Abstract:
A hand guard is provided for a firearm, such as a rifle, and may be suitable for maintaining the alignment of the hand guard, and any accessories coupled thereto, relative to the rifle. The hand guard may be configured so that at least a portion of the hand guard can be removed from the firearm and then re-installed on the firearm without significant change in the orientation and position of the hand guard. The hand guard may also be suitable for coupling accessories such as lights, scopes, laser sights, and other firearm accessories to the firearm.

Description:
FIELD OF THE INVENTION 
     The present application relates to components used with firearms and, more particularly, to hand guards and barrel clamps used on firearms, such as rifles. 
     BACKGROUND OF THE INVENTION 
     Firearms, such as rifles, oftentimes include a hand guard so a user can readily grasp the firearm effectively. For example, the user may need to grasp the firearm for carrying, transport, and firing of the weapon. Such a hand guard may be especially useful with longer firearms such as rifles. The hand guard should also be generally designed to accommodate for any recoil produced by the weapon during use. 
     Furthermore, hand guards may oftentimes be used for affixing accessories, such as lights, laser sights, scopes and other accessories to the firearm. In this regard, the hand guard may include a plurality of connection points, such as openings, for receiving accessories and/or accessory mounts for coupling one or more accessories to the firearm. 
     However, prior hand guards oftentimes suffer from a number of deficiencies. For example, hand guards, or at least a portion thereof, may need to be removed to permit cleaning, disassembly, and/or removal of parts of the firearm. Many prior hand guards involved complicated mechanisms for coupling and uncoupling portions of the hand guard to a firearm. Further, tools and small parts are also oftentimes used in prior hand guards to assemble the hand guard. In this regard, such hand guards may be more difficult to remove in the field as tools may not be readily available and/or small parts and fasteners may be easily lost. For example, some firearms include gas tubes that may need to be removed or serviced in the field, thereby requiring removal of at least a portion of the hand guard. However, prior hand guards may not be entirely suitable for field servicing, such as of gas tubes, because of the complicated mechanisms and small parts that may be easily lost in the field. 
     Additionally, as noted above, many hand guards also include connections for coupling accessories to the hand guard and ultimately, the firearm. However, when portions of the hand guard are removed, along with the accessories, it is possible for certain accessories, such as scopes and laser sights, to lose their alignment or otherwise “lose their zero.” This can be especially noticeable on longer weapons where minor changes in the orientation of the hand guard may significantly affect the alignment of any attached accessories. 
     SUMMARY OF THE INVENTION 
     In one form, a hand guard is provided for a firearm, such as a rifle, and may be suitable for maintaining the alignment of the hand guard, and any accessories coupled thereto, relative to the rifle. For example, the hand guard may be configured so that at least a portion of the hand guard can be removed from the firearm and then re-installed on the firearm without significant change in the orientation and position of the hand guard once installed. The hand guard may be especially suitable for longer guns, such as rifles, whereby the hand guard may be used to carry and/or hold the firearm during use. The hand guard may also be suitable for coupling accessories such as lights, scopes, laser sights, and other firearm accessories to the firearm. In another form, a plurality of accessories may be coupled to the hand guard at various positions on the hand guard. 
     According to one form, at least a portion of the hand guard may be readily removable without requiring tools or external fasteners. For example, an upper part of the hand guard may be removable relative to a lower part of the hand guard by manipulating a locking structure and sliding the upper part relative to the lower part. In one form, the lower part may be maintained on the firearm and serve as a reference for repositioning the upper part. The upper part may then be re-installed on the firearm via the lower part by manipulating the locking structure and then sliding the upper part relative to the lower part. The locking structure may cooperate with other structure on the hand guard to maintain the upper and lower parts on the firearm via a friction fit. As the lower part may be maintained on the firearm and the upper part is positionable on the lower part in a specific configuration, the upper and lower parts may be maintained substantially in alignment as established during the initial installation on the firearm. This may be significant as accessories may be coupled to the hand guard such that the alignment and/or “zero” of the accessories may be substantially maintained, even after removal and re-installation of a portion of the hand guard. 
     In accordance with one form, a hand guard includes an elongated housing including an upper part, a lower part and a locking structure. The upper and lower parts may be positioned to define an interior space when installed. The upper and lower parts may also be separable from one another without the need for tools or external fasteners. One of the upper and lower parts may include an interior portion with a first dimension that is sized to be received within the other of the upper and lower parts at an exterior portion having a second dimension larger than the first dimension. In one form, the upper part includes lower wall portions that are sized to fit within outer wall portions of the lower part. 
     In one form, at least one of the upper and lower parts including a protrusion extending toward the interior portion while the other of the upper and lower parts defines a slot configured to accept the protrusion. For example, the lower part may include a plurality of protrusions, such as posts, that extend inwardly toward an interior portion of the housing while the upper portion includes a plurality of slots configured to cooperate with the protrusions. 
     According to one form, the locking structure abuts the interior portion and cooperates with the protrusion and slot to limit movement of the upper and lower parts relative to one another when in an installed configuration. For example, the slot may be configured to permit the protrusion to slide through a portion of the slot and then abut an end portion of the slot, providing a force in a first direction while the locking structure abuts the interior portion and provides a force in an opposite direction. Therefore, in one form, the upper and lower parts may be maintained relative to one another via a friction-type fit. 
     In another form, a hand guard includes an elongated housing including an upper part, a lower part and a front securing structure. The upper and lower parts may be positioned to define an interior space when installed. The lower part has a lower exterior surface extending along a lower plane. The upper part has an upper exterior surface extending along an upper plane with the upper and lower planes being configured at an angle relative to one another so the upper and lower planes are not parallel. One of the upper and lower parts has an interior portion with a first dimension that is sized to be received within the other of the upper and lower parts at an exterior portion having a second dimension larger than the first dimension. 
     In one form, the locking structure is movable to an unlocked position thereby permitting the upper and lower parts to move relative to one another and disengage the protrusion from the slot. 
     In another form, a barrel clamp may also be provided. The barrel clamp may be used with a hand guard or other structure to secure the structure relative to the firearm. The barrel clamp includes a barrel engaging portion, a first housing engaging portion and a second housing engaging portion. The first housing engaging portion includes a first partially threaded portion and the second housing engaging portion includes a second partially threaded portion. The barrel engaging portion extends between the first housing engaging portion and the second housing engaging portion. The first and second housing engaging portions are movable between an open configuration and an installed configuration. For example, in the open configuration, the first and second housing engaging portions are separated from one another to permit a barrel of the firearm to be moved between the first and second housing engaging portions and positioned adjacent the barrel engaging portion. In the installed configuration, the first and second housing engaging portions are positioned adjacent one another such that the first and second partially threaded portions define a threaded opening extending in a first direction for receiving a fastener. The barrel engaging portion is at least substantially surrounding a circumference of a barrel of the firearm when in an installed configuration. 
     According to one form, the hand guard further includes a first channel positioned at a wall of the exterior portion configured to receive a wall of the interior portion and a second channel positioned at an opposing wall of the exterior portion configured to receive an opposing wall of the interior portion, the first and second channels defining the second dimension. 
     In one form, the locking structure includes a first spring positioned at the first channel and a second spring positioned at the second channel, and the first and second springs deflect towards the interior space to permit the interior portion to be secured within the exterior portion. 
     In accordance with one form, the exterior portion includes a plurality of protrusions and the interior portion includes a plurality of slots configured to receive the plurality of protrusions. 
     In one form, the slot is generally L-shaped to receive the protrusion and permit the upper and lower portions to move in a plurality of directions relative to one another. 
     According to one form, the locking structure includes at least one spring that deflects towards the interior space in the unlocked position. 
     In accordance with one form, at least one of the upper and lower parts includes a plurality of external openings configured to receive and secure at least one firearm accessory. 
     In one form, the first housing engaging portion includes an upper portion having a first plurality of aligned teeth and the second housing engaging portion includes an upper portion having a second plurality of aligned teeth, the first and second plurality of aligned teeth being in alignment with one another when the first and second housing engaging portions are positioned adjacent one another. 
     According to one form, the barrel clamp further includes a first opening extending through the first housing engaging portion and a second opening extending through the second housing engaging portion, the first and second openings aligning with one another when the first and second openings are positioned adjacent one another to permit a fastener to pass therethrough in a direction that is substantially parallel to the first direction of the threaded opening. 
     In one form, the lower part includes a forward surface that extends along a forward plane such that the front plane is not perpendicular to either of the upper and lower planes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of one form of a hand guard for a firearm; 
         FIG. 2  is an exploded view of one form of a hand guard for a firearm; 
         FIG. 3  is a perspective view of one form of a hand guard installed on a firearm; 
         FIG. 4  is an exploded view of another form of a hand guard prior to being installed on a firearm; 
         FIG. 5  is a perspective view of the hand guard of  FIG. 4  as it is being installed on a firearm; 
         FIG. 6  is a perspective view of a barrel clamp prior to being installed on a firearm; 
         FIG. 6A  is a perspective view of the barrel clamp of  FIG. 6  when configured in an installed position; 
         FIG. 7  is a perspective view of the barrel clamp of  FIG. 6  as it is being installed on a firearm; 
         FIG. 8  is a partial cross-sectional view of a hand guard as it is being installed with the barrel clamp of  FIG. 6 ; 
         FIG. 9A  is a partial cross-sectional view of the lower part of a hand guard coupled to a barrel clamp; 
         FIG. 9B  is a partial cross-sectional view of the upper part being positioned with the lower part of the hand guard of  FIG. 9A ; 
         FIG. 9C  is a partial cross-sectional view showing a spring deflecting inwardly to permit the upper part of the hand guard to be positioned within the lower part of the hand guard of  FIG. 9A ; and 
         FIG. 9D  is a partial cross-sectional view showing the upper part of the hand guard sliding forward to an installed configuration relative to the lower part of the hand guard of  FIG. 9A . 
     
    
    
     DETAILED DESCRIPTION 
     Various forms and components of firearm hand guards and rails are provided and described herein. Referring to  FIG. 1 , one form of a hand guard  20  is shown. In this form, the hand guard  20  generally includes an upper part  22  and a lower part  24  with the upper and lower parts  22 , 24  defining an interior space  26  such that the upper and lower parts  22 , 24  generally surround a barrel of a firearm, when installed. 
     The hand guard  20  may also include a front securing structure  28  for securing a front portion  30  of the hand guard  20  to a firearm. In one form, as shown in  FIG. 1 , the hand guard  20  includes a rail interface  32  positioned on the upper part  22 . The rail interface  32  may take a variety of forms, such as a dovetail shape, as shown in  FIG. 1 , whereby accessories, such as a scope, may be positioned and secured thereon. 
     In one form, the upper part  22  includes sidewalls  34 , 36  that extend downwardly from the rail interface  32  while the lower part  24  includes sidewalls  38 , 40  that extend upwardly from a lower exterior surface  42 . In one form, the sidewalls  34 , 36  are separated by a dimension such that they fit within at least a portion of the dimension between sidewalls  38 , 40 , such as shown in  FIG. 1 . 
     The upper and lower parts  22 , 24  may also include securing structure, such as openings  43 , 44  in lower part  24  and openings  46 , 48  in upper part  22 . When the upper part  22  is installed with the lower part  24 , the openings may be positioned such that fasteners, such as screws  50  may be positioned through the openings  43 , 44  and into openings  46 , 48 . In this regard, in one form, the openings  46 , 48  may be threaded to receive the fasteners. The lower part  24  may also include one or more flanges  52  for contacting the upper part  22  and/or guiding the upper part into position during installation. 
     It should be appreciated that while the upper part  22  is shown as being positioned within the lower part  24 , the hand guard  20  may also be configured such that the lower part  24  is positioned within the upper part  22 . Similarly, the upper and lower parts  22 , 24  may include any number of different openings and/or structures for securing the upper and lower parts  22 , 24  relative to one another. 
     Either and/or both of the upper and lower parts  22 , 24  may include structures for attaching accessories to the hand guard  20  and firearm. For example, as shown in  FIGS. 1 and 2 , the lower part  24  includes generally key-shaped openings  60  for receiving accessories and/or accessory mounts. Such key shaped openings  60  include an enlarged portion  62  and a slot portion  64 . In one form, the slot portion  64  is generally beveled to receive a beveled portion from an accessory. In this regard, the accessory may include an enlarged portion extending from a beveled portion such that the enlarged portion of the accessory is inserted through the enlarged portion  62  and then slid through the slot portion  64 . Thereafter, the accessory may be tightened as the beveled portions of the accessory and the slot portion  64  contact one another to secure the accessory. Such a key-shaped opening  60  and accessory mount may be found on products from Noveske and/or Vltor. Other forms of openings, mounts and fastening systems are also contemplated as would be acceptable for use with a hand guard for a firearm. 
     The hand guard  20  also includes a slot  70  positioned at a rear portion  72  of the hand guard  20 . In one form, the slot  70  is positioned in the lower part  24  and is configured to cooperate with a structure, such as a flange (not shown) on a receiver  74  of a firearm  76 , such as shown in  FIG. 3 . Such a flange is generally known by those skilled in the art and understood as used on the receiver  74  of a firearm  76 . In this form, the rear portion  72  is supported by the receiver  74  of the firearm. Other mounting structures may also be used. Similarly, the slot  70  and flange can be reversed on the hand guard  20  and firearm. 
     As noted previously, the hand guard  20  may also include a securing structure  28  which may be removable from or permanently secured to the hand guard  20 . As shown in  FIG. 2 , the securing structure  28  is removably secured to the lower part  24 , such as at mounting portion  78 . In this form, the securing structure  28  may be fastened to the lower part  24  at the mounting portion  78  via one or more fasteners  79 . The securing structure  28  and the mounting portion  78  may be configured such that the two mate with one another or otherwise cooperate to minimize movement of the securing structure  28  when installed. For example, the securing structure  28  may include legs  80  that extend over the mounting portion  78  to minimize side-to-side movement of the securing structure  28 . 
     The securing structure  28  also includes a generally arc-shaped portion  82  that is configured to cooperate with a barrel clamp or other mounting structure, such as shown at  83 , on a firearm to secure the hand guard  20  to the firearm, such as will be described in more detail below. The arc-shaped portion  82  includes an opening  84  that is configured to receive a fastener  85  therein extending from the barrel clamp or other structure  83  on the firearm. Further, the securing structure  28  includes an opening  86  that is configured to align with an opening  88  in the hand guard  20  to secure the securing structure  28  thereto. 
     The hand guard  20  may be installed on a firearm, such as firearm  90  by having the upper part  22  initially separated from the lower part  24 . For example, the upper and lower parts  22 , 24  may be separated as shown in  FIG. 2 . By having the upper and lower parts  22 , 24  separated, the hand guard  20  may be easily positioned about the firearm  90  as well as permit other structures, such as a firearm gas tube, to be positioned on the firearm. The lower part  24  may then be positioned around a barrel  92  of the firearm with the slot  70  being slid into alignment with the receiver  74 . Next, the mounting structure  83  may be slid into position adjacent the securing structure  28 , which was previously mounted to the hand guard  20 . The mounting structure  83  is then secured to the hand guard  20  to maintain the lower part  24  in a desired position. Next, the gas tube (not shown), or other structures may be installed on the firearm  90 . Finally, the upper part  22  may be positioned on the lower part  24  and then secured thereto via fasteners or screws  50 . Once installed, the hand guard  20  may be used to mount accessories, scopes and the like to the firearm. 
     When installed, the upper part  22  and lower part  24  may be positioned and configured to be securely mounted on a firearm to maintain the positioning of any scopes or other structures mounted to the hand guard  20 , otherwise understood as maintaining the “zero” of the structures. The zero may be maintained during use and transportation of the firearm. Further, the upper part  22  may be removed, such as for cleaning and/or maintenance of the firearm, such as of the gas tube, and then reinstalled to substantially maintain the zero of the scopes or accessories. In other words, the upper and lower parts  22 , 24  may be quickly and easily returned to their installed and calibrated positions relative to one another after reinstallation. 
     Further, it should be noted that the upper and lower parts  22 , 24  may be positioned relative to one another to help maintain the relative positions of one another or otherwise increase the ease of installation. For example, when installed, the upper part  22  may have an upper exterior surface  96  that extends along an upper plane, such as represented at line A, while the lower part includes a lower exterior surface  98  extending along a lower plane, represented at line B. In one form, the upper and lower planes A,B are configured to be at an angle relative to one another such that they are not parallel. For example, the upper and lower planes A,B are positioned at an angle α relative to one another. In one form, the angle α is 1 degree and provides a slight lean back of the upper and lower parts  22 , 24 . Other angles are also contemplated including, but not limited to 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15 degrees and the like. This may help guide or otherwise maintain the positions of the structures of the hand guard  20 . 
     Similarly, the front portion  30  of the hand guard  20  may be positioned at an angle relative to other portions of the hand guard  20 . In one form, the front portion  30  extends along a plane, represented by line C, such that the front portion  30  is not perpendicular to either of the planes A or B. In this regard, the front portion  30  may extend at an angle of 91 degrees relative to plane B to help maintain the zero or otherwise assist in installation of the hand guard, such as when coupling to mounting structure  83 . Other angles are also contemplated including, but not limited to 80, 81, 82, 83, 84, 85, 86, 87, 88, 92, 93, 94, 95, 96, 97, 98, 99, and 100 degrees and the like. 
     Another form of a hand guard  100  is shown in  FIG. 4  prior to being assembled on a firearm  102 . The hand guard  100  includes a number of similar features and structures as shown and described for the hand guard  20 . The hand guard  100  also includes a number of additional and/or different features and structures and may be suitable for use with other firearms. For example, the hand guard  20  may be suitable for use on an AK-47 while the hand guard  100  may be suitable on a Saiga rifle. However, it should be appreciated by one skilled in the art that the features on the hand guards  20  and  100  may be combined, intermixed, swapped and the like to provide a hand guard for a specific firearm. For example, some of the features and structures on hand guard  100  may be configured for use with a hand guard for an AK-47 while features of the hand guard  20  may be configured for use with a Saiga rifle. The hand guards  20 , 100  may also be configured for use with other firearms, rifles and the like. 
     As shown in  FIG. 4 , the hand guard  100  generally includes an upper part  122  and a lower part  124  with the upper and lower parts  122 , 124  defining an interior space  126  such that the upper and lower parts  122 , 124  generally surround a barrel of a firearm, when installed. 
     The hand guard  100  may also include a front securing structure, such as barrel clamp  128  for securing a front portion  130  of the hand guard  100  to a firearm. In one form, as shown in  FIG. 4 , the hand guard  100  includes a rail interface  132  positioned on the upper part  22 . The rail interface  132  may take a variety of forms, such as a dovetail shape, as shown in  FIG. 4 , whereby accessories, such as a scope, may be positioned and secured thereon. 
     In one form, the upper part  122  includes sidewalls  134 , 136  that extend downwardly from the rail interface  132  while the lower part  124  includes sidewalls  138 , 140  that extend upwardly from a lower exterior surface  142 . In one form, the sidewalls  134 , 136  are separated by a dimension such that they fit within at least a portion of the dimension between sidewalls  38 , 40 , such as shown in  FIGS. 4-5 . Further, the lower part  122  includes a first channel  143  and a second channel  145  to receive the sidewalls  134 , 136  and assist in the assembly and/or securing of the upper and lower parts  122 , 124  relative to one another. However, it should be understood that the upper and lower parts  122 , 124  may be configured such that either one may be configured to fit, at least partially, within the other. 
     The upper and lower parts  122 , 124  may include a variety of protrusions and slots for coupling the upper and lower parts  122 , 124  together. For example, in one form, the upper part  122  includes a plurality of slots  144  while the lower part  124  includes a plurality of protrusions  146  that are designed to cooperate with the slots  144  during installation and for securing the upper and lower parts  122 , 124 . In one form, the slots  144  may be generally L-shaped with a generally vertical portion  148  and a generally horizontal portion  150  to permit movement of the slots  144  therein, as will be explained in more detail below. 
     As seen in  FIG. 4 , the protrusions  146  generally extend inwardly towards the interior space  126  to cooperate with the slots  144 . However, it should be understood that the position and configuration of the slots  144  and protrusions  146  may be modified. For example, the slots  144  may be positioned on the lower part  124  while the protrusions  146  may be positioned on the upper part  122 . Further, the protrusions  146  may extend outwardly, such as in the case where the lower part  124  is dimensioned to fit within the upper part  122  (not shown). Other coupling structures are also contemplated as well as placement and configuration of the coupling structures so as to permit the upper and lower parts  122 , 124  to be removably coupled to one another. 
     It should be appreciated that while the upper part  122  is shown as being positioned within the lower part  124 , the hand guard  100  may also be configured such that the lower part  124  is positioned within the upper part  122 . Similarly, the upper and lower parts  122 , 124  may include any number of different openings and/or structures for securing the upper and lower parts  122 , 124  relative to one another. 
     Either and/or both of the upper and lower parts  122 , 124  may include structures for attaching accessories to the hand guard  100  and firearm. For example, as shown in  FIGS. 4 and 5 , the lower part  124  includes generally key-shaped openings  160  for receiving accessories and/or accessory mounts. Such key shaped openings  160  include an enlarged portion  162  and a slot portion  164 . In one form, the slot portion  164  is generally beveled to receive a beveled portion from an accessory  165 . In this regard, the accessory  165  may include an enlarged portion extending from a beveled portion such that the enlarged portion of the accessory is inserted through the enlarged portion  162  and then slid through the slot portion  164 . Thereafter, the accessory  165  may be tightened as the beveled portions of the accessory  165  and the slot portion  164  contact one another to secure the accessory. Such a key-shaped opening  160  and accessory mount may be found on products from Noveske and/or Vltor. Other forms of openings, mounts and fastening systems are also contemplated as would be acceptable for use with a hand guard for a firearm. 
     The hand guard  20  also includes a slot  170  positioned at a rear portion  172  of the hand guard  100 . In one form, the slot  170  is positioned in the lower part  124  and is configured to cooperate with a structure, such as a flange  173  on a receiver  174  of a firearm  102 , such as shown in  FIG. 4 . One skilled in the art would understand that such a flange  173  is generally known and understood as used on the receiver  174  of a firearm  102 . In this form, the rear portion  172  is supported by the receiver  174  of the firearm. Other mounting structures may also be used. 
     The hand guard  100  may also include one or more friction fit structures, such as springs  176 , 178  that can be used to help secure the upper and lower parts  122 , 124 . The springs  176 , 178  are generally flat springs that are configured to deflect inwardly and/or outwardly, as will be described in more detail below. In one form, the springs  176 , 178  are secured at one end, such as by rivets, welding, or other fastening techniques. In one form, the springs  176 , 178  are secured such that they only deflect inwardly and outwardly and do not rotate about the secured point. Further, the springs  176 , 178  may be manipulated via openings  180 , 182  in the lower part  124 . The springs  176 , 178  may be positioned adjacent the channels  145 , 143  to cooperate with the channels  145 , 143  to retain the upper and lower parts  122 , 124  relative to one another as will be understood from the description below of the assembly of the hand guard  100 . It should be appreciated that other springs and other friction fit structures may also be utilized. Additionally, the springs  176 , 178  may be positioned in other locations on the lower part  124  as well as on the upper part  122 . 
     The hand guard  100  may also include a toothed portion  184 . As shown in  FIG. 8 , the toothed portion  184  may be positioned on the lower part  124  and directed inwardly towards the interior  126 . The toothed portion  184  may also be located and positioned elsewhere on the hand guard  100 . The toothed portion  184  also includes an opening  186 . Generally, the toothed portion  184  is configured to cooperate with the barrel clamp  128 , such as will be described in more detail below. 
     The barrel clamp  128  may be configured to be coupled to a barrel of a firearm and also secure the hand guard  100 . The barrel clamp  128  may include a barrel engaging portion  200 , a first housing engaging portion  202  and a second housing engaging portion  204 . The first housing engaging portion  202  includes a first partially threaded portion  206  while the second housing engaging portion  204  includes a second partially threaded portion  208 . The barrel engaging portion  200  generally extends between the first and second housing engaging portions  202 , 204 . As shown in  FIG. 6 , prior to installation, the first and second housing engaging portions  202 , 204  are separated from one another in an open configuration. The first and second housing engaging portions  202 , 204  can be moved to an installed configuration, such as shown in  FIG. 6A , whereby the first and second housing engaging portions  202 , 204  are positioned adjacent one another. 
     The barrel clamp  128  also includes a plurality of openings  210 , 212 , such as located on the first and second housing engaging portions  202 , 204  and as best seen in  FIG. 6 . The openings  210 , 212  are configured to cooperate with fasteners, such as screws  214  to maintain the barrel clamp in the installed configuration. When in the installed configuration, the first and second housing engaging portions are positioned adjacent one another such that the first and second partially threaded portions  206 , 208  to define a threaded opening  220  extending in a first direction which is configured to receive a fastener. When installed, the barrel clamp engaging portion  200  substantially surrounds a circumference of a barrel of a firearm. Furthermore, the first and second housing engaging portions  202 , 204  may include a first and second plurality of aligned teeth  224 , 226 . 
     The installation and use of the barrel clamp  128  and the hand guard  100  will be explained in more detail. The barrel clamp  128  is generally configured to start in the open configuration, as shown in  FIG. 6  such that the first and second housing engaging portions  202 , 204  may be sufficiently separated to be slid over the diameter of a barrel  228  of a firearm. After the barrel clamp  128  is positioned around the barrel  228 , the first and second housing engaging portions  202 , 204  may be brought together, such as through the use of a vise. Next, fasteners  214  may be positioned through the openings  210 , 212  to maintain the position of the barrel clamp  128  on the barrel  228  at a desired position. In this configuration, the opening  220  is configured to receive a fastener to secure the hand guard  100  to the barrel clamp  128 . The barrel clamp  128  may be installed prior to or concurrent with the hand guard  100   
     The lower part  124  may be installed on the firearm  102  in a similar manner as that described for hand guard  20 . More specifically, the lower part  124  may first be positioned on the firearm  102  whereby the slot  170  is positioned to couple with the flange  172  on the receiver  174  to secure the rear portion  172  of the hand guard  100 . Next, the toothed portion  184  is brought into alignment and contact with the first and second aligned teeth  224 , 226  of the barrel clamp  128 . Further, the opening  186  is aligned with opening  220  whereby a fastener  230  may be used to secure the lower part  124  to the barrel clamp  128 , such as shown in  FIG. 8 . In this form, the lower part  124  is generally secured to the firearm  102  via the flange  173  and the barrel clamp  128 . Further, the aligned teeth  224 , 226  and toothed portion  184  help maintain the position of the lower part  124  as the barrel clamp is secured to the barrel  228 . 
     After the barrel clamp  128  and lower part  124  are secured to the firearm  102 , the upper part  122  may be positioned on the lower part. The upper part  122  is coupled to the lower part as shown in the progression of  FIGS. 9A-D . As shown in  FIG. 9A , the slots  144  are generally brought into engagement to couple with the protrusions  146 . However, the rearmost portion  232  of the upper part  122  will not be able to fully engage the lower part  124  as the springs  176 , 178  interfere. To permit the upper part  122  to fully engage and permit all slots  144  to engage all protrusions  146 , the springs  176 , 178  must deflect inwardly toward the interior space  126 , as shown by arrow  234  in  FIG. 9B  for spring  178 . Spring  176  will deflect in an opposite direction, but still outwardly relative to the interior space  126 . 
     After the springs  176 , 178  have been deflected inwardly, the rearmost portion  232  of the upper part  122  may drop down into engagement with the lower part  124 , as shown by arrow  236 . In this regard, the sidewalls  134 , 136  may be positioned within the channels  145 , 143 . Further, the springs  176 , 178  are positioned inwardly relative to the sidewalls  134 , 136 . 
     Finally, the upper part  122  may be moved forward, in a direction indicated by arrow  240 , whereby the springs  176 , 178  may then extend outwardly, such as shown by arrow  242  for spring  178 . Spring  176  will deflect in an opposite direction, but still outwardly relative to the interior space  126 . Once the springs  176 , 178  have deflected back to the original positions, such as shown in  FIG. 4 , the springs  176 , 178  will generally abut the rearmost portion  232  of the upper part  122 . This will cooperate with the slots  144 , protrusions  146  and channels  145 , 143  to substantially maintain the upper part  122  in the same position relative to the lower part  124 . 
     The hand guard  100  may generally be configured to permit the hand guard  100  to be at least partially removed and then reinstalled so that the relative position of the hand guard is maintained in the same position as initially installed. In this regard, any accessories mounted to the hand guard  100  can maintain their “zero.” For example, a scope (not shown) mounted to the upper part  122  can maintain its zero even if the upper part  122  is removed from the lower part  124 , such as would be done to replace or maintain a gas tube (not shown) on a firearm. Further, because of the structures used to couple the hand guard  100  to the firearm, as well as the upper and lower parts  122 , 124  to one another, the hand guard  100  may generally maintain the zero of attached accessories when the firearm is used and transported. For example, the teeth help maintain the position of the barrel clamp and hand guard while the protrusions, slots, channels and springs help maintain the position of the upper and lower parts, even in view of recoil as well as other forces associated with transporting the firearm. 
     The hand guard may be manufactured from a variety of materials, such as would be understood by those skilled in the art. For example, the barrel clamp and hand guard may be made from materials including, but not limited to metals, alloys, polymers, carbon fiber, plastics, and other suitable materials. In one form, the barrel clamp and hand guard may be manufactured from aluminum and/or steel. 
     While the invention has been particularly described with specific reference to particular structural and functional embodiments, it will be appreciated that various alterations, modifications and adaptions may be based on the present disclosure, and are intended to be within the spirit and scope of the present application as defined by the following claims. For instance, while the present application has been exemplified with respect to certain forms of firearms, it will be appreciated that the application is generally applicable to any type of firearm, such as a rifle, and may include any and/or all of the features and structures from any of the embodiments described herein.