Patent Publication Number: US-9835411-B2

Title: Integrated rail and sight system for firearm

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority to U.S. Provisional Application Ser. No. 62/103,875, filed Jan. 15, 2015, which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to firearms and, more particularly, to an integrated rail and sight system for a firearm that is detachable from the firearm. 
     BACKGROUND 
     The use of rails, such as Picatinny rails, on firearms is known. Such rails are used to mount optics, lights, lasers and other accessories. The use of aiming sights that are mounted to the top of the rails are also known. 
     A known drawback with existing rails and sights is the lack of interchangeability on a firearm. Typically, the rails are formed part of the upper receiver or upper portion of the firearm and cannot be removed or interchanged. Additionally, depending on the desired sights to be used on the firearm, to change out the sights, the mounted sights need to be removed from the rail and replacements mounted to the rail. Such changing of sights can be complicated and/or time consuming. 
     The present invention seeks to overcome these limitations and other drawbacks of the prior art, and to provide new features not heretofore available. 
     BRIEF SUMMARY 
     The present invention relates generally to a firearm that includes a detachable integrated rail and sight system. The invention may be used with a rifle, carbine, pistol, handgun, shotgun, air gun, long gun and the like. The rail of the invention slidably mounts to the top of the firearm and is also retractable and detachable from the firearm. In other words, the rail may slide on and off the top of the firearm in a manner described by the invention. The rail of the invention also includes integrated front and rear flip-down sights. Both sights may be pinned to the rail and can fold down to the rail such that they are flush with or seat below the top portion of the rail. This permits accessories to be mounted to the rail without the sights interfering with the mounting of the accessories or without the sights interfering with the operation of the accessories. Mounted to the flip-down sights are detachable tri-apertures. The tri-apertures include three different sized apertures that rotate around a central axis. The entire aperture assembly is detachable from the sight. The rail may also accommodate an ambidextrous side-charging handle assembly for charging the bolt assembly. The ambidextrous charging handle assembly may slidably mount to the upper receiver and between the upper receiver and the underside of the integrated rail and sight assembly. The handles of the charging handle assembly may extend through elongated slots or apertures formed in the side walls of the integrated rail and sight assembly. 
     Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of an exemplary firearm incorporating embodiments of the invention; 
         FIG. 2  is a partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 3  is another partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 4  is another partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 5  is a close-up partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 6  is another close-up partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 7  is another close-up partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 8  is a close-up partial perspective view of an exemplary front sight of the invention; 
         FIG. 9  is a close-up perspective view of an exemplary rear sight of the invention; 
         FIG. 10  is a close-up partial side view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 11  is a close-up perspective view of an exemplary rear sight of the invention; 
         FIG. 12  is a close-up perspective view of an exemplary rear sight of the invention; 
         FIG. 13  is a close-up perspective view of an exemplary rear sight of the invention; 
         FIG. 14  is a close-up perspective view of an exemplary rear sight of the invention; 
         FIG. 15  is a close-up perspective view of an exemplary rear sight of the invention; 
         FIG. 16  is a close-up perspective view of an exemplary handguard of the invention; 
         FIG. 17  is a partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 18  is a partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 19  is a partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 20  is a perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 21  is a side view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 22  is a side view of one embodiment of an exemplary integrated rail and sight system removed from an exemplary firearm; 
         FIG. 23  is a close-up partial perspective view of one embodiment of an exemplary handguard of the invention; 
         FIG. 24  is a close-up partial perspective view of one embodiment of an exemplary receiver assembly of the invention; 
         FIG. 25  is a view of components of an integrated rail and sight system of the invention; 
         FIG. 26  is a partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 27  is a partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 28  is a partial perspective view of one embodiment of an integrated rail and sight system of the invention; 
         FIG. 29  is a perspective view of an exemplary side charging handle that may be used with the integrated rail and sight system of the invention; 
         FIG. 30  is another perspective view of an exemplary side charging handle that may be used with the integrated rail and sight system of the invention; 
         FIG. 31  is another perspective view of an exemplary side charging handle that may be used with the integrated rail and sight system of the invention; 
         FIG. 32  is an exploded view of the components of the exemplary side charging handle that may be used with the integrated rail and sight system of the invention. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     While this invention is susceptible of embodiment in many different forms, there are shown in the drawings, and will herein be described in detail, preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspects of the invention to the embodiments illustrated and described. 
       FIG. 1  illustrates an example of a firearm  10  that may be used in connection with aspects of the present invention. The firearm  10  may be in the form of a tactical style rifle, such as an AR-15, M-16, M-4, etc. The firearm  10  generally includes a receiver assembly  11  defining an upper receiver and a lower receiver, a buttstock  12  connected to the rear of the receiver assembly  11 , a barrel  13  connected to the front of the receiver assembly  11 , and a forearm or forestock  20  (which may also be referred to as a “handguard” in the art). The receiver assembly  11  may include a firing mechanism and other components known in the art, such as a bolt, a bolt carrier, firing pin, etc. The barrel  13  in this embodiment is a free-floating barrel that is connected to the receiver assembly  11  and is supported by the connection to the receiver assembly. A different type of barrel  13  may be used in other embodiments. The barrel  13  has a muzzle  15  at the tip. The muzzle may include a muzzle brake, sound compensator or flash hider. 
     The forearm or handguard  20  may be connected to the barrel  13  and/or the receiver assembly  11  and cover a portion of the length of the barrel  13  between the receiver assembly  11  and the muzzle  15 . In one embodiment, the forearm or handguard  20  connects to the firearm  10  proximate the receiver assembly, at the rear end of the barrel  13 , using a threaded connection with threading inside the forearm  20 . In another embodiment, the forearm may be attached to the receiver through the use of fasteners. In another embodiment, the forearm  20  may not completely cover the barrel  13 , and, for example, may cover or be positioned adjacent one or more sides of the barrel  13 . The firearm  10  may also include other known components, such as a grip  17 , a trigger  18 , a magazine well  19  for holding a magazine (not shown), and/or other firearm components. It is understood that the firearm  10  may not include one or more of such components in other embodiments. Aspects of the invention may be utilized in connection with a firearm  10  as illustrated in  FIG. 1  or another type of firearm, including other types of rifles, carbines, pistols, handguns, shotguns, machine pistols, air rifles, paintball guns, or other firearms. 
     In the embodiments, the firearm  10  may have a detachable integrated rail and sight assembly  14  of the invention. Referring to  FIGS. 2 and 3 , the integrated rail and sight assembly  14  incorporates an elongated rail  22 , and a flip-down front sight  24  and a flip-down rear sight  26  both of which are integrated with the rail  22 . The rail  22  is configured for mounting of accessories. The rail  22  illustrated in this embodiment is a Picatinny rail, but other types or configurations of rails may be used in other embodiments. Examples of accessories that may be mounted on the rail of the firearm  10  may include, without limitation: sights, including fixed sights, adjustable sights, laser sights and reflex sights; scopes, night vision, or other optical equipment; grips or handles; auxiliary weapons; bipods, tripods, or other support devices. It is understood that multiple accessories may be mounted on the rail. 
     Referring to  FIGS. 2 and 3 , in one aspect of the integrated rail and sight assembly, the front sight  24  and rear sight  26  are shown in a flipped up position on the rail  22 . In other embodiments, one or both of the sights may be moved to a flipped down position. As described in further detail below, the rear sight  26  may include an elevation knob for adjusting the height of the rear sight. The rear sight  26  may further include an ambidextrous windage knob for adjusting the rear sight in a lateral direction to account for wind conditions. The windage knobs adjust a windage box onto which mounts a tri-aperture, as described in more detail below. The tri-aperture includes three different sized apertures or openings through which the operator lines up or aims the rifle. A different sized aperture may be desired by the operator depending on the operator&#39;s preference, the caliber of the firearm and the type of ammunition used. The tri-aperture is detachably mounted to the windage box. This allows the tri-aperture to be removed and other apertures to be mounted to the rear sight. 
     Referring to  FIG. 4 , there is depicted the front sight  24  flipped up from the rail  22 . The front sight  24  includes an elevation knob  28  for adjusting the height of a sight post  30 . The sight post is used to align the firearm at a target. The sight post is positioned between two opposing arc-shaped sight portions  32  that are designed to assist the operator in quickly aligning and sighting the rifle on the desired target. As depicted, an operator may adjust the vertical height of the sight post  30  by turning the elevation knob which will raise or lower the height or location of the sight post on the front sight. In an aspect of the invention, the front sight  24  may include a plunger pin  34  that is used to releasably flip up or flip down the front sight. The plunger pin is spring loaded, as described below. In other embodiments, the front sight might not include an elevation knob or other means to adjust the front sight post. 
     Referring to  FIG. 5 , the front sight may be moved from a flipped up position (shown in  FIG. 5 ) toward a flipped down position (as shown in  FIG. 7 ). In one embodiment, the operator may press plunger  34 , which incorporates a plunger spring  79 , which releases the sight from its flipped up position, and then rotate the front sight toward the flipped down position where the front sight will be positioned against the rail  22  and will seat flush with or slightly below the top portion of the rail. Once in this position, the plunger  34  will seat within a half-moon shaped support portion  35  of the front sight thereby holding the front sight in the flipped down position. 
     Referring to  FIG. 6 , the elevation knob  28  is designed to be recessed within an opening  29  formed in the front sight. By recessing the elevation knob  28 , the front sight can flip down completely and seat flat against the rail surface  37 . In other embodiments, the elevation knob  28  is not completely recessed within the opening  29 . The knob  28  may define vertical ribs or a knurled surface on the outer surface of the knob to provide a gripping surface for the operator. 
     Referring to  FIG. 7 , the operator may press the plunger  34 , which is actuated by the internal spring  79 , and with the use of an index finger may move the front sight toward the flipped down position. Once the plunger  34  is pressed and the front sight is rotated approximately 22.5 degrees, the operator may release the spring operated plunger  34  which will then move outwardly due to the spring force acting on the plunger. The front sight  24  will still be able to rotate toward the flipped down position until the plunger seats within the half-moon shaped portion  35  of the front sight. At this position, the front sight will be held in the flipped down position by the plunger acting on the half-moon shaped portion  35  and the front sight will lay flat against the rail surface  37 . 
     Referring to  FIG. 8 , there is depicted a close-up view of the plunger  34  and the half-moon shaped portion  35 . As depicted, the half-moon shaped portion defines a radius that substantially matches the radius of the plunger pin  36 . This configuration permits the plunger  34  to suitably seat within the half-moon shaped portion  35 . 
     Referring to  FIG. 10 , the front sight  24  is depicted in a fully flipped down position within the rail  22 . As can be seen, the front sight  24  will seat flush with or slightly below the top portion of the rail  22 . This will allow accessories to be placed on the rail  22  without the front sight interfering with the installation or operation of the accessories. As depicted, the plunger  34  seats within the half-moon shaped portion  35  to thereby hold the front sight  24  in the flipped-down position. Also depicted in  FIG. 10  is a second half-moon shaped portion  39  located on the front sight  24 . The second half-moon shaped portion  39  is sized and shaped to receive the plunger pin  36  when the front sight  24  is moved to the flipped up position. The portion  39  serves as a seat for the plunger pin  36  to hold the pin and consequently the front sight in the flipped up position. 
     Referring to  FIG. 9 , there is depicted an exemplary embodiment of the rear sight  26 . In one embodiment, the rear sight may include an elevation knob  40  for adjusting the height of the rear sight. The elevation knob is positioned within an elevation body  41  and is accessible through an opening  43  formed in the elevation body. The rear sight  26  may also include ambidextrous windage knobs  42  for adjusting the rear sight in a lateral direction to account for wind conditions. The windage knobs  42  define two opposing wheels that operatively connect to and adjust a windage box  44 . This is accomplished through a threaded pin  45  that extends between and joins the wheels to the windage box. By turning either of the wheels in either a clockwise or counter-clockwise direction, the threaded pin extending through the windage box will move the windage box laterally or side to side. This results in the sight aperture mounted to the windage box to be moved laterally to account for wind conditions. The windage knobs  42  are ambidextrous because at least one knob  42  is accessible from either the right side or left side of the firearm, thereby permitting the operator to adjust the rear sight with either a left hand or a right hand. 
     The windage wheels, pin, and windage box are all mounted and held together through a windage base  47 . The windage base also includes opposing and vertically extending brackets  49  that each define a hole for supporting the pin  45 . Connecting the windage base  47  to the elevation body  41  are vertically extending elevation pins  51 . In one embodiment, two elevation pins operatively join the windage base  47  to the elevation body  41  and permit the vertical movement of the windage base relative to the elevation body. The pins  51  also keep the windage base from twisting relative to the elevation body. This permits the windage base to be held in place more securely thus improving the integrity of the rear sight and thus the accuracy of the firearm. 
     As shown in  FIG. 11 , mounted to the windage box is a tri-aperture  54 . The tri-aperture includes three different sized apertures  56   a ,  56   b ,  56   c , or openings through which the operator lines up or aims the rifle. The tri-apertures rotate around a central axis so as to permit the operator to change the aperture from one size to another. In an exemplary embodiment, the tri-aperture is detachably mounted to the windage box  44 . This allows the tri-aperture to be removed and other apertures to be mounted to the rear sight  26 . 
     Referring to  FIG. 12 , the windage knob  42  is shown being adjusted from a left side of the firearm. The opposing windage knob  42  could also be easily adjusted from the right side of the firearm. In an alternative embodiment, the rear sight  26  could provide for only a single windage knob  26 . In this embodiment, the windage knob could be located on either the right or left side of the rear sight. 
     Referring to  FIG. 13 , the tri-aperture  54  may be detachably mounted to the windage box  44 . This allows the tri-aperture to be removed and remounted or other apertures to be mounted to the rear sight  26 . The tri-aperture defines a central post  57  extending outwardly from the planar aperture surface  58 . The central post may be mounted to the windage box by inserting the central post into an opening in the windage box. Located within the opening and within the windage box may be a spring urged spherical ball bearing. Located on the central post may be three spherical radii  60 . The radii may be formed into the post and in a circumferentially spaced-apart relationship. Each radius corresponds to a position on the central post that results in an aperture being positioned in a top most position that is also aligned with the rear sight. The spherical radii are configured to match the radius of the spherical bearing located within the windage box. The spherical radii  60  allow the central post to have a positive lock when rotating through the three positions. In other words, when the spherical bearing seats within a radius  60 , the central post is locked in that position. Upon rotating the tri-aperture, the spherical bearing moves out of the radius and will re-seat in the next radius after the tri-aperture is rotated to the next radius. At this point, the central post will be locked again and the next aperture  56  will be positioned in a top most position that is also aligned with the rear sight. 
     Referring to  FIG. 14 , the tri-aperture  54  may be removed from the windage box by pulling the tri-aperture  54  and post  57  out from the windage box. In one embodiment, the post  57  is held within the windage box with the spherical ball bearing. The spherical ball bearing is spring loaded within the windage box. In other embodiments, the post  57  is held within the windage box using other techniques. 
     Referring to  FIG. 15 , the rear sight  26  may be flipped down and located flush with or below the rail in the same manner as described above with respect to the front sight. Just like the elevation knob in the front sight, the elevation knob in the rear sight is recessed and offset to permit the rear sight to lay flat with the rail  22 . Also, just like the front sight, the rear sight includes a plunger and plunger pin that engages with a half-moon shaped portion when in the flipped down position and also engages with a second half-moon shaped portion when in the flipped up position. 
     Referring to  FIG. 16 , the handguard  20  is depicted mounted around the barrel. the handguard  20  may be removed from the firearm by removing the handguard socket head cap screws used to mount the handguard to the firearm. In one embodiment, the handguard may be made of a metal based material. In other embodiments, the handguard may be made from carbon fiber or from fiberglass. The rail and sight assembly  14  may be mounted to any handguard made of any of these material types. 
     Referring to  FIGS. 17 and 18 , the rear sight  26  is shown being removed from the rail. As depicted, to remove the rear sight, a punch and hammer may be used to remove the pivot pin  63  that connects the rear sight  26  to the rail  22 . The rear sight may then be lifted off the rail, as shown in  FIG. 18 . By removing the pin  63 , the rail  22  of the rail and sight assembly may then be slidably removed from the firearm. 
     Referring to  FIGS. 18-24 , in an aspect of the invention, the rail  22  of the integrated rail and sight assembly  14  may be slidably removable from the upper receiver of the receiver assembly  11  and the handguard of the firearm. As shown in  FIG. 19 , once the pin  63  and rear sight  26  are removed, a plastic hammer may be used to tap the rear of the rail  22  to slide it forward. In one embodiment, the rail  22  is slidable toward the front end of the firearm. In other embodiments, the rail  22  may be slidable toward the back end of the firearm. When sliding the rail toward the front end of the firearm, the rail  22  will slide until it is no longer connected to the upper receiver. The rail  22  may slide back on to the upper receiver in the same manner as it was removed. 
     Referring to  FIG. 20 , the integrated rail and sight assembly  14  is shown partially removed from the receiver assembly  11  and partially removed from the handguard  20 . As depicted, the integrated rail and sight assembly  14  is configured to slide across both the receiver assembly  11 , which may also have a Picatinny or Weaver rail, and the handguard  20 . In other embodiments, for handguards that also include a Picatinny or Weaver rail, the integrated rail and sight assembly  14  is configured to slide across those handguards as well. 
     As shown in  FIG. 21 , the integrated rail and sight assembly  14  is shown removed from the receiver assembly  11 . As depicted, the rail  22  of the integrated rail and sight assembly  14  is configured to extend over and slide along the Picatinny rail on the receiver assembly  11 . The integrated rail and sight assembly  14  can further slide along the handguard  20  until it is removed from the firearm  10  toward the muzzle end of the firearm. In one embodiment, the rail and sight assembly  14  may be mounted to the top surface of the handguard and/or receiver assembly. In other embodiments, the rail and sight assembly  14  may be mounted to other surfaces of the handguard and/or receiver assembly, including a side surface, to permit the side mounting of the front and/or rear sights. 
     Significantly, the integrated rail and sight assembly  14  when it is slidably mounted to the handguard and receiver assembly serves the beneficial purpose of aligning the receiver assembly with the handguard. This results in a more precisely aligned firearm because the integrated rail and sight assembly  14  now prevents the handguard from twisting or torqueing relative to the receiver assembly. This also results in a more solid firearm. The firearm will also be more accurate because the integrated rail and sight assembly  14  is a one-piece structure now having a rail located over the receiver assembly and handguard and which will perfectly align the receiver assembly with the handguard. This is in contrast to the standard separate rail on the receiver assembly and a separate rail on the handguard, which might not be perfectly aligned. If the receiver rail and the rail on the handguard are not perfectly aligned there will be inherent accuracy problems between the front sight mounted to the handguard and the rear sight mounted to the receiver assembly. That is, one sight might extend in a slightly different orientation relative to the other sight, thereby creating alignment problems. The present invention eliminates any potential alignment problems between the front and rear sights because of the integral one-piece rail construction that slidably mounts and extends across both the receiver assembly and the handguard. 
     Referring to  FIG. 23 , in one embodiment, the mating connection between the integrated rail and sight assembly  14  and the handguard and receiver assembly may be a dovetail connection. In other embodiments, the mating connection might be a tongue and groove connection. In yet other embodiments, other mating connections are possible. As depicted in  FIG. 23 , an elongated dovetail cut  70  may be made to a guide  72  on the handguard  20 . The guide  72  and dovetail cut may extend a partial or complete length of the handguard. In other embodiments where the handguard includes a rail, the dovetail cut may be included in the rail. In any of the embodiments, the rail  22  of integrated rail and sight assembly  14  may have a matching dovetail cut on the underside of the rail  22  to permit the rail  22  to engage with and slide along the dovetail cut  70  of the guide  72  or rail, if used. The rail  22  may slide along the guide  72  until the rail is fully mounted onto the firearm at which time the pin  63  may be inserted into opening  87  (shown in  FIG. 27 ) in the receiver assembly  11  and used to secure the rail  22  to the receiver assembly  11  of the firearm. 
     Referring to  FIG. 24 , in one embodiment, the receiver assembly  11  may include a dovetail cut  80  that may be made to a rail  82  on the receiver assembly  11 . In other embodiments, the mating connection might be a tongue and groove connection. In yet other embodiments, other mating connections are possible. The rail  82  and dovetail cut  80  may extend a partial or complete length of the receiver assembly. The rail  22  of the integrated rail and sight assembly  14  may have a matching dovetail cut on the underside of the rail  22  to permit the rail  22  to engage with and slide along the dovetail cut  80  of the rail  82  of the receiver assembly. With this embodiment, when the integrated rail and sight assembly  14  is removed from the receiver assembly, the rail  88  can still be used as a rail to mount accessories to the firearm. The dovetail cut  80  does not impede or prevent the full use of the rail  82  after the rail  22  is removed from the receiver assembly. 
     Referring to  FIG. 25 , there are depicted components of the integrated rail and sight assembly  14  that have been described previously. In one embodiment, the integrated rail and sight assembly  14  includes a rail  22  used for mounting firearm accessories, including optics, lights, sights, lasers and the like. The integrated rail and sight assembly  14  may also include a front sight  24  that is pinned to a front end of the rail through the use of a pin  63 . The pin  63  also permits the front sight to pivot from a flipped up position to a flipped down position. The pin  63  also permits the front sight  24  to be removed from the rail  22 . The integrated rail and sight assembly  14  and specifically the front sight  24  also includes a plunger  34  that is operatively mounted to the front sight and a spring  79  that permits the plunger to move relative to the front sight. As stated above, the plunger and spring permit the front sight to be locked or held in position in either the flipped up position or in the flipped down position relative to the rail. As shown in the figure, the front sight further includes a sight post that may be adjusted vertically through the use of the elevation knob. The integrated rail and sight assembly  14  may also include a rear sight  26  that is also pinned to the rail  22  through the use of the pin  63 . The pin  63  also permits the rear sight to pivot from a flipped up position to a flipped down position. The pin  63  also permits the rear sight  26  to be removed from the rail  22 . The rear sight  26  also includes a plunger  34  that is operatively mounted to the rear sight and a spring  79  that permits the plunger to move relative to the rear sight. As stated above, the plunger and spring permit the rear sight to be locked or held in position in either the flipped up position or in the flipped down position relative to the rail. As shown in the figure, the rear sight may also include a tri-aperture, ambidextrous windage knobs, and an elevation knob, as described above. 
     Referring to  FIGS. 26-28 , there are depicted additional images of the rear sight  26 . As discussed, the rear sight may include an elevation knob  40  for adjusting the height of the rear sight. The elevation knob may be positioned within the elevation body  41  and is accessible through an opening. The rear sight  26  may also include ambidextrous windage knobs  42  for adjusting the rear sight in a lateral direction to account for wind conditions. The windage knobs operatively connect to and adjust the windage box  44 . Connected to the windage box is a tri-aperture  54  that defines a plurality of different sized apertures  56 . The tri-aperture is retained by a spring and ball bearing inside the windage box. The different size apertures permit the operator to rotate the rear sight aperture to a different sized aperture to account for different calibers of rounds fired through the firearm and for bullet drop. The windage knobs/wheels are mounted and held to a windage base  47  which also supports the windage box. The windage base also includes opposing and vertically extending brackets  49  that support the windage knobs. Connecting the windage base  47  to the elevation body  41  are vertically extending elevation pins  51 . In one embodiment, two elevation pins operatively join the windage base  47  to the elevation body  41  and permit the vertical movement of the windage base relative to the elevation body. The pins  51  also keep the windage base from twisting relative to the elevation body. This permits the windage base to be held in place more securely thus improving the accuracy of the rear sight. The rear sight may be pinned to the rail  22  through the pin opening  87 . 
     As shown in  FIGS. 26 and 27 , the rear sight is positioned in a flipped up position or a first position. As shown in  FIG. 28 , the rear sight is positioned in a flipped down position or a second position. In the flipped down position, the rear sight will lay flat with the rail  22  and will seat flush with or slightly below the top portion of the rail  22 . As explained, this allows the rear sight to not interfere with any accessories mounted to the rail, but yet allows the rear sight to be connected to the rail and used in a flipped up position if desired. 
     Referring to  FIGS. 29-32 , an alternative embodiment of the firearm includes an ambidextrous side-charging handle assembly  100  that is mountable to and operable with the integrated rail and sight assembly  14  for charging the bolt assembly. The ambidextrous charging handle assembly  100  slidably mounts to the upper receiver and between the upper receiver and the underside of the integrated rail and sight assembly  14 . The charging handle assembly  100  may include a pair of opposing ears  102  that function as a charging lever. The ears extend outwardly from both sides of the firearm and can be operated by either hand to charge the firearm, thereby creating an ambidextrous charging handle assembly. The charging handle assembly  100  will mount to an elongated channel  104  formed in the top side of the upper receiver  103  and will slide along the upper receiver. The channel  104  may define a dovetail cut or similar cut that captures and holds down the charging handle assembly  100 . Unlike traditional charging handles that are located at the rear of the firearm, the charging handle is located forward on the firearm. A barrel nut  107  may be threadably mounted to the end of the upper receiver  103  for mounting a barrel, not shown, to the upper receiver  103 . 
     With respect to the charging handle assembly, the opposing ears  102  may be pinned to opposite sides of a charging lever block  106 . Each lever block  106  may be attached to opposing sides of a charging handle block  108 . The charging handle block  108  may be pinned through the use of pin  110  to a hole  111  in a charging handle operating rod  112 . The charging handle rod  112  defines an elongated body having an end  116  that defines a contact surface  118  configured to operatively contact and engage the bolt carrier. The end  116  defines a hole  120  that extends through the end. The gas operating tube may extend through the hole  120 . 
     The opposing ears  102  may define a gripping surface  122  and may be folded against the side of the firearm when not in use. The opposing ears permit ambidextrous use of the charging handle. The charging handle  100  is non-reciprocating. The charging handle is not affixed to the bolt carrier and only operatively connected to the bolt carrier so the charging handle does not run back and forth when the firearm cycles. In other words, in the exemplary embodiment, the charging handle does not serve as a forward assist to the bolt carrier. The opposing ears  102  may extend through opposing, elongated slots  130  formed in the sides of the integrated rail and sight assembly  14 . The elongated slots are located immediately beneath the top rail  22  of the rail and sight assembly. The elongated slots are sufficiently long so as to permit the ears to freely travel back and forth along the slots at least the same distance of travel as the bolt carrier does when the operator charges the firearm. 
     With the integrated rail and sight assembly  14  that is removable from the firearm, an operator can easily and quickly remove the front and rear sights and replace them with different types of sights. In an alternative aspect, the operator could remove the integrated rail and sight assembly  14  and replace it with another integrated rail and sight assembly having different sights already mounted to the rail. With the invention, the flexibility of the interchangeability of the sights creates numerous possibilities with the firearm. For example, an operator using the firearm for long range shooting with long range optics can quickly and easily change out the integrated rail and sight assembly with another integrated rail and sight assembly having sights for close quarter combat. The same is true for operators who use the firearm for competition shooting and who need to quickly change the sights for the next targets. 
     It should be understood that the integrated rail and sight assembly  14  described herein can be scaled down and mounted to other firearms, such as handguns, including the model 1911 handgun and other handguns. All the teachings and descriptions herein have complete application with a handgun. In one embodiment, the handgun may be manufactured with a dovetail cut in the top frame or slide of the handgun. The dovetail cut may be configured to receive the mating dovetail cut on the integrated rail and sight assembly to thereby permit the slidable mounting of the integrated rail and sight assembly to the top of the handgun. With the integrated rail and sight assembly, the operator who needs to quickly change out the sights needed for a particular competition target shooting will be able to do so. For example, if an operator needs to switch between a three-dot sight, a dot and bar sight, an express-style sight, a bright sight or a big dot sight, the operator only needs to slide off the integrated rail and sight assembly and slide onto the handgun the assembly containing the desired sights. Significantly, with an integrated rail and sight assembly of the invention, now only one handgun, rifle, long gun, or shot gun, etc., is needed for multiple types of shooting competitions because the operator only needs to change out the integrated rail and sight assembly to make the firearm usable for other types of shooting conditions or competitions. 
     Each of the various embodiments described herein may contain any components, structures, or other features of any of the other embodiments described herein, including any variations, additional features, or alternative embodiments described herein, whether or not illustrated in the drawing figures. 
     Several alternative embodiments and examples have been described and illustrated herein. A person of ordinary skill in the art would appreciate the features of the individual embodiments, and the possible combinations and variations of the components. A person of ordinary skill in the art would further appreciate that any of the embodiments could be provided in any combination with the other embodiments disclosed herein. It is understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein. The terms “first,” “second,” “top,” “bottom,” etc., as used herein, are intended for illustrative purposes only and do not limit the embodiments in any way. Additionally, the term “plurality,” as used herein, indicates any number greater than one, either disjunctively or conjunctively, as necessary, up to an infinite number. Further, “providing” an article or apparatus, as used herein, refers broadly to making the article available or accessible for future actions to be performed on the article, and does not connote that the party providing the article has manufactured, produced, or supplied the article or that the party providing the article has ownership or control of the article. Accordingly, while specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention.