Firearm sight system

Firearm sight systems have an elongated mounting rail including a plurality of transverse bars separated by intervening transverse mounting location channels extending from a rearmost channel to a forwardmost channel, the rail having an elongated upper surface, the rail defining a pocket below the upper surface and at least in part forward of the rearmost channel, and a sight arm pivotally connected to the rail and movable between an elevated position angularly offset from the upper surface of the rail and a stowed position in which the sight arm occupies the pocket. At least a forward portion of the sight arm may be entirely below the upper surface of the rail when in the stowed position. The entire sight arm may be entirely below the upper surface of the rail when in the stowed position. The sight arm may pivot on a pivot axis below the upper surface of the rail.

FIELD OF THE INVENTION

The present invention relates to firearms, and more particularly to a firearm sight system that provides an integrated flip-up rear sight for AR-15/10 and M16/M4 rifle variants.

BACKGROUND OF THE INVENTION

The modern AR-15 style rifle platform is primarily comprised of MIL-SPEC (Military Specification) components originally derived from the M16A1/A2, M4A1 and M16A4 variants. Platforms include semi-automatic, burst and full-automatic fire control versions, as well as a multitude of caliber configurations. Most modern AR-15 components have retained either MIL-SPEC adherence and/or a close resemblance to the original 1956 Eugene Stoner and L. James Sullivan Armalite AR-15 design. All M16A1/A2, M4A1 and M16A4 variants retain absolute adherence to MIL-SPEC requirements, as these platforms are intended for applications in standardized military service.

The MIL-SPEC design utilizes an integrated Rear Sight, commonly referred to as an “Iron Sight.” Although the M4 variant is an exception, as it provides a Picatinny rail (MIL-STD-1913) for the mounting of its sight/optical aid. This type of configuration is commonly referred to as “Optic Ready,” inferring that a sight or optical device must first be installed on the firearm for accurate target acquisition. With the advent of the M4 configuration and further popularization of Upper Receiver designs without an integrated rear sight, a typical approach to provide sighting capabilities followed suit with the M4 application by utilizing Picatinny rail-mounted devices. Consequently, there are now a multitude of sight/optical aid devices available; several of which mimic the original carrying handle with integrated sight style.

The most common and relatively economical solution to an Optic Ready firearm is the flip-up style sight. However, this design is rather impractical, as it often requires the use of a special tool, such as a hex driver, screwdriver, Torx® driver, etc. to mount, adjust or uninstall on the Picatinny rail. Furthermore, many of these devices are attached to the Picatinny rail by a single fastener, screw or bolt, and are consequently susceptible to loosening during use and the subsequent loss of sight calibration or zero; thus, creating the added burden of always having to carry a special tool for this purpose, which could prove to be especially burdensome in a tactical environment.

Moreover, the deviation of reliance upon Iron Sights to an electronic optical device, which can illuminate reticles, provide electronic magnification and/or thermal imaging, tends to produce an undesired dependence, thus effecting a considerable tactical disadvantage as these optics require a constant, replenishing source of power (i.e. batteries, power cells, etc.). However, once a source of power is no longer readily available, the device would be rendered inoperable, causing conditions to rapidly deteriorate.

Additionally, while many configurations of the flip-up type sight utilize a locking mechanism, which must be pressed or released to permit folding, they are typically not impact resistant once positioned into the flip-up orientation, making them susceptible to strike or impact damage.

Another problematic condition of prior art flip-up style sights is a deviation from the original MIL-SPEC sight centerline to the bore centerline. Because most rear flip-up style sights do not provide elevation adjustment or compensation, this condition can exceed the vertical adjustment travel (+/−) of the front sight post. As such, optics that are installed between flip-up sights can further compound this condition when original MIL-SPEC centerlines are not maintained.

Therefore, a need exists for a new and improved firearm sight system that an integrated flip-up rear sight for AR-15/10 and M16/M4 rifle variants. In this regard, the various embodiments of the present invention substantially fulfill at least some of these needs. In this respect, the firearm sight system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of providing an integrated flip-up rear sight for AR-15/10 and M16/M4 rifle variants.

SUMMARY OF THE INVENTION

The present invention provides an improved firearm sight system, and overcomes the above-mentioned disadvantages and drawbacks of the prior art. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide an improved firearm sight system that has all the advantages of the prior art mentioned above.

To attain this, the preferred embodiment of the present invention essentially comprises an elongated mounting rail including a plurality of transverse bars separated by intervening transverse mounting location channels extending from a rearmost channel to a forwardmost channel, the rail having an elongated upper surface, the rail defining a pocket below the upper surface and at least in part forward of the rearmost channel, and a sight arm pivotally connected to the rail and movable between an elevated position angularly offset from the upper surface of the rail and a stowed position in which the sight arm occupies the pocket. At least a forward portion of the sight arm may be entirely below the upper surface of the rail when in the stowed position. The entire sight arm may be entirely below the upper surface of the rail when in the stowed position. The sight arm may pivot on a pivot axis below the upper surface of the rail, and the pivot axis may be forward of the rearmost channel. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims attached.

DESCRIPTION OF THE CURRENT EMBODIMENT

An embodiment of the firearm sight system of the present invention is shown and generally designated by the reference numeral10.

FIGS. 1-3illustrate the improved firearm sight system10of the present invention. More particularly,FIG. 1shows the firearm sight system in use in the elevated position attached to a rifle12,FIGS. 2A & 2Bshow enlarged views of the firearm sight system in the elevated and stowed positions, andFIG. 3shows the firearm sight system in the stowed position. The rifle includes a frame/upper receiver14with a barrel16mounted to the front18of the upper receiver. The barrel defines a barrel axis20. A front sight22extends upward from a forward portion24of the barrel. The upper receiver has a top26that forms an elongated mounting rail28. The elongated mounting rail includes a plurality of transverse bars30separated by intervening transverse mounting location channels32extending from a rearmost channel34to a forwardmost channel36. The elongated mounting rail has an elongated upper surface38. The elongated mounting rail defines a pocket40below the upper surface and at least in part forward of the rearmost channel. A sight arm42is pivotally connected to the elongated mounting rail and is movable between an elevated position angularly offset from the upper surface of the elongated mounting rail and a stowed position in which the sight arm occupies the pocket.

As can be appreciated inFIGS. 2B & 3, at least a forward portion44of the sight arm42is entirely below the elongated upper surface38of the elongated mounting rail28when in the stowed position. In the current embodiment, the entire sight arm is entirely below the elongated upper surface of the elongated mounting rail when in the stowed position. The sight arm pivots on a pivot axis46located below the elongated upper surface of the elongated mounting rail. The pivot axis is located forward of the rearmost channel34. The elongated mounting rail has a rail width48defined between opposed left and right lateral rail edges50,52. In the current embodiment, the sight arm has an arm width54less than the rail width.

In the current embodiment, the entire sight arm42is forward of a rear end56of the elongated mounting rail28. The pocket40encompasses the left and right sight arm sides58,60and rear62when the sight arm is in the stowed position. The pocket defines a forward neck portion64having a first width and a rearward head portion66having a greater width. The sight arm defines a first sight aperture68and includes a pivoting aperture element70with a second smaller aperture72.

In the current embodiment, the pivoting aperture element70is movable between a first position in which the second smaller aperture72of the pivoting aperture element registers with the first sight aperture68to provide a reduce diameter sight, and a second position away from the first sight aperture. The sight arm42includes at least one magnet (upper and lower magnetic inserts74,76shown inFIG. 5) to movably secure the pivoting aperture element to the sight arm in at least one of the first and second positions. In the current embodiment, the first sight aperture defines a sight axis78when the sight arm is in the elevated position at least 2.5 inches above the barrel axis and preferably 2.6 inches above the barrel axis.

FIGS. 4 & 5illustrate the improved firearm sight system10of the present invention. More particularly, the firearm sight system is shown in exploded views so that all of its components can be appreciated. The sight arm42includes a rear sight post80, a screw lock pin82, and aperture pivot pin84, a rear sight base86, a traverse screw dust cover88, a traverse screw90, a base pivot pin92, a traverse lock detent ball94, a traverse lock spring96, a traverse guide pin98, pivoting aperture element70, and upper and lower magnetic inserts74,76. The rear sight base defines a screw aperture100that receives a threaded portion124of the traverse screw. The traverse screw also includes a knurled head portion126to facilitate rotation of the traverse screw. Traverse adjustment of the firearm sight system is performed by clockwise or counterclockwise rotation of the traverse screw, resulting in left or right movement of the rear sight post. The traverse screw's rotational setting is maintained by sixteen individual positional points158located on the underside of the knurled head portion around the screw axis160. The spring-loaded traverse lock detent ball assembled within the rear sight base engages the appropriate positional point on the traverse screw as the traverse screw is rotated during sight adjustment. The spring-loaded traverse lock detent ball also serves to provide constant spring pressure upon the traverse screw to ensure sight setting integrity upon strike or impact. Under spring protection, the knurled head portion of the traverse screw can be used to elevate the sight arm into the elevated position.

The base pivot pin92is received by a pin aperture102defined by the forward portion44of the rear sight base86of the sight arm42. The rear sight post80includes a right ear104and a left ear106. The right ear defines a pin aperture108, and the left ear defines a pin aperture110. The aperture pivot pin84is received by the pin apertures108,110. The pivoting aperture element70has a top112that defines a pin aperture114that also receives the aperture pivot pin. The rear sight base also defines a pin aperture162that receives the screw lock pin82. The upper magnetic insert74and the lower magnetic insert76each define a central bore116,118. The central bore116is axially registered with the first sight aperture68. The traverse screw dust cover88defines a central bore120and a detent aperture122located below the central bore. The central bore receives the threaded portion124of the traverse screw90, and the detent aperture is axially registered with the traverse lock detent ball94. The detent aperture enables the traverse lock detent ball to protrude through the traverse screw dust cover engage a selected individual positional point158located on the underside of the knurled head portion126of the traverse screw.

A rear spring block base128is releasably secured to the elongated mounting rail28on the upper receiver14by forward rear spring block pin130and rear spring block pin132. The forward and rear spring block pins are received by selected transverse mounting location channels32and by pin apertures142,144defined by the rear spring block base. The rear spring block base has a front150, rear152, and a transverse mounting location channel154defined by its top156. The rear of the rear spring block base defines a left bore146and a right bore148. The left bore receives a left rear spring block spring134and a left rear spring block detent ball138. The right bore receives a right rear spring block spring136and a right rear spring block detent ball140.

FIGS. 6A, 6B & 8illustrate the sight arm42. More particularly, the interaction between the pivoting aperture element70and the first sight aperture68is depicted. When the pivoting aperture element is in the lower short-range position depicted inFIG. 6Aand in the solid lines ofFIG. 8, the first sight aperture is unobstructed to provide a maximum diameter ghost ring, center-hold sight picture for short-range engagements at less than 300 m in accordance with MIL-SPEC standards. When the pivoting aperture element is in the upper long-range position depicted inFIG. 6Band in one set of the dashed lines ofFIG. 8, the first sight aperture is partially obstructed to provide a smaller diameter ghost ring, center-hold sight picture through the second smaller aperture72for long-range engagements at greater than 300 m in accordance with MIL-SPEC standards. The pivoting aperture element transitions between the upper and lower positions, as denoted by a second set of the dashed lines ofFIG. 8, by pivoting about pivot axis46defined by base pivot pin92. The pivoting aperture element is made of a suitable material that is attracted to upper and lower magnetic insert74,76so that the pivoting aperture element is releasably retained in both the upper and lower positions. Milled steps are provided on each side of the rear sight post to aid in overcoming the magnetic force exerted by the upper and lower magnetic inserts to lift the pivoting aperture element from either of the upper and lower positions.

FIG. 7illustrates the sight arm42. More particularly, the sight arm is shown in transition between the elevated and stowed positions. The forward portion44of the rear sight base86of the sight arm defines two recesses164,166. Folding and unfolding of the sight arm is guided and supported by the left and right spring-loaded rear spring block detent balls138,140located within the left and right bores146,148in the rear152of the rear spring block base128. The left and right rear spring block detent balls orientate and releasably lock the sight arm in the elevated position and releasably hold the sight arm down within the pocket40in the stowed position. Travel of the sight arm is inherently limited to 90° about the pivot 46 axis. Releasably securing the sight arm in the elevated position by the left and right rear spring block detent balls also serves to mitigate impact or strike upon the sight arm by simply folding the sight arm to prevent damage.

While a current embodiment of a firearm sight system has been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. Although AR15/10 and/or M16/M4 rifle platforms have been disclosed, the firearm sight system is also suitable for use with shotguns, light and medium machine guns, and other firearms. With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.