Patent Application
20120247314
The present invention relates to improved ballistic baffles for deflecting bullets, such as at a shooting range. More particularly, the present invention relates to baffles having an impact layer (also referred to as an abrasion and impact layer) and one or more layers of energy dissipating material adhered on a backside of the impact layer to improve energy dissipation, reduce cost and/or to reduce baffle weight.
There are a variety of reasons for which individuals engage in shooting at a shooting range or similar facility. Many individuals will shoot to improve their proficiency in hunting. Law enforcement officials shoot on a regular basis to maintain their proficiency in the use of firearms so as to ensure their skills and promote safety. Shooting proficiency can be done using a number of different types of training facilities. One type of training facility used to improve shooting proficiency is the indoor shooting range.
Safety concerns at an indoor shooting range are particularly important because shooting range structures and ballistic projectiles are all enclosed at relatively close distances from the shooter. Thus, bullets deflecting from targets or other shooting range structures could threaten the safety of a shooter or others at the range if not properly controlled. Shooting ranges typically use a number of safety precautions to control the direction and deflection of bullets. In most indoor shooting ranges and some outdoor ranges, one such precaution is the hanging of ballistic baffles from the ceiling or other support structures along the shooting range at such an angle as to deflect stray bullets towards the bullet containment area at the back of the shooting range. This directs the bullets away from the shooter and away from the ceiling where penetration could cause a risk to others outside the building and where deflection could cause injury to others inside the building.
Ballistic baffles used for deflecting bullets in shooting ranges are commonly made of or include steel panels which are approximately three-eighths (⅜) inch (or 9.5 mm) thick. Hardened steel (or in some situations regular steel) may be used so that bullets do not penetrate the baffles and reach the ceiling or high walls where there may be a higher risk of a bullet exiting the building or deflecting towards the shooter or others nearby. Unfortunately, the use of the ⅜th inch (9.5 mm) hardened steel plate raises several concerns. For example, steel panels can be very costly and changes in steel prices can cause substantial variations in the cost to build a shooting range. (As used herein, about or approximately ⅜th inch (9.5 mm) (or other size) refers to plates of steel or other materials which are considered to be ⅜th inch (9.5 mm) (or other stated size) in industry even though exact thicknesses vary slightly.)
Additionally, the steel panels can be cumbersome because of the weight, requiring heavy reinforcement of the structure which supports the baffles. A panel 4 feet by 8 feet (1.22 m by 2.44 m) of ⅜ths inch (9.5 mm) steel weighs nearly 490 lbs. (222 kg). If five such panels are disposed in a linear array to form a 40 foot (12.2 m) wide baffle, the baffle weighs 2450 lbs. (1110 kg). If five rows of baffles are used on a shooting range, 12450 lbs. (5550 kg.) must be supported above the range.
Finally, steel panels may not provide optimal performance for a particular type of projectile deflection. While steel has very good abrasion and penetration resistance, it is not as good at avoiding deflection and/or compression. Additionally, in some situations it may be desirable to use softer grades of steel to keep costs down if they can be adequately enhanced to provide similar deflection characteristics to a hardened steel panel.
Thus, there is a need for ballistic baffles which are lighter, less expensive, and/or have improved performance characteristics over three-eighths (⅜) inch (approximately 9.5 mm) steel baffles while preventing bullet penetration and deflecting bullets away from the shooter.
It is an object of the present invention to create a baffle for containing projectiles. In accordance with one aspect of the present invention, a ballistic baffle may be made by adhering or otherwise attaching a layer of an energy dissipating material to the impact layer formed by an impact and abrasion resistant material.
In accordance with one aspect of the invention, a compressive resistant material may be attached to one side of an abrasion and impact resistant material forming an impact layer. The impact layer is intended to receive and deflect bullets or other projectiles and the compressive resistant layer is intended to strengthen the impact layer against bullet penetration and deformation of the impact layer by dissipating energy from the impact of a bullet. It will be understood that, unless stated to the contrary, that reference to a layer will include a single layer of a material with a given characteristic and to multiple layers with that characteristic.
In another aspect of the present invention, an impact absorption or damping material may be placed between the compressive resistant layer and the impact layer. The impact layer may be designed to receive and deflect bullet projectiles and the damping material and the compressive resistant layer may strengthen the impact layer against bullet penetration and at the same time dissipate energy from the impact of a bullet.
In accordance with another aspect of the present invention, a fragment containment material may be attached to a back side of the compressive resistant layer or damping layer. The fragment containment material may be configured to contain fragments of any projectiles which may penetrate the abrasion and impact resistant layer, the compressive resistant layer and any other layers which may be present.
The layers of material provide a baffle which can be lighter weight and/or have greater resistance to penetration than conventional baffles in some configurations. In other configurations, the composite baffle simply may be less expensive than a steel only baffle having similar bullet stopping/deflecting capabilities. In still other configurations, the composite baffle may provide improved performance for specific applications.
Various embodiments of the present invention are shown and described in reference to the numbered drawings wherein:
It will be appreciated that the drawings are illustrative and not limiting of the scope of the invention which is defined by the appended claims. The baffles shown may accomplish various aspects and objects of the invention. It is appreciated that it is often not possible to clearly show each element and aspect of the invention in a single figure, and as such, multiple figures may be presented to separately illustrate the various details of the invention in greater clarity. Similarly, not every embodiment need accomplish all objects or advantages of the present invention.
The invention and accompanying drawings will now be discussed in reference to the numerals provided therein so as to enable one skilled in the art to practice the present invention. The drawings and descriptions are exemplary of various aspects of the invention and are not intended to narrow the scope of the appended claims.
The present invention typically includes a material for receiving the abrasion and impact of a projectile, referred to herein as the impact layer. The impact layer may be backed by various energy dissipating layers of material. The energy dissipating layers may include a compressive resistant layer and/or a damping layer.
The impact layer may be formed of different materials which are suitable for receiving the abrasion and impact of a high velocity projectile, such as a bullet, with minimal wear or damage. In accordance with one aspect of the invention, the abrasion and impact layer is preferably steel plate which is thinner than traditional baffles. In other words, the layer of steel is less than ⅜th of an inch (9.5 mm). Thus, the steel may be, for example, between 1/16th and 5/16th of an inch (1.59 mm to 7.94 mm). This thinner piece of steel reduces weight by about 16-84 percent and renders the steel cost in the baffle substantially less than a conventional ⅜th inch (9.5 mm) steel plate. Depending on the desired use, a mild grade steel or hardened steel may be used. Other materials may also be used as discussed below.
The addition of a compressive resistant layer provides resistance to compression and bending, and stiffens the impact layer, thereby preventing excessive deformation and piercing of the impact layer by projectiles. The use of a good compressive resistant layer allows for use of an impact layer which is thinner than the traditional steel baffle.
Where a damping layer is used, the damping layer helps to dissipate energy caused by the impact of the projectile. The damping layer may be located between the impact layer and the compressive resistant layer. The damping layer may allow for some bending of the impact layer without transferring the bending to the compression layer. This can help prevent damage of the compressive resistant layer by damping and distributing the point loads which may occur from a bullet strike while still allowing the compressive layer to stiffen the impact layer and prevent a bullet from piercing or overly deforming the abrasion and impact layer.
Turning now to
The abrasion and impact resistant material forming the impact layer 7 may be selected from materials such as AR500 Steel (or other hardened steel), soft steel (for certain applications), aramid fiber (KEVLAR), or ceramics. By replacing a single panel of ⅜th inch (approximately 9.5 mm) steel with ⅛th inch (3.2 mm) steel, a weight reduction of approximately 320 lbs. (145 kg) is achieved in steel weight. Additionally, the cost of steel in the baffle may be reduced nearly 66 percent.
The compression resistant material forming the compressive resistant layer 9 may be selected from a variety of materials including: concrete, including, but not limited to high PSI and reinforced concrete, concrete board formed by nesting mesh in concrete (commonly referred to as backerboard and sold under the trademarks DUROCK (USG), HARDIEBACKER (James Hardie Industries) and WONDERBOARD (Custom Building Products), for example. The compression resistant material may also be steel including either hardened steel or regular steel, rubber, fiber glass materials, wood, such as wood pieces, particle board, OSB and the like, carbon fiber, KEVLAR, or ceramics.
As an example of weight savings, a sheet of HARDIEBACKER backerboard (about 0.4 inches (about 10.2 mm) thick) weighs approximately 83 lbs. (37.6 kg). Thus, a compressive resistant layer 9 formed by three sheets of backerboard could be used behind an impact layer 7 of ⅛th (3.2 mm) steel while still reducing weight over a conventional baffle and having a thickness three times that of a conventional baffle. While ¼th inch (6.4 mm) of steel is lost, it is replaced by about 1.2 inches (about 30.6 mm) of mesh impregnated concrete board and a lower overall weight. This enables the baffle to remain generally rigid when impacted by a bullet while saving both cost and weight.
The compressive resistant layer 9 may be adhered or attached to the impact layer 7 using customary methods of adhesion, such as epoxy, glue, riveting, etc., as applicable to the particular energy dissipating material used as the compressive resistant layer, i.e., backing material. Additionally, as noted above, the compressive resistant layer 9 may include multiple pieces of compressive resistant material 9 which may use various methods for attaching them to each other including epoxy, glue, riveting, screws, etc.
In stopping a bullet, two factors must be considered. First, it is important to contain the bullet without penetrating the stopping material and second, the energy from the bullet must be dissipated. With a conventional baffle, this is done relatively easily because the hardened steel is difficult for the bullet to penetrate and the mass of the ⅜th inch (9.5 mm) (or greater) hardened steel will dissipate the energy. In accordance with the present invention, it has been found that a thinner piece of hardened steel or other material can stop a bullet without the bullet penetrating the material if a compressive resistant material or other energy dissipating material is attached to the impact layer 7 to help reduce deformation and dissipate the bullet's energy. Thus, a baffle can be made which is lighter weight than conventional baffles, reducing the steel (or other abrasion and impact material) cost and reducing the amount of support structure needed to hold the baffles above the range. In addition to or in the alternative, the use of less steel may simply reduce the cost of the baffles, as less expensive materials can be used as a backing to the impact layer 7.
While shown in
Turning now to
Similar to the discussion above, if hardened steel is used for the impact layer 7, the impact layer may be less than ⅜th inch thick and, while not required, may typically be between about 1/16th and 5/16th inch thick (about 1.6-7.9 mm), and more preferably between about ⅛th inch (3.2 mm) and ¼th inch (6.4 mm) thick, with about ⅛th inch (3.2 mm) currently being most preferred and shown in
Each of the plurality of layers of energy dissipating material, e.g., the impact absorption material 13 and 15, may be made of the same energy dissipating material as the other layers, or a combination of materials may be used. It will be appreciated that there is overlap between the materials which may be used in a compressive resistant layer and a damping layer. Which forms the compressive resistant layer may depend on the materials selected. For example, oriented strand board (OSB) may serve as a compressive resistant layer when placed against a rubber, but may serve as a damping layer when placed against concrete backerboard.
The energy dissipating material may be adhered to the impact layer 7 and/or to the other layer(s) of energy dissipating materials using customary methods of adhesion, such as epoxy, glue, riveting, etc., as applicable to the particular energy dissipating material used as the backing material. Additionally, the other materials may be formed directly on the impact layer 7 so that they adhere with or without additional adhesives, etc.
Turning now to
The baffle 17 may also include a fragment containment material forming a containment layer 19 to decelerate or stop any projectile fragments which may have penetrated the other layers. The fragment containment material 19 may include steel, rubber, wood, and/or composites or structural fibers such as carbon fiber, aramid fibers (KEVLAR), or fiberglass. In some cases, a bullet may penetrate the impact layer 7 if, for example, a higher velocity round is used than for which the shooting range was designed. Even in such a case, however, the bullet will typically have dissipated significant energy before penetrating the impact layer 7, absorption or damping layer 13 and compressive resistant layer 9, and can be reliably contained by the fragment containment layer 19.
As before, if a hardened steel panel is used for the abrasion and impact resistant layer 7, the steel panel would be less than ⅜th inch (9.5 mm) thick and, while not required, may desirably be between ⅛th inch (3.2 mm) thick and ¼th inch (6.4 mm) thick. The material of the absorption or damping layer 13 may be made of the different energy dissipating materials as discussed above with respect to
While shown in
It will be appreciated, that the present invention provides a wide variety of combinations which may be used to make a baffle for containing stray bullets and other projectiles. The following are examples of baffles which could be used. They are for demonstration purposes and are not intended to limit the scope of the invention;
An abrasion and impact material formed from ⅛th inch (3.2 mm) of AR-500 steel is backed with 2 inches (50.8 mm) of OSB adhesively attached to the AR-500 steel.
An abrasion and impact material formed from 1/16th inch (1.6 mm) AR-500 steel is backed with an impact absorption material of ¾th inch (19.2 mm) plywood and a compressive resistant material of ¼th inch (6.4 mm) rubber which is backed by containment material of 1/16th inch (1.6 mm) of AR-500 steel.
A ¼th inch (6.4 mm) panel of hardened steel is bonded to a ½ inch (12.7 mm) layer of 10,000 psi concrete.
A ⅛th inch (3.2 mm) panel of hardened steel is bonded to 2 inches (50.08 mm) of fiberglass composite, which is boned to a ¼th inch (6.4 mm) of aramid (KEVLAR) composite.
A ¼th inch (6.4 mm) panel of hardened steel is attached by epoxy to a ½ inch (12.7 mm) layer of carbon fiber.
The same panel of Example 5 with a 1 inch layer of rubber adhesively attached to the carbon fiber.
A 1/16th inch (1.6 mm) panel of hardened steel attached to a ¼th (12.7 mm) inch layer of fiberglass, which is attached to 1.5 inches (38.1 mm) of plywood;
A ⅛th inch (3.2 mm) panel of hardened steel is backed by two sheets of mesh/concrete backer board (HARDIEBACKER) having a combined thickness of approximately 0.8 inches (21 mm).
While numerous examples can be given based on the variety of material which are discussed above, combinations of the following are presently believed to be preferred for various applications. Other applications (high velocity rounds versus pistol round) may have different preferred combinations.
2 mm (between about 1/16th and 1/12th inch) or 4 mm (between about approx. ⅛th and ⅙th inch) sheets of AR-500 for the impact and abrasion layer, backed with:
Turning now to
The suspension members 38 typically engage the connectors 40 so that the baffles 42 are disposed in an orientation between vertical and horizontal in order to deflect bullets which may be fired at too high of an angle back toward a collection system 46, such as a berm trap, a bullet containment chamber or other bullet containment system.
The baffles 42 may be formed in the manner of baffle 5 of
The compressive resistant layer 9 may be made from the variety of materials discussed above, although two or three sheets of 0.4 inch (10.1 mm) backerboard (mesh/concrete) is presently preferred. This results in a lighter weight, less expensive baffle.
The second and fourth baffles 42 are formed like baffle 11 with an impact and abrasion layer 7, and energy dissipating layers 13 and 15, which may be formed from foam, rubber, wood or a variety of other materials as discussed above either as damping layers, compressive resistant layers or a combination thereof.
The third baffle 42 is formed like baffle 17 with an impact 7, a damping layer 13, and a compressive resistant layer 9. It may also include a fragment containment material 19 to contain any projectile which is able to penetrate through the impact and abrasion layer 7. The various materials used in each of the baffles may be those discussed above or other materials which perform similar functions.
It will be appreciated that the baffles can be tailored to the needs of the range. For example, the rearward most baffle may take the most rounds because it is close to the bullet trap 46 and is at the closest angle to the target 50. Thus, the rearward most baffle may be made the strongest with a ¼th inch (6.4 mm) AR-500 plate impact layer 7 with an energy dissipating damping layer 13 and multiple sheets of backer board forming a compressive resistant layer 9.
In contrast, the first baffle is least likely to be hit and may use only a 1/16th inch (1.6 mm) sheet of hardened steel (or a thicker piece of soft steel) with a couple of pieces of concrete board, OSB or the like. Thus, a customized baffle system may be provided which has less weight, less cost and/or better performance characteristics.
There is thus disclosed an improved ballistic baffle for use on indoor and other shooting ranges and shooting training systems. It will be appreciated that numerous changes may be made to the present invention without departing from the scope of the claims. The appended claims are intended to cover such modifications.
The present application claims the benefit of U.S. Provisional Application Ser. No. 61/435,971, filed Jan. 25, 2011, which is incorporated herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61435971 | Jan 2011 | US |
