated and fired. To counter this, such hand guards may be further fixed in place by way of screws, fasteners threaded radially through the hand guard, or alternatively fixed by way of an external jam nut. In such applications, the screws or other fasteners usually detract from the visual appeal and many be tacitly unappealing as well. As a shooter will often grasp the firearm by the hand guard, such tactile interference is detrimental. In addition, when such fasteners are threaded into the barrel nut, there is little rotational adjustability. 
     Before beginning a detailed description, and axes system  10  is shown in  FIG. 1  generally comprising a longitudinal axis  12  aligned with the center bore of the firearm, and a radial axis  14  which is transfers to the longitudinal axis  12 . This axes system and the orientation of the figures (drawings) in this application are intended to aid in understanding of the disclosed apparatus and are not intended to limit the application to any particular orientation. For example, firearms may be fired in an inverted orientation from that shown in the figures, or generally in any orientation. 
     Looking to  FIG. 1  an attachment system  20  is shown mounted to the receiver  22  of a firearm  24 . While only a small portion of the firearm  24  is shown, (the receiver portion) such firearms are well known in the art and generally comprise no novel features relative to this disclosure. In one example, the forward end  26  of the firearm comprises a barrel nut  28  which may be mounted to the receiver  22  by welding, adhesives, fasteners, or may alternatively be formed as a (unitary) portion of the receiver  22  cast or machined therewith. In the example shown in  FIG. 7 , it can be seen that a portion of the male threads  48  extending from the front of the receiver  22  are cut away. A small portion of female threads  48  on the inner surface of the barrel nut  28  are also shown. The barrel nut  28  comprises a cylindrical outer surface  30  having threads  32  cut or otherwise formed there in. The male threads  32  are specifically configured to engage female threads  34  ( FIG. 7 ) on an inner cylindrical surface  36  of the hand guard  38 . 
     Looking back to  FIG. 1 , it can be seen how in this example, the barrel nut  28  comprises a number of surfaces  40  defining indexing voids  42 . In addition, the barrel nut  28  in this example comprises an inner cylindrical surface  44  which is aligned (concentric) with the bore of the firearm. 
     A barrel extension  88  may extend through this cylindrical surface  44  to engage the forward end  26  of the receiver  22 . Several different embodiments of such a barrel extension  88  are disclosed in the prior art. 
       FIG. 1  also shows a jam nut  50  having an outer surface  52  with male threads  54  thereupon. The threads  54  generally have the same diameter and pitch as the male threads  32  of the barrel nut  28 . In this way, the female threads  34  ( FIG. 7 ) of the hand guard  38  may be threaded onto the jam nut  50  and the barrel nut  28  in succession. This example of the jam nut  50  also comprises cylindrical threaded voids  56  through which set screws  58  may be utilized. The set screws  58  are threaded into the jam nut  50  and when correctly rotated the rearward surface of the set screws engage the forward surface  60  of the barrel nut  28  or. The operation thereof will be disclosed in more detail. In one form, one or more of the set screws may be replaced with fixed pins, where other pins are moveable (threaded). The overall design of this portion is to drive the jam nut away from the washer and/or barrel net to allow for alignment of the center axis of the hand guard to the barrel nut and firearm. In other examples, cams or balls may be utilized to the same end. 
     In another example, the threaded assembly utilizes a bayonet-style or Dzus-style attachment or equivalent. For example, quarter-turn fasteners are used to secure panels in equipment, airplanes, motorcycles, and racing cars that must be removed often and/or quickly. These fasteners are of an over-center design, requiring positive sustained torque in one direction to unfasten. Thus, any minor disturbance to the fastener will correct itself rather than proceed to further loosening as it would in threaded fasteners. Such fasteners are well fitted to application in firearms where firing of the device causes repeated disturbance. 
     In one form, the jam nut  50  further comprises a plurality of indexing pins  62  which are fixed within pin receiving surfaces  64 . The indexing pins  62  may be threaded into, press fit, welded, adhered, fastened, or otherwise engaged fixedly within the pin receiving surfaces  64 . When utilized, the indexing pins  62  engaged the indexing voids  42  of the barrel nut to prohibit rotation of the jam nut  50  relative to the barrel nut  28 . The jam nut  50  may also comprise a surface (opening) defining a vent  66  which generally passes through the jam nut  50  for the venting of chamber exhaust gases there through. The vent  66  should align with the gas hole vent tube of the receiver  22 . Such alignment is described in U.S. patent application Ser. No. 10/648,888 incorporated herein by reference. In one example, the jam nut  50  comprises an inner cylindrical surface  68  which may have the same inner diameter as the surface  44  previously described. 
     Also shown in  FIG. 1  is a compression washer  70  having an outer surface  72  which is generally of a smaller diameter than the outer surface  30  of the barrel nut  28  and also smaller than the diameter of the outer surface  52  of the jam nut  50 . This way, when the hand guard  38  is threaded onto the jam nut  50  and the barrel nut  28 , the washer  70  is at least initially allowed some degree of longitudinal movement within the female threads of the hand guard  38 . The washer  70  one form also comprises a plurality of surfaces defining pin receivers  72  which allow the indexing pins  62  previously described to pass there through. The washer  70  also comprises a cut away portion forming surface  74  which is generally aligned with the vent  66  of the jam nut  50  again to allow exhaust gases to pass there through. In the example shown in  FIG. 1 , the washer  70  comprises a forward face  76  which engages the rear surface  78  of the jam nut  50  when the set screws  58  are released. When the set screws  58  are rotated so as to travel longitudinally toward the washer  70 , they will contact and press against the forward face  76  of the washer  70 . The rear surface  80  of the washer  70  will then be pressed against the forward surface  82  of the barrel nut  28  and when further tensioned will result in pressure being exerted between the radially outward threads of the barrel nut  28  and the jam nut  50 . Thus, when the hand guard  38  is threaded onto nuts  28 / 50 , and the set screws  58  are tensioned, the hand guard  38  will be substantially prohibited from rotating. This will also assist in aligning of the hand guard with the axis (bore) of the firearm. 
     This arrangement also allows the hand guard to be threaded onto the nuts  28 / 50  and held in place in any relative rotational position desired. The set screws  58  can be very easily seen in the sectional end view of  FIG. 8  with the hand guard  38  partially cut away, it can be seen by looking to  FIG. 6 , that the set screws  58  are not readily visible in most external views of the apparatus. In addition, this view does not take into consideration shadows cast by the hand guard  38  and that these shadows me even more significantly hide the set screws  58  and/or pins  62  from external view. 
     While the alignment pins  62  and washer  70  are very beneficial in some applications, the device in other applications does not rely on these components. 
     While the embodiment shown utilizes a large number of indexing voids  42 , the device may be formed with fewer indexing voids, as long as the number of indexing voids is at least the same as the number of indexing pins when indexing pins are used. 
     In addition, looking to  FIG. 8 , alignment of the longitudinal axis of the hand guard  38  relative to the bore of the firearm may be selectively adjusted by selectively tensioning and releasing the set screws  58 . While the set screws are generally numbered  58 , an alpha-numeric system is utilized wherein each individual set screw has an alphabetic suffix to indicate a particular set screw within the general group of set screws  58 . For example, looking to  FIG. 8 , the top right set screw is indicated as  58   a , and going clockwise around the bore, they are numbered  58   b ,  58   c , and  58   d  in sequence. Thus, when the set screw  58   a  is tensioned, the longitudinally outward end  84  of the hand guard  38  moves in direction of travel  86   a . The directions of travel  86   b - 86   d  correspond to tensioning of set screws  58   b - 58   d  respectively. Alignment may be slightly different if 2, 3, 5, 7 or any other number of set screws are utilized. 
     While the set screws  58  shown herein utilize an Allen or Hex wrench to tension, flathead, Phillips, Torx, or other configurations may work equally as well. 
     While the present invention is illustrated by description of several embodiments and while the illustrative embodiments are described in detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications within the scope of the appended claims will readily appear to those sufficed in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicants&#39; general concept.