Front and rear firearm sights

[0001] This invention relates to firearm sights, and shotguns in particular, whereby M4/M16 style sights can be utilized in conjunction with with an integral mounting rail.

[0002] Traditionally shotguns have been employed for wing shooting activities due to the pattern of projectiles that they produce which increase probability of hit upon moving aerial targets. With current law enforcement practice employing shotguns for applications where previously carbines would have been utilized, there is a cross-over use for a shotgun where it now is used in a manner similar to a carbine or rifle. With the demands for precision rifle style of fire as opposed to an area of fire, the need for precision tactical sights that perform similarly to those on a rifle or carbine is of paramount importance. Conventional shotgun sights are very rudimentary and predicated on a perfect mount of the firearm to the shooter so that they become unitary; and the shot pattern is where the shooter looks. Such sights which are largely bead sights mounted on the end of the barrel do not lend themselves to law enforcement or military use.

[0003] U.S. Pat. No. 5,966,825 to Paul Biemont (Oct. 19, 1999) discloses front sight for an assault rifle of the M16 variety. It is an A-shaped sight with a knob that is housed to rotate freely in a cross-member which then turns a threaded front sight post. It has two collars at the bottom of its limbs for fixing on a gun barrel.

[0004] Accordingly, several objects and advantages of my invention are to provide the use of an M16/M4 style sighting system for firearms, and shotguns in particular.

[0005] Another object of the invention is to provide a rear sight base that can utilize components from an M16 A2 style rear sight with the addition of a M-1913 picatinny style rail for the mounting of other sighting elements inline with the aperture style sights of the A2 sight components.

[0006] A further object of the invention is to provide a rear sight base that can utilize components from an M16 A1 style rear sight with the addition of a M-1913 picatinny style sight rail for the mounting of other sighting elements inline with the aperture style sights of the A1 sight components.

[0007] Another object of the invention is to provide a front sight base that can utilize components from an M16 A2 style front sight, and variants thereof.

[0008] A still further object of the invention is to provide a front sight base that can utilize components from an M16 A1 style front sight, and variants thereof.

[0009] Yet another object of the invention is to allow the use of an M16 A2 or A1 rear sight aperture with the use of an M16 A2 or A1 front sight post with the addition of a M-1913 picatinny style rail interposed so that auxilliary sighting components can be installed inline with the iron sight picture.

[0010] Still further objects and advantages will become apparent from a consideration of the ensuing description and accompanying drawings.

[0011] FIG. 1 is a perspective view of my invention assembled to a shotgun.

[0012] FIG. 2 is a perspective view of the preferred embodiment of the rear sight base and elevation adjustment knob of the present invention.

[0013] FIG. 3 is a side view of the rear sight base of the preferred embodiment of my invention.

[0014] FIG. 4 is a front perspective of the rear sight base of the preferred embodiment of my invention.

[0015] FIG. 5 is a perspective view of the front sight base and mounting pad of the preferred embodiment of my invention.

[0016] FIG. 6 is a cross-sectional side view of the front sight base of the present invention.

[0017] FIG. 7 is a perspective view of the preferred embodiment of the rear sight base with M16 A2 style sight components installed.

[0018] FIG. 8 is a cross-sectional side view of the rear sight base of my invention with sight components and the fasteners and dowel pin used to affix it to a shotgun.

[0019] FIG. 9 is a bottom perspective view of the front sight base of my invention with M16 A2 style sight components installed.

[0020] FIG. 10 is a partial perspective view of a shotgun barrel with mounting pad affixed and the front sight base of the preferred embodiment of the present invention.

[0021] FIG. 11 is a perspective view of the rear sight base of the present invention approximated to the top surface of shotgun receiver.

[0022] FIG. 12 is a a cross-sectional side view of the rear sight base of the preferred embodiment of the present invention approximated to a shotgun receiver.

[0023] FIG. 13 is a is a perspective view of an alternate embodiment of the rear sight base of the present invention which utilizes M16 A2 style windage components.

[0024] FIG. 14 is a perspective view of an alternate embodiment of the present invention with M16 A1 style sight components installed.

[0025] FIG. 15 is a perspective view of an alternate embodiment of the present invention to house M16 A1 style sight components.

[0026] 10 rear sight base

[0027] 10A rear sight base

[0028] 10B rear sight base

[0029] 12 rear sight elevation drum

[0030] 14 rear sight assembly

[0031] 16 front sight assembly

[0032] 18 shotgun

[0033] 20 elevation drum indexing bore

[0034] 22 threaded bore

[0035] 24 through window

[0036] 26 through bore

[0037] 28 rail dovetail profile

[0038] 30 front sight base

[0039] 32 mounting pad

[0040] 34 shotgun barrel

[0041] 36 threaded front sight post

[0042] 38 front sight detent

[0043] 40 front sight detent spring

[0044] 42 mounting pad cavity

[0045] 44 front retention pin bore

[0046] 46 rear retention pin bore

[0047] 48 crosscut

[0048] 48A crosscut

[0049] 50 threaded fastener

[0050] 50A threaded fastener

[0051] 50B threaded fastener

[0052] 50C threaded fastener

[0053] 52 front

[0054] 52A front

[0055] 54 shotgun receiver

[0056] 56 dowel pin

[0057] 58 blind recoil shoulder hole

[0058] 60 recoil shoulder dowel hole

[0059] 62 threaded rear sight housing

[0060] 64 rear sight windage screw

[0061] 64A rear sight windage screw

[0062] 66 selectable rear sight aperture

[0063] 66A selectable rear sight aperture

[0064] 68 threaded auxilliary hole

[0065] 68A threaded auxilliary hole

[0066] 70 threaded receptacle

[0067] 70A threaded receptacle

[0068] 70B threaded receptacle

[0069] 70C threaded receptacle

[0070] 72 base bore

[0071] 74 windage adjustment knob

[0072] 76 front cross-drilled hole

[0073] 78 rear cross-drilled hole

[0074] 80 fluted flange

[0075] 82 protective wing

[0076] 82A protective wing

[0077] 82B protective wing

[0078] 82C protective wing

[0079] 84 interrupted transverse rib

[0080] 86 bottom contour

[0081] 88 front sight guard

[0082] 88A front sight guard

[0083] 90 transverse rib

[0084] 92 windage adjustment wheel

[0085] 94 counterbored clearance hole

[0086] 94A counterbored clearance hole

[0087] 94B counterbored clearance hole

[0088] 94C counterbored clearance hole

[0089] 94D counterbored clearance hole

[0090] 94E counterbored clearance hole

[0091] 94F counterbored clearance hole

[0092] 96 through hole

[0093] 96A through hole

[0094] 96B through hole

[0095] 96C through hole

[0096] 98 rear sight windage screw hole

[0097] 100 windage detent cavities

[0098] 102 detent through hole

[0099] 104 detent blind hole

[0100] Front and rear sights for shotguns that provide the ability to utilize M16/M4 style sights within sight bases which can be affixed to the receiver and barrel of a shotgun. This sighting system brings and enhanced level of precision to a shotgun employing the modality of the present invention. Additionally the addition of an M-1913 style rail base to the rear sight assembly brings the added benefit of the ability to use an additional sighting collimator which conveys the benefit of a co-witnessed sight alignment. The use of M16/M4 style sights have proved their ruggedness and utility in military deployments since the 60s.

[0101] FIG. 1 is a perspective view which shows the front and rear sights of the preferred embodiment of the present invention which includes a rear sight assembly 14, and a front sight assembly 16, mounted to a shotgun 18. FIG. 2 shows a rear sight base 10, and a rear sight elevation drum 12, in a prespective view. Shown is the rear sight base 10 which has protective wing 82, and protective wing 82A, and extending from a front 52 surface a M-1913 style rail which extends towards the protective wings 82, and 82A of the rear sight base 10. Shown a interrupted transverse rib 84. Said rear sight base 10 contains a plurality of interrupted transverse ribs 84, spaced from front to back according to M-1913 specification, and commonly referred to as a Picatinny Rail. Said interrupted transverse ribs 84 are separated by a crosscut(s) 48. FIG. 2 shows elevation drum indexing bore 20 which are coaxially aligned around the threaded bore 22 of the rear sight elevation drum 12. Shown in FIG. 2 are through hole 96, and through hole 96A, which allow fasteners to attach directly to the top surface of a shotgun receiver. Also shown is through bore 26 for threaded rear sight housing 62 which is shown in FIG. 8. FIG. 3 is a side view of the rear sight base of the preferred embodiment of the present invention which shows a through window 24 for the rear sight elevation drum 12. Shown in side view is a bottom contour 86 which corresponds to the top surface of a shotgun receiver 54 which is shown in FIG. 11, with said bottom contour 86 approximated to the top surface of said shotgun receiver 54. FIG. 4 is a front perspective of the rear sight base 10 of the preferred embodiment of the present invention, and shows a rail dovetail profile 28, consistent with the dimensions specified in military specification, M-1913.

[0102] FIG. 5 is a perspective view of the preferred embodiment of the present invention that shows a front sight base 30, and a mounting pad 32, that serves for the interface between the front sight base 30 and a shotgun barrel 34, which is shown affixed in a partial perspective view in FIG. 10. Additonally shown is front sight guards 88, and 88A which are lateral to a threaded front sight post 36 which is shown in FIGS. 6 and 10. The bottom surface of said front sight base 30 is contoured to approximate the contour of to the shotgun barrel 34 (FIG. 10) to which it is affixed. FIG. 6 shows a cross-sectional side view of the front sight assembly 16, which includes the front sight base 30, a threaded front sight post 36, a front sight detent 38, and a front sight detent spring 40. Shown is a fluted flange 80 of the threaded front sight post 36. Additonally shown is a mounting pad cavity 42 within front sight base 30, front retention pin bore 44, and rear retention pin bore 46. FIGS. 5 and 10 show the mounting pad 32 front cross-drilled hole 76, and a rear cross-drilled hole 78.

[0103] FIG. 7 is a front perspective view of rear sight assembly 14 which shows the rear sight base 10 and a crosscut 48 which is repeated according to military specification, M-1913, from front 52 to rear, of rear sight base 10. Also shown is windage adjustment knob 74, rear sight elevation drum 12, and selectable rear sight aperture 66. FIG. 8 shows a cross-sectional side view of rear sight assembly 14 and threaded fastener 50, threaded fastener 50A, threaded fastener 50B, and threaded fastener 50C, which secure rear sight base 10 to a shotgun receiver 54, as viewed in FIG. 12. FIG. 8 shows counterbored clearance hole 94, counterbored clearance hole 94A, counterbored clearance hole 94B, and counterbored clearance hole 94C, for the threaded fasteners that secure rear sight base 10, to shotgun receiver 54. Additionally shown in FIG. 8 is a dowel pin 56, which serves the function of a recoil shoulder, as it is inserted within blind recoil shoulder hole 58 of rear sight base 10, and into a recoil shoulder dowel hole 60 within a shotgun receiver 54 in FIG. 12. FIG. 8 additionally shows a threaded rear sight housing 62, a rear sight windage screw 64, and a selectable rear sight aperture 66 which is the style of aperture used on an M4 or M16 style of firearm. Also visible in FIG. 8 is the rear sight base 10, and the rear sight elevation drum 12. FIG. 9 is a bottom perspective of the front sight base 30, and shows the mounting pad cavity 42 in bottom surface of front sight base 30. FIG. 10 is a partial perspecive veiw of a shotgun barrel 34 with the mounting pad 32 affixed, and the front sight base 30 of the preferred embodiment of my invention. FIG. 11 is a perspective view of the rear sight base of the preferred embodiment of the present invention approximated to the top surface of shotgun receiver 54. FIG. 12 shows a cross-sectional side view of rear sight base 10 approximated to shotgun receiver 54. Shown within shotgun receiver 54 are recoil shoulder dowel hole 60, and threaded auxilliary hole 68, and threaded auxiallary hole 68A. Additonally threaded receptacle 70, threaded receptacle 70A, threaded receptacle 70B, and threaded receptacle 70C, are shown are points of attachment for rear sight base 10 fasteners. Additonally shown in FIG. 12 are through window 24 for rear sight elevation drum 12 and base bore 72 for threaded rear sight housing 62.

[0104] FIG. 1 shows in perspective view the front and rear shotgun sights of the preferred embodiment of the present invention which comprises rear sight assembly 14 and front sight assembly 16. FIG. 2 shows the rear sight base 10 which is designed to receive the standard M16 A-2 rear sight components or their equivalents. The rear sight base 10 is fastened to a shotgun receiver such as the receiver shown in FIGS. 11 and 12 in perspective view, and in cross-sectional side view respectively with threaded fastener 50, threaded fastener 50A, threaded fastener 50B, threaded fastener 50C as shown in FIG. 8, which are threadably secured to corresponding threaded receptacle 70, threaded receptacle 70A, threaded receptacle 70B, and threaded receptacle 70C, within the top surface of the shotgun receiver 54. They are located within counterbored clearance hole 94, counterbored clearance hole 94A, counterbored clearance hole 94B, and counterbored clearance hole 94C, of rear sight base 10. It is utilizes the dowel pin 56 shown in FIG. 8 as a recoil shoulder which is inserted within blind recoil shoulder hole 58 within rear sight base 10, and then assembled within recoil shoulder dowel hole 60 within shotgun receiver 54 which is shown in FIG. 12. The rear of said rear sight base 10 serves to house M4/M16 A2 rear sight style components to created an windage and elevation adjustable rear sight assembly 14. The selectable rear sight aperture 66 is threadably inserted upon rear sight windage screw 64 shown in cross-section in FIG. 8. The windage adjustment knob 74 shown in FIG. 7 is fastened with a roll pin (not shown) to one end of rear sight windage screw 64, and rotates said screw when turned, with the resulting rotation creating translational movement of the selectable rear sight aperture 66 along the threaded body of rear sight windage screw 64. The resulting movement allows for windage adjustment of the rear sight aperture relative to the threaded front sight post 36 which is shown in FIGS. 6 and 10. FIG. 8 illustrates the elevation adjustment relationships of the rear sight assembly 14. Elevation adjustment of said selectable rear sight aperture 66 is accomplished by threaded rear sight housing 62 which is threadably inserted within the threaded bore 22 of the rear sight elevation drum 12. Inasmuch as rear sight elevation drum 12 is captured within through window 24 of rear sight base 10 threaded rear sight housing 62 moves up and down as rear sight elevation drum 12 is rotated creating elevation adjustment relative to the threaded front sight post 36 reference that is shown in FIGS. 6 and 10.

[0105] FIG. 5 shows the front sight base 30 and its mounting pad 32 which is fastened to a shotgun barrel 34 shown in FIG. 10. Front sight assembly 16 is affixed to mounting pad 32 with pins that are inserted through front retention pin bore 44 and rear retention pin bore 46 of front sight base 30 and through their corresponding mates front cross-drilled hole 76, and rear cross-drilled hole 78, within the mounting pad 32. Said front sight base 30 contains M4/M16 A2 style front sight components FIG. 6 shows threaded front sight post 36 which is threadably inserted within front sight base 30 to create elevation adjustment as it is rotated clockwise and counterclockwise. The front sight detent 38 engages a fluted flange 80 of the threaded front sight post 36. It is under positive pressure from front sight detent spring 40.

[0106] Elevation adjustment for a shotgun is to provide by either utilizing the rear sight elevation drum 12 to move the selectable rear sight aperture 66 up and down, or by rotating the threaded front sight post 36. Shotgun windage adjustment is accomplished by rotating windage adjustment knob 74 clockwise or clounterclockwise to move selectable rear sight aperture 66 left and right across the threaded front sight post 36 front reference. The combination of rear sight base 10, and front sight base 30 with their M4/M16 style components mounted to a shotgun 18 provides the sight picture familiar to individuals with either military service or experience with military firearms, Additionally it provides an adjustment system that is equally familiar to many individuals. The degree of sighting adjustment available by the preferred embodiment of the present invention brings precision to shotguns which heretofore have employed sighting systems with a limited degree of adjustment.

[0107] FIGS. 1, 2, 3, 4, 7, 8, 11, and 12 show a M-1913 style rail which is integral to rear sight base 10. The utility of this configuration is that optical sighting devices can be attached to the standard rail dovetail profile 28 with fasteners that are configured to utilize the crosscuts that are part of the M-1913 configuration. The ability to place a redundant sighting system in line with the aperture sighting system provided allows the utility of co-witnessing sight alignment to verify a sight picture. Additionally the durability provided by protective wings on rear sight assembly 14, and by front sight guards on front sight assembly 16 bring a increased degree of tactical capability to a shotgun to which the front and rear sights of the preferred embodiment of the present invention are affixed.

[0108] A1 Rear Sight Rail BaseDescription

[0109] Referring now to FIGS. 13, 14, and 15 wherein are depicted alternative embodiments of the present invention. FIG. 13 shows an alternate rear sight base 10A, which provides transverse rib(s) 90, which are separated by crosscut(s) 48A in a plurality from front 52A towards the back of the rear sight base 10A. These transverse rib(s) 90 are arranged in pattern consistent with M-1913 and are commonly referred to as a Picatinny Rail. Shown are protective wing 82B, and protective wing 82C, which are lateral to selectable rear sight aperture 66A. Also shown is windage adjustment wheel 92 which is affixed to rear sight windage screw 64A, and threadably inserted within selectable rear sight aperture 66A. Said windage adjustment wheel 92 has coaxially arranged detent through hole(s) 102. Said rear sight base 10A has a bottom contour that approximates the top surface of a shotgun receiver to which it may be affixed in a similar manner to the preferred embodiment of the present invention. Shown are counterbored clearance hole 94D, counterbored clearance hole 94E, and counterbored clearance hole 94F. Additionally shown are through hole 96B, and through hole 96C. Shown in FIG. 13 coaxially arranged about rear sight windage screw hole 98 are windage detent cavities 100 which permit the use of an A2 style windage adjustment knob 74, as shown in FIG. 7. A variant of rear sight base 10A is shown in FIG. 15, which is rear sight base 10B. The rear sight base 10B of FIG. 15 has a detent blind hole 104, which permits the use of a detent plunger (not shown) and a detent spring (not shown) to utilize windage adjustment wheel 92, which is shown assembled in FIG. 14. The assembly shown in FIG. 14 is consistent with what is commonly referred to as an M16 A1 sight. The rear sight base 10A of FIG. 13 provides a hybrid arrangement where an M16 style windage adjustment knob 74 is utilized to provide windage adjustment. Otherwise the function of the two sight bases, rear sight base 10A, and rear sight base 10B, are identical.

[0110] A1 Rear Sight Rail BaseOperation

[0111] The alternate embodiment of the rear sight base 10 of the preferred embodiment of the present invention rear sight base 10B permits the use of M16 A1 style rear sight components as opposed to the M16 A2 variety of the preferred embodiment. This rear sight provides only for windage adjustment. This is accomplished by rotating windage adjustment wheel 92 which is fixed to rear sight windage screw 64A that is threadably inserted within selectable rear sight aperture 66A, and provides movement of said rear sight aperture laterally as the windage screw is rotated by the windage adjustment wheel. Detented positions are maintained by a detent plunger (not shown) which is located within detent blind hole 104 of rear sight base 10B and is under spring pressure (not shown). There are coxially arranged detent through hole(s) 102 within A1 windage adjustment wheel 92 which allow for detented positions when an M16 A1 windage adjustment wheel 92 is used as shown in FIG. 14. The windage adjustment wheel provides discreet positions as it has coaxially arranged through hole(s) 102 about the center of rotation of rear sight windage screw 64A.

[0112] If A2 windage adjustment knob 74 as shown in FIG. 7 is utilized it is with rear sight base 10A which has coaxially arranged windage detent cavities 100 to accept a spring (not shown), and a plunger (not shown) housed within windage adjustment knob 74 which would operate in a fashion that it does on an M16 A2 rear sight assembly and on the preferred embodiment of the present invention.

[0113] The A1 rear sight base creates flexibility to the design of a shotgun sighting systems, and offers the ability of component elimination if the range of elevation adjustment offered by the A2 configuration with elevation adjustment available on the rear sight base is not desired.

[0114] Accordingly, it can be seen that the front and rear shotgun sights which are the object of the present invention afford a great degree of utility and modularity to the configuration options available in the production and utilization of shotguns, as they take advantage of a vast supply of M16/M4 style sight components which are readily available as well as variants of these standard parts.

[0115] Combinations of the front sight assembly with either the A2 style rear sight assembly or the A1 style with standard windage adjustment wheel or the modified version with an A2 windage knob offer at least three possible variations when mounted to a shotgun.

[0116] The use of an M16/M4 style sight picture with its rear aperture and front post design is familiar to vast numbers of shooters which have military experience or familiarity with the current assault rifles and carbines of the U.S. military. The outcome is that users will find the preferred embodiment of the present invention to be intuitive in use, and they will benefit from a greater level of precision in a shotgun sighting system than heretofore available.

[0117] With the prolific utilization of the shotgun modality in law enforcement, and the requirement to know the point of aim of each round fired, the front and rear sights of the present invention are ideal for law enforcement use.

[0118] Within the U.S. military the use of the front and rear sights which are the object of the present invention on shotguns would result in vastly reduced time to train soldiers in the use of shotguns, as they would already be familiar with the sight picture that my invention affords to them, as it is virtually the same sight picture as found on the M16 since its inception in the 1960's.

[0119] Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Various other embodiments and ramifications are possible within it's scope. For example,

[0120] The rear sight base can be fashioned to interface with various configurations of shotgun receiver to which it might be mounted;

[0121] the rear sight base can be made with and without a central groove down its length;

[0122] the size of the front and post and rear apertures can be modified for varying requirements;

[0123] the front and rear sight bases can be made of different materials, and different coatings to reflect the uses that they may be subject to; and

[0124] the width and thickness of the protective wings and front sight guards can be altered to provide a sight picture for differing requirements.

[0125] It will be apparent to those skilled in the art that many modifications and substitutions can be made to the preferred embodiment wihtout departing from the spirit and scope of the invention.

[0126] Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.