Polymer marking projectile with integrated metallic sealing ring

DESCRIPTION

Polymeric marking projectile with integrated metal sealing ring.

TECHNICAL FIELD

The technical field generally refers to training projectiles used in connection with bore rifled weapons, and more particularly refers to non-lethal polymeric marking projectiles.

BACKGROUND

US 5,035,183 A, US 2011/048270 A1 and US 5,277,460 A constitute relevant prior art documents. Low-energy, non-lethal marking projectiles are often used in conjunction with small-bore rifled weapons (eg, pistols, rifles, submachine guns, and the like) to provide a realistic training experience. Such projectiles typically include a forward-most polymeric shell portion that encloses a semi-viscous color marking compound and a rear base portion that mates with the shell portion. The fit between the housing and the base is typically provided through a push fit or press fit. The carcass portion is configured so that, during impact, the marking compound is expelled from the carcass in a controlled manner, typically along predefined break lines.

Known polymeric marking projectiles can be unsatisfactory in several respects. For example, suboptimal storage of such projectiles, particularly projectiles using water-based marking compounds, can cause significant moisture evaporation across the shell / base interface and consequently a reduction in viscosity and viscosity. mass of the marking compound. This aging effect, which is exacerbated by high temperature and humidity conditions, is due in part to the difficulty of achieving a tight seal between polymeric components, which are notoriously subject to high dimensional tolerances and various assembly restrictions.

Premature aging in the form of moisture loss and marking compound phase change can result in decreased marking effect and / or non-uniform mass distribution, which in turn can lead to reduced stability. gyroscopic in the muzzle of the weapon. Furthermore, within any particular batch of marking projectiles, the moisture loss can vary widely between individual projectiles. This results in a greater variation in the initial velocity of the projectile and a greater dispersion of the impact.

Accordingly, it is desirable to provide improved polymeric marking projectiles with improved service life and flight stability. Other desirable elements and features of the present invention will be apparent from the following detailed description and appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.

RESUME

A marking projectile according to one embodiment is configured to be fired through the barrel of a firearm having a rifling formed therein. The marking projectile includes a polymeric base portion configured to engage with the rifling of the barrel and a polymeric forward housing portion coupled to the base portion. The polymeric front shell portion has a cavity formed therein to accommodate a marker compound and a structure configured to deform on impact and thereby release the marker compound. The marking projectile also includes a metallic annular sealing component configured to seal the polymeric front housing part to the polymeric base part.

According to one embodiment, there is provided a method of forming a marking projectile configured to be fired through the barrel of a firearm having a rifling formed therein. The method includes: forming a polymeric base portion configured to match the rifling of the barrel; forming a polymeric front shell portion having a cavity formed therein and having a structure configured to deform on impact to expose the cavity; inserting a marking compound into the cavity; coupling the polymeric base part to the polymeric front shell part; and sealing the polymeric front shell part to the polymeric base part with a metal annular sealing component.

According to one embodiment, a marking projectile is configured to be fired through the barrel of a firearm that has a rifling formed therein. The marking projectile includes a polymeric base portion configured to engage with the rifling of the barrel, and a polymeric forward casing portion coupled to the base portion so that the base portion and the forward casing portion partially overlap axially. The polymeric front housing portion has a cavity formed therein to accommodate a

ES 2 744 550 T3 marker compound and a structure configured to deform on impact and thus release the marker compound. The marking projectile also includes a crimped metal ring configured to seal the polymeric front housing portion to the polymeric base portion by applying a radial compressive force thereto. The crimped metal ring has a non-crimped portion molded in conjunction with the polymeric base portion, and a crimped portion that applies radial compression to the outer surface of the polymeric front shell portion.

DESCRIPTION OF THE DRAWINGS

Exemplary embodiments will be described hereinafter in conjunction with the following drawing figures, in which like numbers denote like elements, and in which:

Figure 1 is an isometric overview of a marking projectile in accordance with one embodiment.

Figure 2 is a side view of the marking projectile of Figure 1.

Figure 3 is a cross-sectional view corresponding to the side view of the marking projectile shown in Figure 2.

Figure 4 is a detailed cross-sectional view of a crimp region '4' of Figure 3.

Figure 5 is an exploded view of a marking projectile in accordance with one embodiment.

Figures 6-8 depict the progressive deformation of an exemplary marking projectile during impact.

Figure 9 illustrates a marking pattern resulting from impact in accordance with one embodiment.

DETAILED DESCRIPTION

In general, the subject described herein refers to an improved non-lethal polymeric marking projectile incorporating a metallic annular seal (for example, through a crimp ring) that significantly improves service life while at the same time increasing the stability of the projectile. In that regard, the following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any express or implied theory presented in the above technical field, background, brief summary, or the following detailed description. It will be understood that the drawing figures are not necessarily drawn to scale and may be referred to herein, without loss of generality, as isometric (as opposed to perspective) drawings even when such drawings are not strictly isometric, but are, rather, axonometric as is known in the art. The nature and operation of conventional firearms and ammunition, in particular bore rifled firearms, are well known and need not be described in detail herein.

Referring now to the isometric exterior view of Figure 1, a marking projectile 100 according to one embodiment generally includes a polymeric base part (or simply base part) 101, a polymeric front shell part (or simply a housing) 102, and an annular metal sealing component (or simply sealing component) 103 configured to seal the housing part 102 to the base part 101 (for example, by crimping a suitably malleable metal ring). Base portion 101 is configured to engage with the rifling of a barrel (not shown), and housing portion 102 has a structure (eg, including longitudinal ridges 110, 112 and circumferential ridges 114, 116) configured to deform. on impact and thus release the marking compound contained therein, as described in more detail below.

As a starting point, the term marking projectile, as used herein, refers to the class of non-lethal practice ammunition characterized by its relatively low mass (and therefore low energy), and its capacity. to provide some visual indication of its point of impact, typically through the release of some form of marking compound through a more frangible forward portion. The various embodiments described herein relate to a polymeric or polymeric marking projectile, that is, a projectile that is at least partially manufactured using a polymeric plastic material.

Referring now to Figures 2 and 3, Figure 2 is a side view of marking projectile 100 in accordance with the illustrated embodiment, and Figure 3 is a corresponding cross-sectional view of marking projectile 100 that is generally aligned with the same. As mentioned above in connection with FIG. 1, the marking projectile 100 includes three coaxially aligned portions that extend from one end 210 (referred to as rear) to an opposite end 212 (referred to as forward or impact). In one example, marking projectile 100 includes base portion 101, housing portion 102, and metallic annular sealing component 103. As illustrated, the sealing component 103 is generally configured to secure the housing part 102 to the base part 101 and at the same time provide a seal between the two components. Various regions of the marking projectile 100 are delimited in FIG. 2, namely, regions 202-207 extending from end 210 to end 212. These regions will be mentioned in the description below.

ES 2 744 550 T3

As shown in Figure 3, a cavity 303 in housing portion 102 houses a suitable marking compound 302 - for example, a water, wax or oil based marking compound. In some embodiments, marking compound 302 is semi-viscous and fills a large portion of cavity 303 such that its mass is uniformly distributed around the central axis of the projectile (indicated by a dotted line). In this regard, it will be appreciated that Figure 3 merely presents an exemplary configuration (eg, size and shape) for marking compound 302, and is not intended to be limiting.

Marking projectile 100 further includes a rear cavity 304 configured to, among other things, receive an ejection force produced by ignition of a propellant. That is, the marking projectile 100 is configured to be incorporated into a cartridge of the type commonly used in connection with firearms, as is known in the art. For the sake of clarity, such cartridge components are not illustrated in the drawings.

The annular seal 103 can be implemented using a variety of structures and materials configured to secure the housing part 102 to the base part 101. For example, a ring-shaped structure (region 203 in Figure 2) can be provided to apply a radial compressive force (through, for example, plastic deformation) and thereby fix the housing part 102 to the base part 101. In one example, the annular seal 103 of the illustrated embodiment comprises a crimped metal ring. That is, as shown in Figure 3, and as further shown in the detailed view of Figure 4, the base portion 101 is partially overlapped, coaxially, by the front housing portion 102, and the crimped metal ring (103) has a non-crimp portion 312 at least partially incorporated (or otherwise engaged or secured) within the base portion 101, and a crimp portion 310 that applies radial compression (i.e., inward relative to the central axis) to an outer surface of the front housing portion 102.

The axial length of the sealing component 103 can be selected to achieve the desired level of projectile stability in light of other offsets. In one embodiment, for example, the sealing component 103 has an axial length (as seen in Figure 3) that is greater than about 5.0% of the total length of the marking projectile (that is, it extends from end 210 to end 212). In one embodiment, the sealing component 103 has an axial length that is between about 17% and 25% of the total length of the marking projectile 100.

The sealing component 103 can be manufactured from a variety of materials, but is generally a sufficiently malleable metal that it provides the desired level of radial crimp force, which can vary depending on the size and shape of the marking projectile. As used herein, the term "malleable" refers to the extent to which a material plastically deforms in response to compressive stress without fracture. In one embodiment, the sealing component 103 comprises a copper alloy having at least about 50% copper content, for example, at least about 65% copper content, and, as a further example, at least about 85% copper content. In addition, other metal alloys can be used, including, without limitation, steel, iron, tin, aluminum, gold, silver, platinum, tungsten, titanium, zinc, sintered metal, and the like.

An advantage of including the sealing component 103, in addition to its ability to seal the base portion 101 and the housing portion 102 together, is that its relatively high mass annular shape increases the gyroscopic stability of the marking projectile 100. In one embodiment, for example, the gyroscopic stability of the marking projectile 100 in the muzzle of the weapon is greater than about 1.3 times (preferably about 2.0 times in a 5.56 caliber projectile embodiment) than that of a Reference marking projectile, that is, a projectile that only includes the base part 101, the housing part 102, and the marking compound 302.

Crimped, the sealing component 103 generally has an outer diameter (region 203) that is less than the outer diameter of the housing part 102 and the base part 101. This prevents possible scratches from lenses, such as protective mask lenses, car paint and the like. It also prevents the sealing component 103 from engaging the rifling of the barrel.

In the illustrated embodiment, the base portion 101 includes a stepped circumferential conduction band region (region 202 in FIG. 2) configured to engage the barrel grooves and collect and remove debris from the barrel. This is illustrated in fig. 2 as two axial steps within region 202, starting from a high OD 231, to a lower diameter region, and then to another high OD 232. The region in the vicinity of the outer diameter 232 mates with the barrel rifling, and the region in the vicinity of the outer diameter 231 (which is preferably configured as a sharp leading edge, as shown) collects and removes debris from the barrel, including debris produced through the engagement of OD 232 with the flute. The outer diameter 231 will also, to some extent, match the rifling of the barrel. As illustrated, the conduction band region 202 will generally be the only part of the marking projectile 100 that mates with the rifling of the barrel, as it includes the regions of the marking projectile 100 with the highest outside diameter (Figure 2). .

The front housing portion 102 includes at least one circumferential guide band region (regions 204 and 206 in FIG. 2), separated by a body region 205 provided therebetween. Guide band regions 204 and 206 are configured to provide an aligned engagement of the polymeric base portion with the groove of the

ES 2 744 550 T3 cannon. That is, while regions 204 and 206 do not match the barrel groove (due to their smaller outer diameter compared to region 202), they may contact the inner surface of the barrel from time to time as it is translated and rotates through the barrel, thus keeping the shell 100 aligned within the barrel. Although only two guide band regions 204 and 206 are illustrated, any number of such guide band regions may be employed.

As mentioned above, the housing portion 102 includes one or more structural details configured to allow the marking projectile 100 to deform on impact and thereby release the marking compound contained within. In some embodiments, the housing portion 102 includes a number of longitudinal ridges 112 and 110 (regions 205 and 207 of FIG. 2), as well as one or more circumferential ridges 114 and 116 (region 205 of FIG. 2). The depth of the circumferential ridges 112 and 110 will vary depending on design factors, but in one embodiment, one or more of the ridges is at least about 25% of the thickness of the carcass portion 102. It has been found that the ridges Circumferentials 114 and 116 effectively act as fold zones and thereby assist longitudinal ridges 112 and 110 in opening during impact.

A variety of polymeric materials and manufacturing techniques can be used to form the base part 101 and the shell part 102. Since the base part 101 will generally not deform significantly during impact, it can be made from a polymeric material that is different from (and heavier than) the one used to manufacture the housing part 102. Suitable polymeric materials include, without limitation, acrylonitrile butadiene styrene (ABS), acetal, nylon, polycarbonate, polyethylene, polypropylene, polyvinyl chloride (PVC), and Teflon. The selected polymer preferably exhibits low permeability to help minimize moisture transfer through the body of the thin-walled projectile.

The various structural details of the carcass part 102 generally allow the carcass part 102 to form a mushroom (e.g., deform to form a generally mushroom shape) and thereby absorb the impact energy and release the marker compound into a particularly desirable pattern. In this regard, Figures 6-8 depict the progressive deformation of an exemplary marking projectile during impact, and Figure 9 illustrates a marking pattern resulting from impact in accordance with one embodiment.

More particularly, Figures 6-8 depict the deformation according to a computer-based model, and is presented simply as an example (but not necessarily a strictly realistic example) of how the shell portion 102 could deform on impact. As can be seen, as the impact progresses (due to contact of the leading surface 212 with a target, not illustrated), the ridges 110 and 112 gradually fracture to expose the marking compound contained within. The time and extent of this deformation can be modulated by the size and position of the circumferential ridges 114 and 116, as described above. Figure 9 shows the resulting marking pattern 900, characterized by radial segments (in this case, four radial segments) extending from the central contact point. However, it will be appreciated that the invention is not limited thereto and that the marking pattern 900 will vary depending on the number and size of the grooves incorporated in the housing portion 102.

A variety of fabrication and assembly methods can be employed to produce a marking projectile 100 as described above. In that regard, Figure 5 is an exploded view of the various components of the marking projectile 100. In accordance with one embodiment, the method includes the steps of (1) forming the base portion 101 so that it is configured to engage the rifling of the barrel; (2) forming the housing portion 102 to include a cavity 303 and have one or more structural features configured to deform on impact to expose the cavity 303 (as described in more detail above); (3) depositing, dispensing, or otherwise inserting marking compound 302 into cavity 303; (4) coupling base portion 101 to housing portion 102 (eg, inserting one component coaxially into the other); and (5) sealing the housing portion 102 to the base portion 101 with the metallic annular sealing component 103, for example, by providing a circumferential crimp to the sealing component 103 using any of a variety of conventional crimping tools known in the art. technique.

In some embodiments, the sealing component 103 and the base portion 101 are manufactured as separate components. However, in other embodiments, the sealing component 103 may be co-molded with the base portion 101, thus simplifying assembly.

In one embodiment, the base portion 101, the housing portion 102, the marking compound 302, and the sealing component 103 together form a 5.56mm projectile having a mass between about 0.25 and about 0.50. grams. Other projectile calibers that could benefit from the disclosed affair include, without limitation, 0.380 Auto, 0.40 S&W caliber, 7.62mm NATO and 9mm Parabellum. Such projectiles can have mass values ​​of up to 0.75 g.

Although at least one exemplary embodiment has been presented in the detailed description above, it should be appreciated that a large number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are examples only, and are not intended to limit the scope, applicability, or configuration of the disclosure in any way. Rather, the above detailed description will provide those skilled in the art with a convenient roadmap for implementing the exemplary embodiment or exemplary embodiments. It must be understood

ES 2 744 550 T3 that various changes can be made in the function and arrangement of the elements without departing from the scope of the disclosure as set forth in the appended claims.