Patent Publication Number: US-2013227871-A1

Title: Cancellation muzzle brake assembly

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present patent application is a formalization of previously filed, co-pending U.S. Provisional Patent Application Ser. No. 61/583,942, filed Jan. 6, 2012 by the named inventor of the present Application. This patent application claims the benefit of the filing date of this cited Provisional patent application according to the statutes and rules governing provisional patent applications, particularly 35 U.S.C. §119(a)(i) and 37 C.F.R. §1.78(a)(4) and (a)(5). The specification and drawings of the Provisional patent application referenced above are specifically incorporated herein by reference as if set forth in their entirety. 
    
    
     BACKGROUND OF THE PRESENT DISCLOSURE 
     1. Field of the Present Disclosure 
     The present disclosure is directed generally to a muzzle brake assembly for mounting on a muzzle of a firearm to provide a reduction in the felt recoil and muzzle jump of the firearm upon firing, while additionally providing a reduction in sound levels produced by discharge of a round of ammunition as compared to other muzzle brake devices. 
     2. Related Art 
     Muzzle brakes for firearms such as rimfire or centerfire rifles typically include ports or baffles in an attempt to reduce recoil and muzzle movement such as muzzle rise upon discharge of the firearm. Often these muzzle brakes significantly increase the resultant sound volume upon discharge of a firearm as compared with the use of no muzzle brake on the firearm. This can lead to hearing problems for shooters exposed to such increased sound volumes. Moreover, many muzzle brakes available are complicated and costly to manufacture, and can provide limited recoil reduction. 
     SUMMARY OF THE PRESENT DISCLOSURE 
     The present disclosure addresses the foregoing needs and provides for a muzzle brake assembly that enables several benefits, including an ability to reduce firearm recoil by redirecting the propellant gases in a new manner, substantial reduction or elimination of muzzle movement and/or an increased muzzle braking assembly effect provided upon discharge of a round of ammunition from the firearm, lessening or maintaining the acoustic signature of the firearm as compared to conventional brake designs, and which has a relatively easy and low cost of manufacture by current machining practices, thereby minimizing cost of manufacturing. 
     Accordingly, in one aspect of the present disclosure, the muzzle brake assembly for a firearm includes a body adapted to be coupled to the muzzle end of a barrel of a firearm and having an outer surface. The body generally will be configured with a bore having a central axis and aligned with the muzzle of the firearm barrel to permit passage of a round of ammunition along the axis. A plurality of ports in fluid communication with the bore are formed along the body. In one embodiment, the plurality of ports are arranged in pairs around a circumference of the body with one port of each pair positioned opposing the other port of the pair to cause intermixing of exiting compressed gas from the paired ports thereby providing at least one of: a reduction in muzzle movement, reduction in sound and reduction in recoil effect. 
     According to another aspect of the present disclosure, the muzzle brake assembly for a firearm includes a body having a bore and a plurality of adjacent ports arranged in annular rings or recesses around the circumference of the body and each extending through the bore into fluid communication with the bore. Each of the ports further will include an inlet and an outlet for venting or exhausting pressurized gases generated from firing a round of ammunition from the firearm. The outlets of at least a subset of the adjacent ports are arranged in an opposing relationship and are oriented at angles with respect to a control axis of the bore of the body to direct intermixing of compressed gases from the bore, and/or to direct at least a portion of the gases away from the outer surface of the body. This intermixing of pressurized gases helps cause redirection of a pressure wave created by the exiting gases, providing at least one of: a reduction in muzzle movement, reduction in sound and reduction in recoil effect. The body further can be formed with the barrel of the firearm or can include an attaching mechanism for detachably coupling the muzzle brake assembly to the barrel. 
     In yet another aspect of the present disclosure, a method for forming a muzzle brake assembly for a firearm is provided, including the steps of forming a body having a bore along an axis, the body further having an outer surface, and forming a plurality of adjacent ports arranged around a circumference of the body and in fluid communication with the bore for venting or exhausting portions of the pressurized gases from firing of a round of ammunition from the bore. At least a subset of the adjacent ports can be oriented to cause intermixing of compressed or pressurized gases exhausted from the bore at a location between the at least a subset of adjacent ports at the outer surface, thus providing at least one of: a reduction in muzzle movement, reduction in sound and reduction in recoil effect, when a fired round traverses along the axis. 
     Additional features, advantages, and aspects of the present disclosure may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the present disclosure and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the present disclosure as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the present disclosure, are incorporated in and constitute a part of this specification, illustrate various aspects, advantages and benefits of the present disclosure, and together with the detailed description, serve to explain the principles of the present disclosure. In addition, those skilled in the art will understand that, according to common practice, the various features of the drawings discussed below are not necessarily drawn to scale, and that dimensions of various features and elements of the drawings may be expanded or reduced to more clearly illustrate the embodiments of the disclosure. 
         FIG. 1  is a perspective view of a muzzle brake assembly, according to one embodiment of the present invention; 
         FIG. 2  is a side elevational view, of a muzzle assembly, according to one embodiment of the present invention; 
         FIG. 3  is a perspective view of the muzzle brake assembly of  FIGS. 2-3 ; 
         FIG. 4  is a cross-sectional view of the muzzle brake assembly of  FIG. 2 ; 
         FIG. 5  is a side view of an additional enhancement of a muzzle brake assembly according to principles of the present invention; and 
         FIG. 6  is a cross-sectional view of the muzzle brake assembly of  FIG. 5 . 
         FIGS. 7A-7C  are photographs illustrating a pressure/shock wave created by a conventional muzzle brake assembly upon firing. 
         FIG. 7D  is a photograph illustrating a pressure/shock wave created by a muzzle brake assembly according to the principles of the present invention upon firing. 
         FIG. 8  is a graph illustrating the generated recoil Force vs. Time for the firing of a firearm using various conventional muzzle brakes or no muzzle brake versus a muzzle brake assembly according to the principles of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PRESENT DISCLOSURE 
     The aspects of the present disclosure and the various features and advantageous details thereof are explained more fully with reference to the non-limiting aspects and examples that are described and/or illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale, and features of one aspect may be employed with other aspects as the skilled artisan would recognize, even if not explicitly stated herein. Descriptions of well-known components and processing techniques may be omitted so as to not unnecessarily obscure the aspects of the present disclosure. The examples used herein are intended merely to facilitate an understanding of ways in which the present disclosure may be practiced and to further enable those of skill in the art to practice the aspects of the present disclosure. Accordingly, the examples and aspects herein should not be construed as limiting the scope of the present disclosure, which is defined solely by the appended claims and applicable law. Moreover, it is noted that like reference numerals represent similar parts throughout the several views of the drawings. The terms round and round of ammunition, as used herein, include a rimfire round, a centerfire round, shotgun shells including shot, slugs and other payloads, as well as other types of ammunition. 
     The present disclosure describes a muzzle brake assembly, for mounting on (or locating at) the muzzle of a firearm F, such as a centerfire or a rimfire firearm, for example, and is configured to reduce the felt recoil and reduce muzzle jump upon discharge. The firearm F can comprise a rifle, such as a bolt action rifle, semi-automatic or automatic rifle, such as an AR-15, M-4, ACR or other gas operated rifle, shotguns, and various other types of long guns and handguns. As shown in  FIG. 1 , in one example embodiment, the firearm F further can include a stock  10 , fire control  11  with a trigger  12 , and a barrel  13  having a first end  14  defining a chamber  15  in which a round of ammunition A is received, and a second or muzzle end  16  through which the round is discharged upon firing. The muzzle brake assembly according to the principles of the present invention may also produce an acoustic signature that is substantially equivalent to a firearm that does not contain a muzzle brake assembly. The resulting reduction in sound levels produced by the use of the muzzle brake assembly disclosed herein thus provides a significant improvement over currently available muzzle brakes, which tend to produce a loud sound signature, i.e., increased resulting sound and pressure levels experienced by shooters and others nearby upon firing. 
     The muzzle brake assembly configured according to the principles described by the present disclosure may provide at least the following benefits:
         An ability to reduce firearm recoil by redirecting the propellant gases.   Reduction or substantial elimination of muzzle movement upon discharge.   Lessening or maintaining the acoustic signature of the firearm close to non-braked levels.   Easily manufacturable by current machining practices thereby minimizing cost of manufacturing.       

     One example embodiment of a muzzle brake assembly configured according to principles of the disclosure, generally denoted by reference numeral  100 , is illustrated in  FIG. 1  as being received and/or releasably connected to the muzzle end  16  of the barrel  13  of the firearm.  FIGS. 2-4  illustrate the muzzle brake assembly  100  in further detail. As shown in  FIGS. 2-3 , the muzzle brake assembly generally includes a tubular body  101 , typically formed from a high strength material such as a metal or composite material, and will have open first and second or upstream and downstream ends  102   a / 102   b . The general shape of the body of the muzzle brake assembly  100  may be configured to be predominantly cylindrical, but other shapes may be employed, and the body should not be and is not limited to this cylindrical shape. The body of the muzzle brake assembly also includes an outer wall  103  and an inner wall  104  defining a longitudinally extending bore  135  ( FIG. 4 ). The muzzle brake bore  135  defined by the inner wall or surface  104  may be substantially concentric with the bore  145  of the barrel  13  of a firearm, along a generally centrally aligned axis  130 . The muzzle brake bore  135  accordingly is configured along the axis  130  to permit passage of a round of ammunition from the firearm barrel bore  145  along the axis  130  and out of the second end  102   b  of the body. 
     The muzzle brake assembly  100  is illustratively shown in  FIGS. 1 and 4  as located or attached to the muzzle end  16  of a firearm barrel  13  by attaching mechanism  136 . In one embodiment, the attaching mechanism may include a threaded arrangement  137  as shown in  FIG. 4 . Moreover, the muzzle brake assembly  100  may be detachably connectable to the end of the firearm barrel by other releasable locking or coupling connections as will be understood in the art. Alternatively, the muzzle brake assembly may be configured as a permanent or integrally formed part of a firearm barrel; typically located proximate the muzzle end of the barrel. 
     The muzzle brake bore  135  may be sized to substantially match a particular caliber of a firearm (i.e., diameters are substantially concentric) so that a round of ammunition of a particular caliber will pass through the bore  145  of the firearm barrel  140  and the muzzle brake bore  135 . Therefore, the diameter of the muzzle brake bore  135  defined by an inner surface of the bore of a firearm barrel  13  may be configured according to the caliber of the intended firearm with which it may be used. 
     In one aspect, the shape of the body  101  of the muzzle brake assembly  100  is generally symmetric with respect to the muzzle brake bore  135 . Additional possible profile shapes of the muzzle brake bore also can be used and can include circular, triangular, quadrilateral, pentagon, hexagon, heptagon, octagon, nonagon, decagon, dodecagon, and the like. The muzzle brake assembly  100  may also be configured with optional auxiliary features such as a wire cutter  120 , coupling mechanisms for connection to further accessories, or a standard muzzle crown geometry. 
     As shown in  FIGS. 2-4 , the muzzle brake assembly  100  will be configured with a plurality of gas exhaust ports  105  arranged about the circumference of the body  101  of the muzzle brake assembly  100  and communicating with the muzzle brake bore. As illustrated in  FIG. 4 , the ports  105  can be arranged in first and/or second, or upstream and downstream sets or groups of ports, and may be configured as extended cylindrical passages  106   a ,  106   b , or of a different slotted shape, each including an inlet  107  opening into the muzzle brake bore  135 , and an outlet  108  opening along the outer wall/surface  103  of the body. The ports  105  function as gas exhaust or venting passages projecting from and in communication with the inner volume defined by the muzzle brake bore  135  to permit an escape of gases caused by discharge of a round of ammunition from the firearm traversing through the muzzle brake bore  135 . The escaping gas is illustratively shown by arrows  125   a - 125   d  in  FIG. 4 . The number of ports  105  relative to the muzzle brake bore  135  may be varied as needed and can be used in determining the profile shapes of the muzzle brake bore. 
     In one aspect, the orientation of the ports  105  relative to the central axis  130  of the muzzle brake bore  135  generally may range from about 30° to about 150°, although other orientations also can be provided as needed. An about 45° to about 90° orientation may be preferred from a manufacturing perspective. However, other orientations also may be used to provide desired operational advantages, as described below. 
     Referring to  FIG. 2 , one or more annular or circumferential rings or recesses  112  can be formed in the outer wall/surface of the body at spaced locations there along. In one embodiment, these annular rings  112  can be formed as generally concave grooves  115   a ,  115   b  with a plurality of facets  110   a ,  110   b  being formed along adjacent upstream and downstream surfaces  116   a / 116   b  of the grooves  115   a ,  115   b . The facets  110   a ,  110   b  may be arranged in a plurality of pairs around the circumference of the outer surface of the muzzle brake assembly  100 . For example, as shown in  FIGS. 2-4 , facets  110   a ,  110   b  can comprise first and second facets, with the adjacent facets of each pair of facets can be formed at least partially opposing one another as shown in  FIGS. 2-3 . Other sets of paired facets are shown in the figures, but for explanation simplicity only reference to paired facets  110   a  and  110   b  is described; although the principles are generally the same for the other facets and associated ports and passageways. 
     The facets  110   a ,  110   b  may be formed at an angle in relation to the central axis  130  of the muzzle brake, which angle may be from about 30° to about 90° with respect to the control axis  130  of the brake. The ports  105  will be formed within the facets  110   a ,  110   b , with the passageways  106   a - 106   d  of the ports extending at a desired angle (i.e., in a range of from about 30° to less than 90° in relation to the axis  130 ) from their outlets  108  defined within the facets, to their inlet openings  107  communicating with the inner volume of the muzzle brake assembly  100  defined at least in part by the inner surface of the muzzle brake bore  135 . As indicated in  FIGS. 2-4 , in one particular embodiment, the ports generally will be positioned or oriented substantially perpendicular to the outward facing surfaces  113   a / 113   b  of their associated facets  110   a / 110   b . The orientation/angles of the facets further can assist in formation of the bores at desired angles with respect to the axis  130  of the muzzle brake, as well as in controlling spacing between the outlets of the ports as needed to achieve a desired intermixing of the gases exiting therefrom. 
     The angle of the surfaces  113   a / 113   b  ( FIG. 3 ) of the facets  110   a ,  110   b  may be substantially perpendicular to the axial axis  114   a / 114   b  of each passageway  106   a ,  106   b  for directing pressurized gas flows at substantially crossing directions as represented by arrows  125   a - 125   d . The angle “y” formed between the two axial axis&#39;  114   a ,  114   b  (and similarly between  114   c  and  114   d ) is illustrated as being about 90° in the embodiment of  FIG. 3 . However, this formed angle “y” may be at a non-90° angle that is more or less than 90° depending on the chosen angle of the passageways  106   a ,  106   d  in relation to the axis  130 . Each passageway, e.g., passageway  106   a  or  106   c , may be oriented at angle to an adjacent or opposing passageway, e.g., passageway  106   b  or  106   d  (and other paired passageways) so that the outlet openings  108  of each port formed along the outer surface of the body of the muzzle brake assembly  100  for each passageway (in this example, the surface being associated with a respective facet  110   a ,  110   b ) is at least partially facing and opposing an outlet opening of the adjacent passageway of a corresponding port (e.g., at the other port of each pair of ports). 
     Pressurized or compressed gases generated by firing a round of ammunition are vented or escape, at least in part, from the muzzle brake assembly  100  via the various paired sets of ports  105 , such as the ports  105  configured in adjacent facets  110   a ,  110   b . The mutually opposing ports  105  permit and foster an intermixing of the exiting compressed/pressurized gas flows (e.g., as represented by arrows  125   a - 125   d ) and tend to direct the gases away from the shooter from the paired ports  105 , thereby providing at least any one or more of: a reduction in muzzle movement, reduction in sound and reduction in recoil effect. In addition, the spacing and orientation of the adjacent facets  110   a / 110   b  along which the opposed pairs of ports  105  are located enables the facets  110   a / 110   b  opposite each port  105  to act as redirecting surfaces to help foster turbulence and create an eddying effect to the gases exiting the ports to further help direct the resultant pressure wave for such gases forwardly and away from the shooter as indicated in  FIG. 7D . In addition, as indicated in  FIGS. 2-3  and  5 - 6 , because of the pressure of the compressed gases generated by the firing of the round of ammunition generally being higher at the upstream or inlet end  136  of the bore  135  and decreasing as the gases proceed down-bore, and the resultant differences in gas flow through paired ports  105  and their associated paired passageways, such as paired passageways  106   a - 106   b  and paired passageways  106   c - 106   d , due to such pressure differences, the opposed ports of each pair of ports can be provided with different diameters or sizes. 
     For example, one of the passageways, in this example, the downstream passageways  106   b  and  106   d  can be configured with a diameter that is the same or greater than its respective paired passageway  106   a  and  106   c . That is, due to gas dynamics, the ports  105  having their inlets  107  ( FIG. 4 ) and associated passageways (e.g., passageways  106   b ,  106   d ) closer to the distal end  102   b  of the brake body (the end where the round exits the muzzle brake assembly  100 ) of each paired set of ports is configured with a diameter that is greater than or equal to the diameter of the its corresponding/associated paired port nearer the proximal end  102   a  of the brake body (the end where a round enters the muzzle brake assembly  100  thus the gas flow pressures are at their highest in operation). 
     This diameter difference relationship of paired ports and is illustrated in  FIGS. 2-3 ; and the diameter difference relationship of the corresponding paired passageways (e.g.,  106   a / 106   b  and  106   c / 106   d ) generally is illustrated in  FIG. 4 . The diameter difference relationship of paired ports/passageways may compensate variances in flow rates for the escaping pressurized gases to provide for a substantially equivalent gas mass for each of the opposing flows because of the direction of flow of the compressed gases along the bore  135  of the muzzle brake assembly  100 , with the gases exiting the upstream ports/passageways potentially being of a higher pressure. As a result, the resultant direction and shape of the pressure wave of the gases exiting the ports generally is changed such that the gas flow and the corresponding sound signature or wave is in a direction away from the shooter as shown in  FIG. 7D , rather than being directed rearwardly as can occur with conventional muzzle brakes, such as shown in  FIGS. 7A-7C . The ratio of diameters of paired ports/passageways can be from about 3-4:1, within the distal port (the downstream port of each pair of ports which is further away from the shooter) upstream or paired having a longer diameter or size versus its proximal port/passageway, or greater to about 1:1 (distal port to paired proximal port/passageway), and with about 2:1 (distal port to paired proximal port/passageway) being a preferred ratio. 
     The “brake” effect accomplished by the muzzle brake assembly according to the present invention generally is created by the redirecting of the propellant gases in directions that generally are not generally parallel to the axis  130  of the barrel and muzzle brake bore  135 . To this end, the force vectoring produced by the propellant gases is angled away from the bore of the firearm barrel and muzzle brake assembly axis  130  as indicated in  FIG. 4 , i.e., as noted, the direction and shape of the resultant pressure wave can change, from being generally concave and expanding toward the shooter as shown in  FIGS. 7A-7C , to a generally convex, forwardly moving shape wave as shown in  FIG. 7D . This redirection of the propellant gases changes the force response of the gases as related by Newton&#39;s third law. Also, the kinetic energy, associated with the escaping gases is directed radially away from the barrel and muzzle brake centerline axis along substantially equally spaced radial paths so as to resist muzzle lift or jumping or other movement of the muzzle end of the barrel upon firing of the round of ammunition. Therefore, the energy available for transmission to the shooter via recoil also can be reduced. 
     In addition, the intermixing of the gas flows caused by the orientation of the outlets  108  ( FIGS. 3-4 ) of each of the ports  105  tends to disrupt the pressure wave created by the exiting pressurized gases, which can cause a reduction and/or a redirection of this pressure wave in a direction away from the shooter, for example, forwardly with respect to the axis of the muzzle brake assembly and firearm barrel. Such a forwardly redirected pressure wave is shown in  FIG. 7D . As a result, the acoustic signature may be reduced, or maintained to a substantially lower acoustic level (such as substantially the same decibel level, or less) as if no brake was being used or as compared to a standard brake design, by redirecting the propellant gases into opposing or nearly opposing or nearly opposing directions from different longitudinal locations along the length of the muzzle brake assembly  100 . Still further, by redirecting the radial gases from different longitudinal locations, the spherical pressure waves generally produced from the various locations are destructively additive or mutually cancelling, thereby lessening the net effective pressure wave. Therefore, the acoustic signature as experienced by the shooter and those in proximity may be reduced or approaching a level as if no muzzle brake assembly was being used, depending on the geometry of the longitudinal and radial gas exits. 
     As illustrated in the graph of Force versus Time provided in  FIG. 8 , a resulting reduction in sound may be achieved by an effective cancellation (at least in part) of the sound waves exiting or caused by the escaping compressed/pressurized gases being directed at or crossing with the gas flows exiting from the opposed ports  105  of adjacent facets  110   a ,  110   b  (and similarly all the other paired mutually opposing ports) of the muzzle brake assembly  100 , creating the intermixing of the gases such as shown in  FIG. 7D . This intermixing of the gases causes a disruption of the pressure wave(s) created by the escape of the pressurized gases, reducing the sound levels created thereby, and, to some extent, further cause the direction of such gases away from the shooter, e.g., forwardly along the body of the muzzle brake assembly  100 , which can additionally lessen the sound levels experienced by the shooter.  FIGS. 7A-7C  sequentially show the creation of pressure waves of gases as generated by a conventional muzzle brake flowing/expanding rearwardly toward the shooter. As indicated in these Figures, as the gases exit the conventional muzzle brake, they tend to expand outwardly and rearwardly ( FIG. 7B ) in a concave, cone shape focused toward a rearward direction along the firearm barrel.  FIG. 7C  further shows the rapidly expanded, enlarged pressure wave having a generally concave shape and moving rearwardly along the barrel of the firearm, i.e., toward the shooter. By contrast, the pressure wave exiting the muzzle brake according to the present invention shown in  FIG. 7D  exhibits an opposite or forward expansion and movement of gases, expanding away from the shooter, in a generally convex configuration or pattern with respect to the shooter and potentially having a more limited expansion of the pressure wave shape or pattern. This provides a reduction in the sound signature associated with such a pressure wave. 
     The following table discusses the differences in measured sound levels (by decibel) of a conventional AR15 style rifle (DPMS A2) fired (both with and without a flash hider) without a muzzle brake, fired with a .308 Miculek muzzle brake, an AAC Blackout muzzle brake, and a muzzle brake formed in accordance with the principles of the present invention (labeled “Cancelation Brake” in the table below. As can be seen in the table below, there was a significantly lower sound signature achieved with the muzzle brake assembly according to the principles of the present invention versus the other muzzle brakes tested. 
     
       
         
           
               
               
               
               
               
               
             
               
                   
               
               
                 Shooters 
                 DPMS A2 - 
                   
                 308 
                 Cancellation 
                 AAC 
               
               
                 left ear 
                 flash hider 
                 no brake 
                 Miculek 
                 Brake 
                 Blackout 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Shot 1 
                 158 
                 159.6 
                 171 
                 166.5 
                 171.2 
               
               
                 Shot 2 
                 158.4 
                 159.4 
                 170.5 
                 166.7 
                 170.4 
               
               
                 Shot 3 
                 158.9 
                 159.6 
                 170.6 
                 166.5 
                 170.7 
               
               
                 Shot 4 
                 158.4 
                 159.6 
                 170.5 
                 166.6 
                 170.3 
               
               
                 Shot 5 
                 158.6 
                 159.4 
                 171 
                 166.2 
                 170.5 
               
               
                 dB (avg) 
                 158.5 
                 159.5 
                 170.7 
                 166.5 
                 170.6 
               
               
                   
                 Diff from A2 
                 1.1 
                 12.3 
                 8.0 
                 11.1 
               
               
                   
                 dB 
               
               
                   
               
            
           
         
       
     
     Moreover, the exiting of the compressed gases at an angle not perpendicular to the axis  130  also substantially reduces muzzle movement (i.e., muzzle jump). Reduction of muzzle movement often may be important to a shooter in a critical situation, such as to reacquire a target quickly, for example. Flash hiders such as referenced in the table above, while providing reduction of a visible flash of burning gases exiting the barrel (and possibly some minor sound reduction) generally are not designed to address the reduction of recoil and/or muzzle jump/movement as are muzzle brakes. With the present invention, in addition to a reduction in acoustic signature or sound levels from firing, the mutually opposing configuration of ports  105  accordingly further substantially reduces both muzzle jump/movement, as well as the peak recoil as felt by a shooter. According to laboratory tests, this peak recoil reduction may be as much as about 25%, as compared with using no muzzle brake assembly. A graphical representation of the results of such peak recoil reduction tests is shown in  FIG. 8 . As the graph of  FIG. 8  indicates, a range of peak recoil force reduction may be reduced by about 5% to about 40%, with typical achievable range of about 20% to about 25% reduction, compared with using no muzzle brake assembly or with the use of a flash hider only. These tests employed calibers such as .30-06 SPRG and .308 WIN. However, other calibers may achieve similar results. The peak recoil force reduction further may be related to the caliber used for a particular application. 
     Alternate configurations of the ports  105  ( FIGS. 2-6 ) also may be possible to give different recoil reduction effects, sound reduction effects and/or possible shifts in resulting frequencies. For example, the ports  105  of each pair of ports may be circumferentially offset from one another so that they are not directly opposing one another, rather by offsetting the ports  105  circumferentially somewhat by a predetermined distance (such as circumferentially offsetting/rotating facet  110   a  in relation to facet  110   b , and similarly, the other facets around the grooves  115   a ,  115   b ), and/or varying the sizes of and/or gas volumes permitted through each of the ports to provide the desired recoil reduction and reduction of sound volume and/or frequencies (lower or higher). In addition, the ports of each pair of ports may be formed in an opposing relationship, but the pairs of ports of the upstream set or group of ports formed along the first or upstream annual ring  115   a  may be offset from the pairs of ports of the downstream set(s) or groups of ports formed along the second or downstream annular ring  115   b , and/or a third annular ring  115   c  shown in  FIGS. 5-6 . 
     Moreover, in one alternate aspect, the principles herein may be achieved without the use of facets. The relative configuration of mutually opposing ports  105  may be achievable without use of facets and/or the annular rings or circumferential grooves  115   a ,  115   b.    
     Still further, the diameter of the ports  105  and associated passageways (e.g., passageways  106   a - 106   c ), may be sized in accordance with or based on the amount of expected gasses that may be produced by a particular firearm and associated ammunition, so that venting rate of the gasses is appropriate for the intended ammunition and firearm. Moreover, the number of opposing paired ports  105  may be decreased or increased based on caliber size and/or type of ammunition expected, while maintaining effective recoil reduction, sound reduction, and/or acceptable reduction in muzzle movement. This may be accomplished by changing the number of ports or increasing/decreasing the number of concentric ringed sets or circumferential grooves. 
       FIG. 5  is a side view and  FIG. 6  is a cross-sectional view of an additional embodiment exemplary muzzle brake assembly, configured according to principles of the disclosure, generally denoted by reference numeral  200 . The muzzle brake assembly  200  is shown configured with three concentric rings or grooves  115   a ,  115   b ,  115   c . The ports  105  of groove  115   c  and its associated facets  110   a ,  110   b  are shown as being offset circumferentially as compared with the ports  105  and its respective facets  110   a ,  110   b  of grooves  115   a  and  115   b . This configuration may provide for ease of manufacturing of the associated passageways that extend from an outer surface, such as the respective associated facets of the muzzle brake assembly  200 , to the muzzle brake bore  135 , and this configuration may also provide for suitable orientations of the passageways so that they do not interfere with one another in the interior portions of the body of the muzzle brake assembly  200 , for example. 
     The foregoing description generally illustrates and describes various embodiments of the present invention. The examples given above are merely illustrative and are not meant to be an exhaustive list of all possible designs, aspects, applications or modifications of the present disclosure. It will, therefore, be understood by those skilled in the art that while the present disclosure has been described in terms of exemplary aspects, the present disclosure can be practiced with various changes and modifications which can be made to the above-discussed construction of the present invention without departing from the spirit and scope of the invention as disclosed herein, and that it is intended that all matter contained in the above description or shown in the accompanying drawings shall not to be taken in a limiting sense. 
     Furthermore, the scope of the present disclosure shall be construed to cover various modifications, combinations, additions, alterations, etc., to the above-described embodiments, which shall be considered to be within the scope of the present invention. Accordingly, various features and characteristics of the present invention as discussed herein may be selectively interchanged and applied to other illustrated and non-illustrated embodiments of the invention, and numerous variations, modifications, and additions further can be made thereto without departing from the spirit and scope of the present invention as set forth in the appended claims.