US3688408A

US3688408A - Range and elevation determining device

Info

Publication number: US3688408A
Application number: US116843A
Authority: US
Inventors: James P Smith; Erwin Michelson
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-02-19
Filing date: 1971-02-19
Publication date: 1972-09-05
Anticipated expiration: 1989-09-05

Abstract

A range and elevation determining device serving in one form as a sight for direct fire gunnery. May be in the form of a stadimetric ranging and sight setting device that when adjusted by the gunner to frame a target automatically will dictate proper elevation of the gun muzzle to accommodate known trajectory and range characteristics of certain ammunition and will direct, upon firing the gun, the projectile thereof to a selected kill point on the target. A front sight is provided as a rotatable disk that is pivotally mounted on an upright support on the gun muzzle. It may be a ''''see-through'''' or transparent disk. This disk is provided about its axis with a spiraled framing area having curved marginal framing stadia or lines that gradually converge in the direction of disk rotation from point blank or near range toward the longest effective range of the gun on which it is mounted and the ammunition used therein. Framing of the height of the image of a distant target between these marginal stadia automatically will indicate range whether or not such data is readably provided on the device. Preferably the disk is provided with annularly spaced radial lines that are respectively identified by readable range markings. The spiraled framing area may be a slot in the disk. The disk may be a reticule that is rotatably mounted in image planes of optical instruments, such as binoculars, gunner''s telescopes and periscopes, and provided with suitable readable markings that inform one accurately of the range and elevation data.

Description

United States Patent Smith et a1.

[ Sept. 5, 1972 [54] RANGE AND ELEVATION DETERMINING DEVICE [72] Inventors: James P. Smith, 71 Vanderwater Ave., Floral Park, NY. 11001; Erwin Michelson, 1.02 Eighteenth Ave., East Paterson, NJ. 07407 [22] Filed: Feb. 19, 1971 [21] Appl. No.: 116,843

52 US. Cl ..33/64 B, 33/1 SP, 33/54 51 Int. Cl. ..G0lc 3/00 [58] Field of Search ...33/64 B, 64 R, 64 c, 71, 49 R,

33/49 c, 1 SP, 54

I56] References Cited UNITED STATES PATENTS 444,406 1/1891 Andrews et al ..33/64 B X 1,466,913 9/ 1923 Matthews ..33/54 3,365,800 1/1968 Carella ..33/64 R X FOREIGN PATENTS OR APPLICATIONS 630,706 12/1961 Italy ..33/64 B 79,570 2/1934 Sweden ..33/64 B 105,637 10/1942 Sweden ..33/ 1 SP Primary Examiner-Robert B. Hull Att0meyl-larry M. Saragovitz, Edward J. Kelly and Herbert Berl [57] ABSTRACT A range and elevation determining device serving in one form as a sight for direct fire gunnery. May be in the form of a stadimetric ranging and sight setting device that when adjusted by the gunner to frame a target automatically will dictate proper elevation of the gun muzzle to accommodate known trajectory and range characteristics of certain ammunition and will direct, upon firing the gun, the projectile thereof to a selected kill point on the target. A front sight is provided as a rotatable disk that is pivotally mounted on an upright support on the gun muzzle. It may be a see-through or transparent disk. This disk is provided about its axis with a spiraled framing area having curved marginal framing stadia or lines that gradually converge in the direction of disk rotation from point blank or near range toward the longest effective range of the gun on which it is mounted and the ammunition used therein. Framing of the height of the image of a distant target between these marginal stadia automatically will indicate range whether or not such data is readably provided on the device. Preferably the disk is provided with annularly spaced radial lithes that are respectively identified by readable range markings. The spiraled framing area may be a slot in the disk. The disk may be a reticule that is rotatably mounted in image planes of optical instruments, such as binoculars, gunners telescopes and periscopes, and provided with suitable readable markings that inform one accurately of the range and elevation data.

8 Claims, 7 Drawing Ih'gures PATENTED 5|973 I 3.688.408

- sum 1 OF 2 8 8 N N mm i 9 INVENTORS, JAMES E SMITH, BY; ERWIN MICHELSON W M ,qrroRNEY PATENTEDSEP 51912 SHEET 2 BF 2 INVENTORS JAMES PSMITH BY- ERWIN MICHELSON A M W1 1 RANGE AND ELEVATION DETERMINING DEVICE BACKGROUND OF THE INVENTION The present invention relates to range and elevation determining devices that are particularly useful in gun nery, such as of the direct fire category, e.g., shoulder fired weapons of the LAW (light anti-tank weapon) type. For this purpose it may be embodied in the front sight assembly of the weapon.

Prior to the present invention it has been proposed that the sighting equipment of such a weapon embody means which will present to the gunner in the line of sight an image of the distant target. The size of the image of the distant target object bears a certain geometrical relation -to the range or distance between the point of observation and the object, i.e., the angle subtended by any particular dimension of the distant object depends upon this dimension and such distance. Some types of such guns have no range finding or stadimetric devices as such, and require range estimation by the gunners usually under very difficult conditions. Others provide in the front sight assembly vertical stadia lines to facilitate range estimation with calibration thereof related to target object side-on or head-on view. In the latter cases when the target object is viewed from any other angle range estimation errors readily are made since the observer must estimate such angle.

It has also been proposed in the Walker et al. British Pat. No. 1204 of Jan. 26, l888 that a small weapon or shoulder-fired rifle be equipped with complicated sighting equipment that employs a sophisticated telescope as a rear sight. Use of this telescopic rear sight employs a knowledge of the average height of a recognizable target object for determining range and translating this value into the action of the equipment for attaining a hit with some accuracy. It also permits embodiment thereof in range finding devices, such as telescopes and binoculars. In any case it requires installation in such objective system of two vertically movable masking plates having opposed, horizontal and parallel edges between which a lateral viewing slot is defined, with these plates being simultaneously movable relative to each other in their plane of alignment for varying the width of the viewing slot with the opposed slot-defining edges continuously located at equal distances below and above the axis of the lens system.

In the rifle supported form of the Walker et al. device the telescope is mounted upon a parallel linkage so that it may be raised and lowered by hand while keeping its objective axis aligned with the front sight to define a line of sight to the distant target. The telescope tube slidably carries a surrounding sleeve. Internally of the tube this sleeve carries by vertically aligned compound screw and slidable pin a stirrup collar through which an opposed pair of vertically spaced, longitudinally extending spring leaves extend. Forward ends of these spring leaves are fixed to top and bottom portions of the tube with their rear ends bent inwardly toward each other to form the opposed and slot-defining masking plates. The stirrup supporting screw and pin extend out through longitudinal slots in the top and bottom portions of the tube, to permit longitudinal adjustment of this sleeve and stirrupassembly along the telescope tube, with bell cranks on some lever arms of the parallel linkage sliding this assembly along the tube axis by connecting links as the telescope is raised and lowered. This longitudinal adjustment of the stirrup imposes a camming action upon the spring leaves to cause the opposed horizontaledges of the masking plates to approach each other and, alternatively, to separate for adjustable framing of the image of the distant target.

One of these bell crank carrying arms has its mounting axle equipped with a pointer which swings along. a graduated scale or quadrant so as to indicate the range as the opposed plate edges frame the bottom and to of the image of the distant target.

In the binocular embodiment of the Walker'et al. device each of the pair of sight tubes is equipped with the opposed pair spring leaves and their encompassing stirrup. The compound screw of this assembly, which in this form is at a fixed point on the sight tube translates the stirrup transversely or across the tube optical axis to move one of the spring leaves therewith while the inner end of the screw bears against the opposed spring leaf to move it relative to the first in the opposite direction. Gearing is employed to gang these compound screws together and one or more of the gears carries a graduated range scale.

proposals are solved in a simple and economical manner by the present invention.

SUMMARY Various embodiments of the present range and elevation determining device, which may serve as a front sight for direct fire gunnery or as a reticule in op tical field instruments, e.g., binoculars, gunners telescopes and periscopes, to provide accurate range data, employ a simple rotatable disk and support therefor. This disk is provided with a spiraled seethrough framing area defined between curved marginal framing stadia that gradually converge in the intended direction of disk rotation for closely framing visually therebetween the image height of a distant object. This framing area at its greatest width is located most closely to the axis of rotation of the disk and spirals gradually outward toward the periphery of the latter as its marginal stadia progressively converge. As a result, when the height of the object image is closely framed between these marginal stadia by suitable rotary adjustment of the disk the angular or radial location of this framed image in the disk framing area indicates the range between the location of the object and the point of observation while the radial distance from the axis of the disk to a selected or intended hit portion of or point of impact on the framed image indicates the angular elevationnecessary to accommodate the characteristic trajectory of a certain projectile. In a preferred embodiment radii of the disk are delineated thereon as representative of certain range distances for indicating at least some of the radial locations at which such ob ject image framing is to be effected and, if desired, the disk face may hear an annular graduation of radials to enhance its use as a range finder.

The spiraled framing area of this disk may be in the form of a spiraled slot with the curved edges thereof constituting its marginal stadia. In such form the disk may be constructed of opaque sheet material. In a preferred form the disk is constructed of see-through transparent plastic sheeting with the spiraled framing area defined thereon by embossed or scribed curved lines to constitute the marginal framing stadia. This preferred form of the disk permits the scribing thereon, between the marginal framing stadia of a curved medial line that extends through points at the range distances radii which will indicate a these range distances the desired points of impact for the intended target. This medial line defines the hit point at each of all of the range distances between the initial and terminal points of this spiraled framing area and with the radial distance between this hit point line and the axis of the disk indicating the required angular elevation of the weapon tube relative to the line of sight.

When this range and elevation determining rotary disk is employed as a front weapon sight its exposed circumferential rim may serve for ready engagement by the gunners hand for simple rotation thereof about its axis to obtain the desired adjustment for the close framing of the target image height in the curved framing area.

When such a rotary range and elevation determining disk is laid out and produced for use as the front sight of a particular weapon, in relation to the distance between this front sight and the rear sight and with respect to characteristics of certain particular ammunition to be used in this weapon for accurate accommodation of the trajectory and effective range thereof, duplicates thereof for simple mounting upon the numerous reproductions of the weapon may be economically and rapidly produced by simple die-cutting, and stamping procedures. The mounting thereof can also be effected in a simple and rapid manner.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects of the invention will in part be obvious and will in part appear from reference to the following detailed description taken in connection with the accompanying drawings, wherein certain relative dimensions have been exaggerated for clarity of understanding, with the understanding that dimensions of exemplary gun parts are so small relative to range distances that in showings involving both the former virtually disappear or may be ignored to avoid confusion in such small scale depictions. In these drawings like indicia and numerals identify similar parts throughout, wherein:

FIG. 1 is a perspective view of a light anti-tank weapon LAW-bazooka) in which a form of the present range and elevation determining device may be embodied to advantage as a front sight, the telescopic gun tube thereof being shown in extended condition with the rear and front sights being swung up to operative upright positions;

FIG. 2 is a rear elevational view, to enlarged scale, of the rear sight of the weapon depicted in FIG. 1, with the protective hood thereof removed;

FIG. 3 is a rear elevational view, to enlarged scale, of the front sight of the weapon depicted in FIG. 1;

FIG. 4 is a rear elevational view, to larger scale, of a front sight assembly which may be advantageously substituted for that of FIG. 3;

FIG. 5 is a diagrammatic layout to greatly reduced scale of the combination of rear and front sights of FIGS. 2 and 4 when mounted upon the weapon of FIG. 1, illustrating geometric relationships of range and trajectory for certain ammunition to be fired through the gun tube ofFIG.1;

FIG. 6 is an enlarged diagrammatic view of the FIG. 1 weapon when equipped with the rear sight of FIG. 2 and the front sight of FIG. 4, that illustrates the necessary angular elevation of the gun tube for attaining a hit at a certain intermediate range; and

FIG. 7 is a diagrammatic view similar to FIG. 6 illustrating a greater angular elevation required to attain a hit at a greater range which may be in the vicinity of the greatest reliable range of which this weapon is capable.

The weapon 10 of FIG. 1, which is illustrated by way of example as an LAW that may be improved to advantage by the present invention, includes a gun tube 11 formed of telescopic rear and

front sections

12 and 13 which are shown in their relative extended positions, readied for receiving ammunition therein and firing projectiles therefrom. The gun tube 11 conventionally includes triggering mechanism 14 operated by a lanyard 15 from a trigger 16, with the latter carried in a medial position by a support 17 upon which is pivotally mounted the rear sight (RS). The rear sight (RS) is shown swung up to its upright position for use. The front end or muzzle 18 pivotally supports by a bracket 19 the front sight (FS) which has also been swung up to its upright position of use.

As will be understood from FIG. 2 the fulcrumed rear sight (RS) includes a pivotally supported bracket 20. This bracket 20 conventionally has a temperature adjusting slide 21 equipped with a cold temperature sight peephole RSC) and a normal temperature peephole( RSN).

As will be understood from FIG. 3 the fulcrumed front sight (FS) includes a see-through or transparent plastic card 22 which is embossed or scribed with a vertical center line 23 across which extend vertically spaced, transverse stadia 24, with some of the latter identified by embossed or scribed range meter indicia or markings. The vertical center line 23 is flanked on opposite sides by opposed, upwardly extending, curved stadia 25 and between which a target image may be framed for estimating the range distance of the target from the weapon or, more particularly, the rear peep sight (RS). In FIG. 3 is illustrated at 26 a framing between the stadia lines 25 and 125 of a side-on view of the objective image of a tank, and such framing provides the gunner with information to aid him in estimating the range distance to the tank which is afforded by the basic stadirnetric principle that the angle subtended by an object depends on its length or width and its distance from the observer. Such a front sight (FS), which includes the upright card 22, may be employed also for framing a head-on view of the tank by known technique, but such front sight equipment readily permits range error to be made by the observer or gunner when the target tank is viewed from any other angle, since such angle must be estimated. The front sight card 22 also conventionally flanks opposite sides of the vertical center line 23 with lead markings (shown as plus signs which may also be employed in the improved front sight of the present invention.

For the purpose of understanding the FIG. 4 embodiment of the present invention as a front sight of such a FIG. 1 gun, which will be described hereinafter in detail, it should be recalled that intelligence and experience has provided the information that most enemy tanks now are about feet (10') from the ground to the top of the turret, and intelligence information will have apprised the gunners of recognizable characteristics of such tanks so that they will instantly associate the observed type with such a characteristic height. For the purpose of the following exemplary description of the present invention it will be assumed that such target tank will have a height of about 10 feet (120 inch or 3.048 m). By using the target height rather than the target length or width the source of prior range estimation error is eliminated automatically.

In the front sight FIG. 4 embodiment the plastic card 22 has substituted therefor an upright support strip 30, which may be of see-through or transparent plastic or, if of opaque material, such as sheet metal, may be provided with a suitable window 31 below a pivot point or axis 32. At the axis point 32 a suitable pivot pin, which may be a rivet or other simple type of fastener axle, rotatably supports a see-through or transparent plastic disk 33, which is preferably of relatively stiff sheeting, mm be rotated by hand, and equipped, if desired, with a knurled circumferential edge, such as that which is indicated at 34, and it is to be understood that other suitable means, such as simple mechanism which will readily occur to one skilled in the art, may be provided for effecting such rotation of this disk. The disk 33 is scribed with a plurality of equally-spaced radials, such as (RR-l,-RR-2, RR-3,,RR4, and RR-S which may delineate ranges in meters of 100m, 200m, 300m, 400m, 500m. Such radials may be identified on the disk by suitable markings readily to inform the observer of such ranges and it will be understood that additional radials may subdivide the intervening sectors, or the disk may carry in the latter graduations, for more accurate information as to range and also to permit such a rotary disk to be used as a range finder if desired. Such a disk will be particularly designed for .each type of weapon on which it is to be mounted as the front sight thereof with respect to the particular ammunition that has been standardized for use therein.

The bracket strip also has its rear face provided with a suitable guidance marker or pointer, such as a scribed vertical line (VH), and initially in designing the disk 33 for use on a particular weapon, such as an LAW having an effective range of about five hundred (500 meters with the ammunition specially designed for use therein, the pivotally mounted disk will be rotated to align its one hundred (100 meter radial (RR-l) with the pointer line (VH). The weapon will then be raised to the firing position on a testrange of known characteristics and under such conditions that the line of sight through the (RS) peephole and a lower sector of the (FS) disk 33 is level. This will determine the location of a point (KP-l) to be marked on the radial (RR-l) which represents the kill or hit point, i.e., the point of ing radials (RR-2, RR-3, RR-4, and RR-S) to define thereon the series of successive points (KP-1, KP-Z, KP-3, KP-4, and KP-S), with the same target being located respectively at the proper ranges for each of these radials. These hit points will thus have defined on the rear face of this disk a series thereof which spirals gradually outward toward the periphery of the latter and they will guide the scribing thereon of a spiraling curved line (AEL-angular elevation line) which will indicate at these range distances and intermediate range distances the desired point of impact on the intended target at such ranges.

The rear face of this front sight disk 33 will then be provided with suitable curved spiraling marginal lines for framing the height of the images of the target at the various ranges. These marginal stadia (FSB-framing stadia bottom) and (FST-framing stadia top) are scribed on the rear face of the front sight disk 33 in accordance with a determination of the width of such framing area at the various ranges, and this spacing (Ws may be determined at any particular range by the following equation:

(Ws= Bh/R), in which Ws is spacing between marginal lines for framing the object height at the top and bottom of target mock-up; B is distance from front sight to rear sight;

h is height of target; and R is distance to target from rear sight.

By way of example, it may be assumed that a target mock-up for the purpose of this equation and the laying out on the sight disk 33 of the spiraling marginal stadia (PS8) and (FST) may have a height (h) of ten feet (120 inch or 3.048m). Assuming that the distance (B) from the rear sight peephole (RS) and the front sight (FS) is one-half meter (0.5m or 19.7 inch) the spacing (Ws) between the marginal stadia (FSB) and (FST) at the various range radials (RR) is computed in the following manner;

These calculations may be tabulated as follows:

Range m It will thus be seen that the spiraled area defined between the marginal stadia (F88) and (FST) gradually recedes from the central disk axis 32 toward the periphery of the disk with these stadia gradually converging, so that the radial distance from the disk axis to a selected portion, such as the desired point of impact, of the target image that is framed in this area is indicated by the curved medial line (AEL) as the angular elevation necessary to accommodate the characteristic trajectory of a certain projectile at the target range which is indicated by the length of the radial of this disk to such impact point. Since the angular location on the disk 33 of any particular radius thereof (marked or not thereon) identifies a certain range between the point of observation and the location of the distant object, the close framing of an image of the latter between the marginal stadia (FSB) and (PST) at a point of reference, such as the vertical hairline (VH) of FIG. 4, so that the radius which is aligned with the latter extends approximately through the center of such image, this angular position of the disk or location of this radius can be read as the range. At this same time the radial distance along this disk radius between the disk axis and the approximate center of the distant object, such as where this radius crosses the angular elevation line (AEL) that will constitute the kill point or point of impact (KP), indicates the angular elevation necessary to accommodate the characteristic trajectory of a certain projectile.

In the FIG. diagrammatic view is indicated the sighting system of the gun of FIG. 1, employing the rear sight (RS) of FIG. 2 and the front sight (FS) of FIG. 4, with a target (X) located at a range distance (R-2), of 200m) from the point of observation or the location of the rear sight and, alternatively, located at'a range distance (R-5) of (500m) from that point of observation. It will be seen that the height (h) of the target at (X-2) subtends a relatively wide angle which, at the vertical plane of the front sight (FS), is also subtended by the framing area width (Ws-2). It will also be seen that the height (h) of the target at (X-S) subtends a relatively smaller angle which at the vertical plane of the front sight (FS) is also subtended by the relatively smaller framing area width Ws-5).

It will be noted from FIG. 5 that the trajectory (Th-2) of the relatively flat trajectory path (TP-2) at the range (200m) requires a relatively small angular elevation of the axis of the gun tube 1 l in order that the projectile shall hit the target (X-Z) at the kill point (KP-2). This is more graphically illustrated in FIG. 6 wherein-the relatively small angle of elevation is indicated at (01-2). It will further be seen that the trajectory Th-S) of the more highly arched trajectory path (TP-S) requires a relatively larger angular elevation of the axis of the gun tube 11 in order that the projectile shall hit the target (X-S) at the kill point (KP-5). This latter is more graphically illustrated in FIG. 7'wherein the relatively larger angle of elevation is indicated at (a-S). a a.

It is to be understood that while it is preferred to form the rotary disk 33 from see-through or transous that in producing such a range and elevation determining device in the manner indicated it may be prepared for variously differing types of targets each having its own average or standardized height, so that a weapon equipped therewith may be accurately used against differing targets, e.g., pillboxes, troops, fortifications, and other types of vehicles. Such a range and elevation determining disk may also be utilized as a reticule in optical instruments, such as binouculars, gunners telescopes and periscopes, to provide accurate range and elevation data for use by gunners. For

the latter purpose the rear face of the disk may bear' readable graduated scales with one arranged in an annular zone of the disk to indicate range and one or more others provided radially thereof to indicate angu lar elevation.

The designation herein of a range and elevation determining device is not used in a sense to imply that the device itself must bear indicia or markings which permit direct reading of such values. In certain forms of these devices which embody the features of the invention the shapes and sizes of structural parts, when produced or assembled in accordance with the teachings herein, either automatically impose such values upon the desired and attained end result without requiring a direct reading thereof or give information from which such values may be translated, if desired.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having described our invention, what we claim as new and desire to secure by Letters Patent is the novel subjects matter defined in the following claims.

We claim:

1. A range and elevation determining device comprising a rotatably mountable disk provided with a spiraled see-through framing area defined between curved marginal framing stadia that gradually converge in the intended direction of disk rotation for closely framing visually therebetween the image height of a distant object, said framing area at its greatest width being located most closely to the axis of rotation of said disk and spiraling gradually outward toward the .periphery of the latter as its marginal stadia progressively converge whereby upon closely framing such object image height between said stadia at any particular radial location the latter and the radial distance from the axis of said disk to a selectedportion of the framed parent plastic sheet it may be formed of opaque sheetto form a spiraled slot with the curved edges thereof constituting its marginal stadia. Also, it should be obviindicating at least some of the radial locations at which i such object image framing is to be effected.

3. The range and elevation determining device of claim 1 in which the spiraled framing area is in the form of a spiraled slot with the curved edges thereof constituting its marginal stadia.

4. The range and elevation determining device of claim I in which said disk is in the form of a seethrough sheet with the spiraled framing area defined thereon by curved lines to constitute the marginal framing stadia.

5. The range and elevation determining device of claim 4 in which the spiraled framing area is provided with a longitudinally extending, curved medial line scribed through desired points of impact at various ranges for a certain type of object that is to be an intended target.

6. The range and elevation determining device of claim 2 in which said disk is rotatably mounted in an upright plane on the muzzle of a projectile shooting in which (Ws) is the spacing between the curved marginal stadia for framing the height of an image of a particular known object as the intended target, (b) is the distance nths s f ta PWEQLQ Q), is 19 10 probable height of the target object and (R) is the range distance between the rear sight and the target object.

7. The frontweapon sight of claim 6 in which said disk is in the form of a see-through sheet with the spiraled framing area defined thereon by curved lines to constitute the marginal framing stadia between which is scribed a curved medial line extending through points at the range distances radii which indicate at these range distances the predetermined point of vulnerability of the intended target with this medial line defining the hit point at each of all the range distances between the initial and terminal points of this curved framing area and with the radial distance between this hit point line and the axis of said disk indicating the angular elevation of the weapon tube relative to the line of sight.

8. The front weapon sight of claim 7 in which the circumferential rim of said disk is exposed for engagement by a gunners hand for rotation thereof about its axis to attain close framing of the target image height in the curved framing area by the marginal stadia of the latter at the actual range distance.

Claims

1. A range and elevation determining device comprising a rotatably mountable disk provided with a spiraled see-through framing area defined between curved marginal framing stadia that gradually converge in the intended direction of disk rotation for closely framing visually therebetween the image height of a distant object, said framing area at its greatest width being located most closely to the axis of rotation of said disk and spiraling gradually outward toward the periphery of the latter as its marginal stadia progressively converge whereby upon closely framing such object image height between said stadia at any particular radial location the latter and the radial distance from the axis of said disk to a selected portion of the framed image indicates the range between the location of the object and that of observation and the angular elevation necessary to accommodate the characteristic trajectory of a certain projectile.

2. The range and elevation determining device of claim 1 in which radii of said disk are delineated thereon as representative of certain range distances for indicating at least some of the radial locations at which such object image framing is to be effected.

4. The range and elevation determining device of claim 1 in which said disk is in the form of a see-through sheet with the spiraled framing area defined thereon by curved lines to constitute the marginal framing stadia.

6. The range and elevation determining device of claim 2 in which said disk is rotatably mounted in an upright plane on the muzzle of a projectile shooting weapon as its front sight and which is observable through a rear sight of the latter, the transverse width (Ws) of the spiraled framing area at any point along the latter being determinable be the formula (Ws Bh/R), in which (Ws) is the spacing between the curved marginal stadia for framing the height of an image of a particular known object as the intended target, (b) is the distance between these front and rear sights, (h) is the probable height of the target object and (R) is the range distance between the rear sight and the target object.

7. The front weapon sight of claim 6 in which said disk is in the form of a see-through sheet with the spiraled framing area defined thereon by curved lines to constitute the marginal framing stadia between which is scribed a curved medial line extending through points at the range distances radii which indicate at these range distances the predetermined point of vulnerability of the intended target with this medial line defining the hit point at each of all the range distances between the initial and terminal points of this curved framing area and with the radial distance between this hit point line and the axis of said disk indicating the angular elevation of the weapon tube relative to the line of sight.

8. The front weapon sight of claim 7 in which the circumferential rim of said disk is exposed for engagement by a gunner''s hand for rotation thereof about its axis to attain close framing of the target image height in the curved framing area by the marginal stadia of the latter at the actual range distance.