Recoil apparatus for a firearm

[0002] The present invention concerns a device useful to dampen the recoil experienced by a shooter upon firing a firearm.

[0003] Gun recoil is experienced when using virtually any firearm. Recoil from such firearms can cause the shooter to flinch, the muzzle of the firearm to deflect and for large caliber firearms, discomfort or pain. Such movements generally result in reduced accuracy. Accordingly, it is desirable to reduce recoil to improve accuracy and decrease shooter discomfort.

[0004] Recoil devices operable to reduce the amount of recoil transmitted to the shoulder of a shooter are well known in the art. For example, a commonly used recoil system employs one or more compression springs disposed inside the butt stock of a firearm. Upon firing, the butt stock slides rearward toward a shoulder-engaging portion of the firearm, compressing the springs and thereby damping the recoil effect. Other state-of-the-art recoil-reducing devices employ pneumatic air chambers and hydraulic cylinders to reduce the effect of gun recoil.

[0005] Despite these prior inventions, there still is a need for recoil damping devices, and methods for their use, that provide for greater reduction in recoil experienced by a shooter.

[0006] The present invention is directed to features and aspects of a recoil reducing apparatus for a firearm, both alone and in various combinations and sub-combinations with one another, which are set forth in the claims below.

[0007] According to one representative embodiment, a recoil apparatus for a firearm comprises a magnetic recoil damping system and a housing for housing the system. In particular embodiments, the damping system comprises first and second magnets, which are positioned in a repelling configuration relative to each other. The first and second magnets desirably comprise permanent magnets, although in other embodiments the first and second magnets may comprise electro-magnets. An optional biasing element, such as a compression spring, may be coupled to one of the first and second magnets.

[0008] According to another representative embodiment, a recoil apparatus is provided for a firearm comprising a base portion and a shoulder-engaging portion that is movable with respect to the base portion in response to the recoil of the firearm upon firing. First and second magnets, which are desirably disposed in the base portion, are positioned in a repelling configuration relative to each other to produce magnetic repulsion forces that bias the base portion in a direction against the recoil of the firearm. Thus, upon firing of the firearm, the magnetic repulsion forces dampen the recoil energy of the firearm, and therefore reduce the amount of recoil energy that is transmitted from the shoulder-engaging portion to the shoulder of a user.

[0009] If desired, a compression spring may be provided to further dampen the recoil of the firearm. In a disclosed embodiment, the spring is axially aligned with and coupled to one of the first and second magnets and is configured to bias the base portion against the recoil of the firearm. Thus, in this manner, the magnetic repulsion forces produced by the first and second magnets in cooperation with the compression spring serve to reduce the amount of recoil energy that is transmitted from the shoulder-engaging portion to the shoulder of a user.

[0010] In addition, a third magnet may be disposed in the base portion for producing a magnetic attractive force that restricts the shoulder-engaging portion from moving relative to the base portion when the firearm is being aimed prior to firing. In a specific implementation of the invention, the third magnet is magnetically attracted to an end piece that is coupled to the end of the base portion. The end piece defines an opening that is dimensioned to slidably receive a spacer member of the shoulder-engaging portion upon firing of the firearm. When the firearm is not undergoing recoil, the first magnet is held in front of the opening by way of its magnetic attractive force, to prevent movement of the spacer member through the opening, and therefore prevent movement of the shoulder-engaging portion relative to the base portion.

[0011] The end piece may have a pair of magnetic members disposed thereon for magnetically attracting the third magnet. In addition, an adjusting mechanism may be provided for varying the fore-aft position of the third magnet relative to the magnetic members, and therefore the strength of the magnetic attractive force that prevents movement of the shoulder-engaging portion relative to the base portion. Operating the adjustment mechanism to move the third magnet away from the magnetic members decreases the strength of the magnetic attractive force, which in turn decreases the amount of recoil energy that is transmitted to the shoulder of a shooter. Conversely, operating the adjustment mechanism to move the third magnet closer to the magnetic members increases the strength of the magnetic attractive force, which in turn increases the amount of recoil energy that is transmitted to the shoulder of a shooter.

[0012] In another representative embodiment, a recoil apparatus for a firearm comprises a first magnet disposed in a base portion of the firearm. The first magnet is configured to produce a magnetic force that retains a shoulder member of the firearm and the base portion from moving relative to each other when the firearm is being aimed prior to firing. Upon firing of the firearm, motion of the shoulder member is arrested by the shoulder of a shooter and the recoil of the base portion overcomes the magnetic force of the first magnet, thereby allowing the base portion to move to the recoil position. In addition, an optional adjustment mechanism may be provided for varying the strength of the magnetic force and therefore the amount of recoil that is transmitted from the shoulder member to the shoulder of the shooter.

[0013] According to yet another representative embodiment, a recoil apparatus for a firearm comprises a magnet system disposed in a base portion of the firearm. The magnet system comprises a first magnet, a second magnet, and a third magnet. The first magnet is configured to prevent relative movement between a shoulder member of the firearm and the base portion when the firearm is being aimed prior to firing. The second and third magnets are longitudinally aligned in a repelling configuration to produce repulsion forces that dampen the recoil forces transmitted from the shoulder member to the shoulder of a shooter upon firing of the firearm.

[0014] According to still another embodiment, a recoil apparatus is provided for a firearm comprising a base portion and a shoulder member coupled to and movable with respect to the base portion. The recoil apparatus comprises means for magnetically reducing firearm recoil energy that is transmitted from the shoulder member to the shoulder of a user. The recoil apparatus also may include means for magnetically retaining the base portion from moving relative to the shoulder member when the firearm is not undergoing recoil.

[0015] These and other features of the invention will be more fully appreciated when the following detailed description of the invention is read in conjunction with the accompanying drawings.

[0016] FIG. 1 is a partial perspective view of a firearm having a recoil apparatus constructed in accordance with one embodiment of the invention.

[0017] FIG. 2 is an enlarged fragmentary longitudinal vertical section of the butt end of the stock of the firearm of FIG. 1 showing the recoil apparatus prior to firing.

[0018] FIG. 3 is a longitudinal vertical section view similar to FIG. 2 showing the recoil apparatus in a recoil position.

[0019] FIG. 4 is an enlarged exploded perspective view of the recoil assembly and the stock of the firearm of FIGS. 1-3.

[0020] FIG. 5 is an enlarged sectional view taken along line 5—5 of FIG. 2 showing the spacer member positioned in the opening of the end piece.

[0021] FIG. 6 is a sectional view taken along line 6—6 of FIG. 2.

[0022] FIG. 1 illustrates a firearm, indicated generally at 10, which may comprise, for example, a shotgun or a rifle. Firearm 10 in the illustrated configuration comprises an elongate stock portion, or butt stock, 12, having a lower base portion 14 and an upper comb portion 16. Base portion 14 is fitted with a recoil apparatus, indicated at 17, constructed in accordance with embodiments of the invention, for absorbing the recoil of the firearm 10.

[0023] Referring also to FIGS. 2-5, the recoil apparatus 17 in the illustrated embodiment comprises a shoulder member 18 (also referred to herein as a shoulder-engaging portion in other embodiments), which has a forward mounting plate 26, a butt pad 28 and a spacer member 30 extending forwardly toward the firearm barrel from the mounting plate 26. The spacer member 30 may be secured to the mounting plate 26 as desired, such as by using fasteners, including screws 25 as illustrated. The butt pad 28 desirably comprises a resilient material, such as rubber, as generally known in the art.

[0024] A key 32 may be coupled to the forward end of the spacer member 30. The key 32 is positioned to bear against a first magnet 38 (described below) disposed in the base portion 14. The shoulder member 18 is movable longitudinally with respect to the base portion 14 from a first, extended position (FIG. 2) to a second, retracted or recoiled position (FIG. 3) in response to the recoil of the firearm 10 upon firing, as described in greater detail below.

[0025] As best shown in FIGS. 2 and 3, an end piece, or end plate, 20 is secured to the end of the base portion 14 using any suitable method, such as with fasteners, including the illustrated mounting screws 46. The end piece 20 defines a centrally located opening, or aperture, 24 (as best shown in FIGS. 4 and 5), which is dimensioned to permit passage of the spacer member 30 therethrough. As best shown in FIGS. 2 and 3, the base portion 14 in the illustrated embodiment is formed with a recess 58 and axial, substantially parallel bores 48, 50, and 52, which extend from the recess 58 toward the forward end of the firearm 10. Recess 58 is dimensioned to slidably receive a portion of the spacer member 30. Thus, as shown in FIG. 3, when the shoulder member 18 is moved to its retracted position in response to the recoil of the firearm 10, the spacer member 30 extends through the opening 24 in the end piece 20 and into the recess 58.

[0026] In the illustrated embodiment, upper bore 48 extends into the base portion 14 a greater distance than do bores 50 and 52. Upper bore 48 also may be lined with a sleeve 54. The lower bore 52 can be similarly lined with a respective sleeve 56. The sleeves 54, 56 can be made from any suitable material, such as, for example, metals or alloys, including steel or aluminum. The sleeve 54 and the sleeve 56 slidably receive guide rods 34 and 36, respectively, which may be secured to a surface 49 of the spacer member 30. Guide rods 34 and 36, and bores 48, 50, and 52 are substantially parallel to the barrel of the firearm 10. Bore 50 in the illustrated embodiment comprises a stepped cylindrical bore, having a first, larger diameter bore 50aand a second, smaller diameter bore 50b.

[0027] As further shown in FIGS. 2 and 3, a magnet system includes a magnet assembly 37 disposed in the bore 50a. Illustrated magnet assembly 37 comprises a cylindrical housing 60, which is formed with recesses in a forward end portion 41 and a rear end portion 43. A first magnet 38 is disposed in the recess formed in the rear end portion 43 of the housing 60. A second magnet 40 is disposed in the recess formed in forward end portion 41 of the housing 60. Other configurations for the magnet assembly 37 and housing 60 also may be used. For example, in an alternative embodiment, first and second magnets 38, 40 may be disposed in separately formed first and second cylindrical housings that are secured to each other in a conventional manner, such as by welding or bolting the housings to each other. In another alternative embodiment, the first magnet 38 and the second magnet 40 may be secured to opposite ends of a shaft without the use of a housing for either magnet.

[0028] The second magnet 40 is substantially axially aligned with a third magnet 42, positioned forwardly of the second magnet 40 within the bore 50a. The second magnet 40 and the third magnet 42 are positioned in a repelling configuration relative to each other so that the third magnet 42 is urged forwardly (as indicated by arrow E in FIGS. 2 and 3) and the second magnet 40 is urged rearwardly (as indicated by arrow F in FIGS. 2 and 3). An inner sleeve 76, desirably made of a substantially non-magnetic material (e.g., stainless steel), may be disposed in the bore 50ato maintain the second and third magnets 40, 42, substantially axially aligned.

[0029] Third magnet 42 in the illustrated embodiment is supported in a cylindrical housing 64. A shaft 66 extends from the forward end of the housing 64 and into the smaller diameter bore 50b. Secured to the forward end of the shaft 66 within the bore 50b, opposite the housing 64, is an end piece 72. A spring-retaining member 70 and elastomeric members in the form of rubber grommets 78a, 78bare slidably disposed on the shaft 66 proximate the forward end of the bore 50a. A biasing element, such as a compression spring 68, is operably positioned in bore 50a. The illustrated embodiment includes compression spring 68 concentrically disposed about shaft 66 and extending between the forward end of the housing 64 and the rubber grommets 78a, 78b. The biasing force of spring 68 urges spring-retaining member 72 forwardly against an adjacent surface 74 of the bore 50aand the third magnet 42 rearwardly toward the second magnet 40. Shaft 66 is moveable relative to the spring-retaining member 70 to permit compression and subsequent expansion of spring 68 in response to the firearm recoil.

[0030] As best shown in FIGS. 4 and 5, magnetic members 22a, 22bare mounted to forward surface 21 of end piece 20 for magnetically attracting the first magnet 38. The illustrated embodiment has magnetic members 22a, 22bon diametrically opposed sides of the opening 24. Magnetic members 22a, 22bare made of any suitable magnetic material that is attracted to a magnet. For example, the magnetic members 22a, 22bmay be made of steel or any of other various ferromagnetic materials. Alternatively, the end piece 20 also can be made of a suitable magnetic material for magnetically attracting the first magnet 38, in which case the magnetic members 22a, 22bwould not be used.

[0031] Under static conditions, that is, when firearm 10 is not recoiling after being filed, the magnetic attractive force produced by the first magnet 38 and the magnetic members 22a, 22bretains the first magnet 38 in its desired static position, such as in contact with the magnetic members 22a, 22b(as illustrated in the figures and indicated by arrows C and D in FIGS. 2 and 3). In this position, the first magnet 38 extends across the opening 24 of the end piece 20 (as best shown in FIG. 5) and therefore prevents forward movement of the spacer member 30 relative to the base portion 14 through the opening 24.

[0032] The strength of the magnetic attractive force between by the first magnet 38 and the magnetic members 22a, 22bdesirably is sufficient to prevent any relative movement between the shoulder member 18 and the base portion 14 when the firearm 10 is being handled or aimed prior to firing. When firearm 10 is fired, gun recoil forces the base portion 14 in the rearward direction (as indicated by arrow B in FIG. 2) toward the shoulder member 18, which is restrained against movement since it bears against the shooter's shoulder. The energy imparted to the base portion 14 upon firing overcomes the magnetic attractive force between the first magnet 38 and the magnetic members 22a, 22b, causing key 32 to force the first magnet 38 away from the magnetic members 22a, 22band allowing the spacer member 30 to pass through the opening 24 in the end piece 20 and into the recess 58 in the base portion 14. Some recoil energy is dissipated in separating or “breaking” the magnetic attachment of the first magnet 38 and the magnetic members 22a, 22b.

[0033] Second and third magnets 40, 42, respectively, along with the spring 68, serve as recoil reducers for reducing the recoil that is transmitted from the shoulder member 18 to the shoulder of a shooter. More specifically, as illustrated in FIGS. 2 and 3, as the base portion 14 moves rearwardly, the magnet assembly 37 is restrained against rearward movement by the spacer member 30. This causes the magnet assembly 37 to slide forwardly relative to the bore 50a, toward the third magnet 42, and against the bias of the magnetic repulsion forces produced by the second and third magnets 40, 42 and, if a second recoil reduction device is included, such as spring 68, against the biasing force of the spring 68 (FIG. 3). As the second magnet 40 is moved toward the third magnet 42, the third magnet 42 is driven forwardly relative to the bores 50aand 50b, thereby compressing the spring 68. In this manner, recoil energy is absorbed by compression of the spring 68 and by the repulsive forces produced by the second and third magnets 40, 42, as the base portion 14 moves toward the shoulder member 18. The strength of the second and third magnets 40, 42 are selected so that when the base portion 14 reaches the fully recoiled position, as shown in FIG. 3, there remains a slight separation between the second and third magnets 40, 42, respectively.

[0034] For working embodiments, each of the first, second and third magnets 38, 40 and 42 have a magnetic holding force of about 58 lbs. to about 115 lbs., with about 100 lbs. being a specific example, although magnets with greater or lesser holding forces also may be used. Suitable magnets are commercially available from, for example, Bunting Magnetics Co. of Newton, Kans. under Product Nos. BM2105RE, BM2106RE and BM2107RE.

[0035] Upon firing of the firearm 10, the shooter experiences some recoil as the energy of the base portion 14 overcomes the magnetic attractive force between the first magnet 38 and the magnetic members 22a, 22band begins to move rearwardly toward the shoulder member 18. Consequently, recoil transmitted to the shoulder of the shooter as a result of the initial movement of the base portion 14 depends, in part, on the strength of the magnetic attractive force between the first magnet 38 and the magnetic members 22a, 22b. Thus, to enable a shooter to easily adjust the amount of recoil transmitted to his or her shoulder, an adjustment mechanism may be provided for varying the position of the first magnet 38 fore and aft relative to the magnetic members 22a, 22b, and therefore the strength of the magnetic attractive force between the first magnet 38 and the magnetic members 22a, 22b.

[0036] As best shown in FIG. 4, an adjustment mechanism according to one embodiment comprises a post 116 that extends from the rear surface of the key 32 and into the forward end of a bore 118 formed in the spacer member 30. The opposite end of the bore 118 is threaded to receive a cooperatively threaded adjusting screw 114, which bears against the end of the post 116. In the illustrated embodiment, access to the adjusting screw 114 is provided through an opening 124 formed in the butt pad 28 and the mounting plate 26 (FIGS. 2-4). Otherwise, screws 25 are readily removed to detach the butt pad 28 and the mounting plate 26 from the spacer member 30 to gain access to the adjusting screw 114. Spacer member 30 may be provided with a transversely extending, threaded opening in one side thereof for receiving a threaded set screw 126 (FIG. 4), which when tightened, bears against the side of the post 116 to secure the key 32 against movement once the position of the adjusting screw 114 is set.

[0037] When the first magnet 38 is in contact with the magnetic members 22a, 22b(as shown in FIG. 2), the magnetic attractive force between the first magnet 38 and the magnetic members 22a, 22b, and therefore the holding force that prevents relative movement between the shoulder member 18 and the base portion 14, is greatest. However, adjusting the screw 114 in the forward direction (in the direction of arrow A) along the length of the bore 118, causes the key 32 to drive the first magnet 38 away from the magnetic members 22a, 22b, which causes a corresponding decrease in the magnetic attractive force between the first magnet 38 and the magnetic members 22a, 22b. Because the strength of the magnetic attractive force is decreased, less recoil is transmitted from the shoulder member 18 to the shoulder of the shooter upon firing the firearm 10. The first magnet 38 can be moved back toward the magnetic members 22a, 22bby adjusting the screw 114 in the rearward direction (in the direction of arrow B), which allows the first magnet 38 to move toward the magnetic members 22a, 22bunder the biasing force of the spring 68 and the repulsion force of the second and third magnets 40, 42, respectively.

[0038] Other forms of an adjusting mechanism for adjusting the magnetic force between first magnet 38 and magnetic members 22a, 22balso may be used. For example, in an alternative embodiment, adjusting screw 120 extends through the spacer member 30 and directly contacts the rear surface of the first magnet 38. Thus, in this configuration, key 32 is not used.

[0039] In alternative embodiments, the strength of the magnetic attractive force between the first magnet 38 and the magnetic members 22a, 22bcan be varied, for example, by selecting a first magnet 38 with greater or lesser magnetic strength, by varying the size of the magnetic members 22a, 22band/or by selecting magnetic members 22a, 22bwith higher or lower iron content.

[0040] Other configurations of a recoil apparatus may embody one or more features of the embodiment shown in FIGS. 1-6. For example, in one alternative embodiment, a magnet system comprises only two magnets. A first magnet is operable to prevent relative movement of the shoulder member 18 in a static mode in the same manner as the first magnet 38 of FIGS. 2-5. The first magnet is longitudinally aligned in a repelling configuration with a second magnet, which may be coupled to a biasing mechanism (e.g., a spring), such as shown in FIGS. 2-4. Thus, in this embodiment, the first magnet performs the function of both the first magnet 38 and the second magnet 40 of the embodiment shown in FIGS. 2-4, and the second magnet performs the function of the third magnet 42 of FIGS. 2-4.

[0041] In another embodiment, a magnet system comprises a pair of magnets arranged in a repelling configuration, such as the second and third magnets 40, 42, respectively, of FIGS. 2-4, to dampen the recoil of the firearm. In this configuration, the spring 68 and the first magnet 38 of the embodiment of FIGS. 2-4 can be optional. Desirably, the two magnets of the magnet system in this configuration are selected to produce repulsion forces that are sufficient to prevent relative movement between the shoulder member 18 and the base portion 14 when the firearm 10 is being aimed prior to firing and to adequately adsorb recoil energy upon firing without the use of a spring.

[0042] In still other embodiments, the first magnet 38 of FIGS. 2-5 may be used to prevent relative movement of the shoulder member 18 when the firearm is recoiling after being fired, as shown and described herein, but the second and third magnets 40, 42, respectively, of FIGS. 2-4 may be optional. In this configuration, a conventional recoil reducer (e.g., one or more compression spring(s), hydraulic cylinder(s), or a pneumatic air chamber) may be used in lieu of the spring 68 and the second and third magnets 40, 42, respectively, of the embodiment of FIGS. 2-4.

[0043] Moreover, although the first, second and third magnets 38, 40 and 42 of the illustrated embodiment are shown as being permanent magnets, this is not a requirement. For example, in alternative embodiments one or more of the first, second and third magnets 38, 40 and 42 may comprise an electro-magnet.

[0044] The upper comb portion 16 and the manner in which it is coupled to the base portion 14 may be conventional. Referring again to FIGS. 2 and 3, for example, upwardly extending, first and second dowel pins 84 and 86, respectively, are secured to the upper guide rod 34. The first and second pins 84 and 86, respectively, include lower threaded portions 96 and 98, respectively, which are threadedly received in respective threaded bores 100 and 102 provided in upper guide rod 34. The first and second dowel pins 84, 86, respectively, extend upwardly through slots 88 and 90, respectively, in the sleeve 54 and bores 92 and 94, respectively, in the upper portion of the base portion 14 and into the upper comb portion 16. The upper portions of the pins 84 and 86 are configured to receive the blade of a screwdriver (e.g., a flathead or Philips screwdriver) so that the pins 84 and 86 can be tightened into their respective bores 100, 102 of the upper guide rod 34.

[0045] The comb portion 16 is provided with first and second stepped bores 80 and 82, respectively, in which are fixedly received first and second sleeves 104 and 106, respectively, for slidably receiving the pins 84 and 86, respectively. Sleeves 104 and 106 may be securely positioned by suitable methods, such as by being glued into their respective bores 80 and 82 with a suitable adhesive, such as epoxy resin.

[0046] Referring to FIG. 6, the upper comb portion 16 also includes horizontally extending bores 108, which extend from the outer side surface of the comb portion 16 to each of the sleeves 104 and 106. Each sleeve 104, 106 is provided with a threaded opening 110 for receiving a cooperatively threaded set screw 112. Set screws 112 can bear against pins 84 and 86 to secure them against vertical movement within the comb portion 16. Thus, the height of the comb portion 16 relative to the base portion 14 can be adjusted by loosening the set screws 112, raising or lowering the comb portion 16 to the desired position, and thereafter tightening the set screws 112.

[0047] Comb portion 16 is operable to isolate a user's cheek from the recoil of the firearm upon firing, as generally known in the art. In the illustrated embodiment, for example, comb portion 16 remains in a fixed position and does not slide relative to the user's cheek since it is fixed relative to the shoulder member 18. Accordingly, the user's cheek, resting against the comb portion 16, is not subjected to the recoil movement of the firearm 10.

[0048] The foregoing description provides one specific configuration for a comb portion 16 and a mechanism for coupling the comb portion 16 to the base portion 14. Other configurations for the comb portion 16 or mechanisms for coupling the comb portion 16 to the base portion 14 also may be used without departing from the principles and scope of the invention. In other alternative embodiments, the comb portion 16 may be optional.

[0049] Recoil apparatus 17 can be easily installed in a new firearm during the manufacturing process or retrofitted in an existing unit. In one approach, for example, bores 48, 50 and 50 and recess 58 are formed in the base portion 14 of a firearm in a conventional manner. The components of recoil apparatus 17 are then installed in the firearm as shown in the figures.

[0050] The invention has been described with respect to particular embodiments and modes of action for illustrative purposes only. The present invention may be subject to many modifications and changes without departing from the spirit or essential characteristics thereof. I therefore claim as my invention all such modifications as come within the scope of the following claims.