Gun-sight

Application filed June 29, 1918. Serial No. 242,516.

To all whom it may concern:

Be it known that I, Daniel Moreau Barringer, a citizen of the United States, and a resident of Haverford, in the county of Montgomery and State of Pennsylvania, have invented certain new and useful Improvements in Gun-Sights, whereof the following is a specification, reference being had to the accompanying drawings.

Although my invention may be said to relate primarily to sights for rifles or similar small arms, it is also applicable to machine guns and cannon, and it will, therefore, be understood that in using the expression “gun-sights,” I do not thereby intend to limit its use to any particular class or size of guns.

It will also be understood that the invention is adapted for use in connection with any desireci adjunctive appliances, such as elevating devices and the like, but to avoid complication I have not shown in the drawings, nor shall I describe in the specification, any of these concomitant features.

The features of novelty characteristic of my invention reside in the construction of the rear sight of the gun and can be employed in connection with any desired form of front sight.

Furthermore, the characteristic principles of the invention lend themselves to embodiment in structures comprising various developments of detail, and in order that the differentiation between several typical embodiments may be more readily appreciated, I have, in the accompanying drawings, represented a device embodying the main characteristics in progressive steps of detailed development.

Thus, Figure I, represents in perspective a gun-sight embodying my invention in a very simple form: Fig. I^a, being a view, in rear elevation, of the same embodiment.

Figs. II, III, and IV, are perspective views of sights embodying the invention with what may be considered as cumulative developments of details, Figs. II^a, III^a, and IV^a, being corresponding views, in rear elevation, of said respective embodiments.

In Figs. III^a, and IV^a, solid black is employed to indicate conventionally the body or main portion of the respective devices, in order to emphasize, by the stippled bands, certain detail features under conditions characteristic of the use of the sight at 55 night.

Fig. V, is an enlarged representation of the sight shown in Figs. II, and II^a, showing, in connection therewith, a preferred form of front sight, and so represented in 60 fore-shortened perspective as to indicate the preferred relation between the tip of the front sight and the optical center of the rear sight when shooting point-blank.

Fig. VI, is a similar view of the sight, ⁶⁵shown in Figs. IV, and IV^a, indicating in a conventional manner similar to that employed in Fig. IV^a, the appearance of both the front and rear sights when the device is used at night. 70

Referring to Figs. I, and I^a, 1, represents the main block, or body of the sight, which is provided with a dove-tailed base 2, adapted to engage in a corresponding seat in the gun barrel, or in an adjunctive device 75 mounted thereon. The rear face 3, of the sight (or that which is toward the observer), is inclined preferably at an angle of 45° to the horizon, such inclined face terminating, across its central region in a horizontal 80 straight edge 4, but being continued upward on each side in two similar vertical projections 5. 5, thus forming a flat bottomed notch accurately defined to the eye as rectangular and symmetrically transverse to 85 the axis of the gun-barrel, when properly viewed from the rear.

A straight groove is formed longitudinally along the center of the inclined face 3, and terminates accurately in the center of ⁹⁰the rear edge 4, of the notch, said groove being adapted to receive the strip 6, of material which is relatively bright, as compared with the dark surface of the metal of the body. For permanency, I prefer to make ⁹⁵this inlaid strip of ivory or some non-tarnishing metal, but paint, enamel or other adhesive material, contrasting in color with the main surface, might possibly be employed.

In Figs. II, and II^a, another embodiment is shown, the sight being similarly constructed with a body 21, dove-tail 22, rear inclined face 23, central notch 24, between the projections 25, 25, and inserted piece 26, 1θ5 of bright material, but with the additional feature that a deep groove 27, of semi-circular cross-section is formed longitudinally

1,363,553 along the center of the notch 24, from front to rear, the upper extremity of the bright piece 26, terminating accurately at the bottom of the groove, as indicated.

At the rear extremity, the outline of the edge of the groove 27, is semi-oval, by reason of the angle of intersection of the inclined rear face 23, as indicated at 28. When, however, the sight is viewed from the rear, in the position of use, as shown in Fig. II^a, the true semi-circular cross section of the groove 27, will be apparent.

Referring now to Figs. Ill, and III^a, a still further development of a typical device embodying the principle of the invention is shown. Save in one particular, about to be referred to, the structure of the sight shown in Figs. Ill, and III^a, is represented as identical with that shown in Figs. II, and II^a, the several parts being indicated by similar figures raised by 10. Thus, the body of the sight is 31, the dovetail 32, etc.

Here, as in the case shown in Fig. II, the bright strip 36, terminates accurately at the bottom of the semi-cylindrical groove 37, but I form in the inclined face of the sight, a semi-oval shallow groove 39, optically symmetrical xvith the outline of the rear extremity 38, of the groove 37, but with slight interspace, as shown. Said groove 39, is adapted to retain a band of material xvhich is luminous or visible in the dark. Such material, for instance a phosphorescent paint, can be rubbed into the groove, the surplus being completely wiped away so as to form a clearly defined luminous band, accurately surrounding, and optically corresponding xvith, the outline of the rear extremity 38, of the groove 37. The bright strip 36, in this instance bisects the luminous groove 39, and need not itself be luminous when the device is used at night. Under these conditions, the appearance of the rear face of the sight, when used in the dark, xvill be understood by reference to Fig. III^a, where the solid black portion indicates the general real- inclined face of the sight, the stippled portion 39, representing the luminous band, here shown as interrupted at the center of its bottom portion, by the non-luminous strip 36.

Referring now to Figs. IV and IV^a, a still further typical development is shoxvn, in which I have indicated all the structural parts of the sight, with the exception of the feature about to be mentioned, as substantially identical xvith those shown in Fig. Ill, the several parts being indicated by similar numerals again raised by 10. Thus, the main body is marked 41, the dove-tail 42, etc. In this instance, however, I provide two longitudinal grooves 40, which extend preferably along the entire inclined surface 43, near its edges, terminating in accurate central relation to the two uprights 45. Said grooves 40, are adapted to be filled with material luminous in the dark, in the same manner as is the groove 49, which surrounds the rear extremity of the groove 47, 70 so that, in the dark, the rear of the sight xvill present the appearance indicated conventionally in Fig. IV^a, xvhere the stippled lines 40, are shoxvn foreshortened and disposed with mathematical accuracy on each 7 5 side of the central notch 47, and luminous band 49.

Referring now to Fig. V, I have therein shown a preferred form of front sight, in what I consider the most satisfactory ele- 80 vation relatively to a rear sight, of the character shown in Fig. II. Said front sight comprises a vertical stem 50, surmounted by a bead 51, and? as the result of experience I consider it desirable (though, of course, not 85 essential), that when the observer is aiming point-blank at a given object, the top portion of the periphery 51, should be tangential to the line which the rear edge of the notch 14, presents to the eye. 90

In Fig. VI, I have represented conventionally a preferred embodiment of front sight to be used in connection xvith the form of rear sight shoxvn in Figs. IV. and IV^a, in this instance I consider it desirable that 9 5 the stem 60, of the front sight should not be luminous at night, and hence have indicated it by dotted lines, but the tip or bead 61, should have its rear face covered with a luminous material, such as phosphorescent 100 paint, and for the best results, the upper surface of the periphery of the bead 61, should be tangential to the transverse edge line of the notch 34.

Having described these several typical 105 embodiments of my invention, I will now proceed to describe what may be termed theoptical characteristics due to the structural arrangement of the parts which embody the new and improved features. no

A primary and important feature consists in the fact that an elongated sloping surface rising at an angle of approximately 45°, to the horizontal is presented to the eye instead of a vertical surface, as in most rear 115 sights. The result is that if an optically bright line extends along the exact longitudinal center of this surface, the eye xvill catch this line near its base and follovc it up to the bottom of the notch in the upper 120 portion of the sight, without conscious effort. To illustrate the matter by familiar examples, the eye xvill catch and follow a straight road extending up an evenly inclined hill from its lowest to its highest 125 point, much more readily, and, so to speak, automatically, than it would follow a x^rertical chimney or tower from its loxvest to its highest point. I beliex^re that this phenomenon .is .due to what may be considered as a 130

1,363,553 S part of the general principles, upon which the so-called laws of perspective depend, but this statement, however, is simply by way of explanation and is not intended to be restrictive. Whatever the true explanation, however, the specific effect here referred to is substantially absent if the angle of inclination of the rear face of the sight is greatly below 45°.

Another desirable feature is that by the use of this optically bright line, in perspective , I may employ a relatively wide or open notch, with the effect that the user of the sight may readily see all around the object or point at which he is aiming. Of course this advantage of the bright band in connection with the wide notch is most perfectly realized when the notch is wide as compared with the front sight employed,—or, in otherwords, get a general view of portions of his objective adjacent the point aimed at.

While this feature of a wide notch is not in itself new, its value is greatly enhanced when employed in connection with the inclined rear surface and bright central line thereon. This line produces its effect of causing the eye to locate the front sight in the center of the notch most perfectly when the line is, relatively, quite narrow in comparison with the notch,—irrespective of the relative width of notch and front sight. It may be added that the peculiar value of the combination above described is more notable when the observer is obliged to aim quickly at a moving object, the conditions being quite different from those which exist when aiming at an ordinary stationary target.

All these points are true of the simplest type of my inproved sight shown in Figs. I, and I^a, but with the progressive development of details indicated in the remaining figures, still greater accuracy of aim may be obtained almost unconsciously on the part of the observer, by reason of the optical characteristics afforded by the parts. Thus, in the arrangement shown in Fig. II, the bright line 26, terminates accurately at the bottom of the central groove 27, and the eye is not only additionally guided by the two uprights 25, on either side of the wide notch, but also the closer definition afforded by the rear edge of the semi-circular groove 27, to which the inclined bright strip 26, directly leads.

Referring now to the types of the invention shown in Figs. Ill, III^a, and IV, IV^a, the usefulness of the device is enhanced when the device is used in the dark, the eye being guided by the luminous band symmetrically arranged with relation to the fine of profile, and, as shown in F?g. VI, the tip or bead of the front sight, being also luminous on its rear face, can readily be found by the observer and located centrally with relation to the straight bauds

40, and to the optical center of the curved band 49, which surrounds the rear face of the groove 47, the eye being aided by the interruption of the luminous band 49, at the center of its lowest portions. 70