Patent Application
20240167794
The invention relates generally to a new composition of matter for use as a projectable, frangible object, and more particularly to a shooting activity, such as trap, skeet or sporting clays, in which the target is formed from a low toxicity material that can be essentially or practically nontoxic.
A typical shooting target, often known as a “clay pigeon,” can be used for various shooting activities, such as a trap, skeet, sporting clays, and the like, is shown as a target 10 in
Shooter 30 aims a shotgun 40 at flying target 10 and typically fires a pattern of shot shell pellets 50 from shotgun 40 in the direction shooter 30 expects target 10 to fly, with the intent to intercept and strike target 10 with as many of the shot shell pellets fired from gun 40 as possibly. The intent of shooter 30 is to shatter target 10 into as many and as small fragments and particles as possible. Thus, to increase the enjoyment of shooter 30, target 10 should be sufficiently frangible that it will shatter when struck by a relatively low number of pellets 50.
It can be frustrating to a shooter, when they observe that they have hit target 10 with at least some of shot 50, but did not break the target. Occasionally, an unbroken target will be struck by a small number of shot shell pellets 50, but remain unbroken. With respect to unbroken targets hit by at least one shot pellet, as a general rule, it is desirable for less than 50%, preferably 70 or 80% of the unbroken targets to have been hit by three or more shot shell pellets. Shot shell pellet strikes on unbroken targets can be observed by examining unbroken targets for shot shell pellet strike markings. It is preferred that no more than 25% of unbroken targets will be hit by three or more pellets, and remain unbroken. Most preferably, only 10% or fewer unbroken targets will have been hit by three or more shot shell pellets, and remain unbroken.
It is also preferred that target 10 is able to be “smoked,” i.e. reduced to a cloud of powder or small fragments when hit by a considerable number of shot shell pellets 50. In general, at least about 50%, preferably over 75% of the targets broken from shot 50 should break into five or more pieces. With the best targets, the percentage broken into five or more pieces should be over about 90%.
In addition to shattering in a consistent manner, target 10 must be sturdy enough to remain intact and undeformed, despite being subjected to considerable forces when launched by target launcher trap 20. Upon leaving the launcher, a target is commonly traveling at speed over 60 mph. A target is unacceptable if over 5%, even 2% of those targets break apart as they are being launched. Targets 10 must also be sturdy enough to be stacked in boxes, jostled during transportation and stored in various hot and cold environments, while substantially maintaining their shape, so that they fly properly and can be launched for use. It is not satisfactory if even about 5%, even 2% of the targets crack or deform when stored for over 30 days at temperatures above 90° F. and below 32° F. Preferably, this number should be below about 1%. Preferred targets should be able to withstand exposure to temperatures of 130° F., 140° F., even 150° F. and above for over 5 hours, a week, even 30 days, without experiencing observable deformation and/or any affect to flight or breakage characteristics.
A standard commercial target for trap, skeet and sporting clay shooting is formed with a petroleum, coal tar or sulfur-based resin, and a filler, such as clay, talc, ash, limestone and the like. As used herein, the term “pitch” will refer to both petroleum and coal tar based resins. A conventional target is approximately 95-102 g, about 4.25 inches in diameter, and approximately 1.12 inches high. Some specialty, International, and sporting clay targets can have slightly different dimensions.
Skeet, trap and other sporting clay target shooting activities are commonly conducted outdoors. When conventional pitch-based targets shatter and fall to the ground, they can cause various environmental concerns. For example, there is some concern that animals will be harmed if they eat any of the target fragments.
Over the years, various proposals have been made to produce shooting targets with fewer environmental and toxicity concerns. Many of these have proved to be unsatisfactory, either because the targets did not break well, were not sturdy enough, or deformed during storage. Others undesirably impacted the land to which they fell.
Accordingly, it is desirable to provide an improved target and method of formation, which overcomes shortcomings of the prior art, and breaks as well or better than a conventional pitch target.
Generally speaking, in accordance with the invention, targets, target compositions, and methods of target manufacture are provided. Targets in accordance with the invention will typically shatter into a large number of fragments, even when hit by a small number of shot shell pellets. Moreover, the targets can be essentially or practically nontoxic, with an LD50 of 10,000, 15,000 mg/kg or greater. Also, they should have a minimal impact to the land on which they fall. Targets in accordance with the invention should be able to withstand exposure to temperatures of 130° F., 140° F., even 150° F. and above for over 5 hours, a week, even 30 days, without experiencing observable deformation and/or any effect to flight or breakage characteristics.
A breakable shooting target in accordance with the invention can be formed from a composition comprising: a binder component, a binder modifier, a viscosity modifier, and a filler. Carbon black or other pigments can be added for color. The binder can be selected from one or more natural fatty acids or fatty acid derivatives. Preferably, these will have a crystallization point below about 72° C. The binder modifier can be selected from one or more metal oxides. The viscosity modifier can be selected from one or more plant based or other natural resins. The filler component can be selected from various powders, such as powdered limestone, other sources of calcium carbonate, and so forth.
The composition can be formed into a melt, then molded and cast into a disk shape. The target should be cast into a state of sufficient strength and brittleness, that the target can be launched from a target launching trap without breaking, fly through the air in a reproducible, consistent path or pattern, and when hit with multiple shot shell pellets fired from a shotgun, shatter into multiple pieces. Preferably, accurate hits will turn the target into a cloud of smoke.
Unless specified otherwise, all composition percentages herein are on a weight basis. When present, the viscosity reducer or brittleness additives can comprise about 3-10%, preferably 4-9% of the composition. The base binder can comprise about 8-15%, preferably 10-14% of the composition. The metal oxide can comprise about 0.7-1.5%, preferably about 0.75-0.916% of the composition.
Preferred targets suitable for shooting sports comprise pine resin, stearic acid, calcium oxide, and filler. They can be cast into a disk of sufficient strength and brittleness, that when launched from a trap into the air and shot at with shot shell pellets from a 12 gauge shotgun fired at least 25 yards behind the trap, no more than 10%, preferably 5% of hit targets (hit by 3 or more shot shell pellets) will not break.
Targets in accordance with the invention are able to be “smoked,” i.e. reduced to a cloud of powder or small fragments when hit by a considerable number of shot shell pellets. At least about 50%, preferably over 75% of the targets broken after being hit by 10 or more shot shell pellets will break into five or more pieces. In more preferred embodiments of the invention, the percentage broken into five or more pieces should be over about 90%.
In a preferred manufacturing method, a mixture of fatty acid and metal oxide is stirred continuously at a temperature between 230-300° F. Calcium stearate can be produced through dehydration synthesis, by heating and mixing stearic acid and calcium oxide. A visible chemical reaction can occur, believed to convert the fatty acid into the salt(s) of the conjugate fatty acid. Due to the blend of fatty acids used and the relatively low ratio of metal oxide (less than stoichiometric requirements of complete conversion) a blend of fatty acids and conjugate bases is believed to form. This blend of fatty acids and conjugate bases (such as octadecanoate) following the chemical reaction possess a higher melting point than the original fatty acids. The melt point is typically in the range of 275-325° F. A melt point of 290-300° F. is preferred. This higher melting point base binder is preferred to provide a material that has enhanced application performance (e.g. breakability/brittleness/frangability during shooting) and thermal durability properties necessary for shipping, storage, and warm climate exposure.
Accordingly, it is an object of the invention to provide an improved target composition, target, and method of manufacture. Another object of the invention is to provide a non-toxic target that breaks as well or better than a conventional pitch target.
Still other objects of the invention will in part be obvious and will, in part be apparent from the specification and drawings. The invention accordingly comprises the composition, device and method which will be exemplified in the structures and methods hereinafter described, and the scope of the invention will be indicated in the claims.
For a fuller understanding of the invention, reference is made to the following description in connection with the accompanying drawings, in which:
The drawings are presented for purposes of illustration only. They are not necessarily to scale, and are not to be interpreted as limiting.
The invention relates to a shooting activity, such as trap shooting, skeet shooting, sporting clays, and the like, having a reduced environmental impact. Targets in accordance with the invention can be substantially pitch free, can be formed of essentially non-toxic components, and can be stored for extended periods of time under adverse environmental conditions without deformation. The targets can still be launched and broken properly, even when hit by a minimal number of shot shell pellets. Targets in accordance with preferred embodiments of the invention can lack pitch or other environmentally undesirable ingredients.
In preferred embodiments of the invention, a shooting target can be formed with a non-toxic and/or non-environmentally adverse binder. Preferred binders are readily mixed with suitable aggregate fillers. Molding is a preferred target forming method. Accordingly, preferred binders should be readily meltable. Upon mixing the aggregate filler and binder, the mixture should exhibit excellent forming and flowability characteristics for proper manufacturability.
In preferred methods, the binder is heated to form the molten material and solidifies during cooling after being injected into the mold. Once cured, the newly formed targets should exhibit properties which promote removal from the mold. The produced target should exhibit sufficient strength to survive being launched yet, paradoxically, provide excellent shatter results when contacted in flight or otherwise by as few as three shot shell pellets. Further, the material composition of the target should not warp or otherwise deform at normal storage temperatures to provide consistent “flight” characteristics. Targets in accordance with the invention should maintain geometric integrity at temperatures in the range of 150°−180° F. for 1-4 weeks or longer.
The LD50 of targets in accordance with the invention should be over 10,000 mg/kg, preferably over 15,000 mg/kg, with a “relatively harmless” determination on the Hodge and Stener scale. Other toxicity studies that resulted in an “essentially” or “practically” Non-Toxic determination include a fresh water algae study, a seedling emergence study on ryegrass, and an acute toxicity screening on earthworms.
The invention relates to the selection and processing of a suitable binder and modifiers that create a target that is able to be manufactured, stored for prolonged periods in elevated temperatures (at or up to 150° F., preferably at least 165° F.), launched from a trap device, exhibit sufficient breakability even when impacted with a low number of projectiles, exhibit low/non-toxicity with an LD50>10,000 preferably >15,000 mg/kg.
Suitable binders and modifier combinations are included in the range of about 14-24% by weight. Preferred compositions include about 14-18% by weight of the mix of binder and filler.
Fillers are utilized to create the desired final product. Calcium carbonate, e.g., limestone in a powdered form (>90% passing the U.S. Mesh size 100) is a preferred filler. Other suitable fillers include gypsum, clays, silicates, aluminates, sulfates, and other predominately inorganic powders. The fillers can be included at approximately, 70-86% by weight.
The base binder is preferably produced from a fatty acid, such as palmitic acid, stearic acid, myristic acid, or a blend of multiple fatty acids. Stearic acid is preferred. The fatty acid can be derived from tallow, vegetable oils, palm oils, or other bio-based materials. The fatty acid typically should possess a titre in the range of 30-72° C., preferably in the 50-70° C. range. Titre is the point at which a fatty acid will crystalize. The heat of crystallization causes a temperature rise.
Fatty acids, such as stearic acid, have been studied and identified as polymorphs. It is believed that the specific chemistry and processing conditions determine the final crystalline form of the fatty acid. This crystalline form typically influences the properties of the final clay target product.
Pitch is amorphous and a pseudo solid or a liquid that does not flow. Unlike pitch, the fatty acid component of the base binder should be in a crystalline form. The benefit of a crystalline base material is that when modified, it provides improved heat resistance until melt point. Amorphous materials such as pitch exhibit plastic properties and will begin to deform during heating long before reaching the identified softening point of the material. In contrast, crystalline materials will hold their shape for longer periods, even as the melt point is being approached.
The base binder in accordance with the invention is advantageously modified through a chemical reaction with a metal oxide. Preferred metal oxides include iron oxide, copper oxide, zinc oxide, magnesium oxide, and calcium oxide. It is preferred that calcium oxide is utilized. The ratio of calcium oxide to fatty acid is one way to control the chemical modification. The calcium oxide should be added at a 3-10% ratio by weight of fatty acid. It is preferred that the calcium oxide is added at 7-9.5% by weight of the fatty acid. All percentages used herein are by weight, unless indicated otherwise.
In a preferred manufacturing method, this mixture of fatty acid and metal oxide is stirred continuously and then heated to a temperature of about 275-300° F., preferably about 290-300° F. A visible chemical reaction occurs which is believed to convert the fatty acid into the salt(s) of the conjugate fatty acid. Due to the typical blend of fatty acids used and the relatively low ratio of metal oxide (less than stoichiometric requirements of complete conversion) it is believed that a blend of fatty acids and conjugate bases form. This blend of fatty acids and conjugate bases (such as octadecanoate) following the chemical reaction possess a higher melting point than the original fatty acids. The melt point is typically in the range of 175-225° F. A melt point of 190-210° F. is preferred. This higher melting point base binder is preferred to provide a material that has enhanced application performance (e.g. breakability/brittleness/frangability during shooting) and thermal durability properties necessary for shipping, storage, and warm climate exposure.
Viscosity modification is advantageous for manufacturability and application performance. Examples of viscosity modification include sugar alcohols (glycerol, isomalt, xylitol), natural waxes (soy wax, carnauba wax, etc.), paraffin waxes, petroleum derived waxes, surfactants, and natural resins (pine resin, gum rosin, glycerol esters, rosin, Greek pitch, rosin ester, and esters of wood). Typically, viscosity modifiers are added at between 0.1-15%, depending on the type of modifier utilized. The timing of viscosity modification addition with respect to the chemical reaction of the fatty acid and metal oxide may result in chemical changes to the viscosity modifier.
Biopolymers are an advantageous additive for the promotion of desired mechanical properties and for enhancing the environmentally impacting properties of the target. Biopolymers such as starches are advantageously added to enhance the breakability (e.g. the performance of the clay target during shooting). Starches are comprised of amylose and amylopectin, and the ratio of amylose and amylopectin varies based on the source of starch. For example, waxy corn or waxy maize starch contains very high levels of amylopectin, as do waxy potato starches. Beyond the natural form of starch, the biopolymer can be modified, which affords changes in performance during manufacturing and end-product properties. Natural starches such as corn starch and potato starch may increase desirable performance characteristics of the clay target. Modified starches, such as pre-gelled corn starch and acid modified starches offer property changes during manufacturability. However, high amylopectin starches are preferred for the mechanical properties imparted in the clay target. Biopolymer content, such as starches, can be added in the range of 0-25% by weight of the base binder.
The following Examples are for illustration and are not to be interpreted as limiting:
Ingredients for Use During Target Manufacture
Preferred ingredients for targets in accordance with the invention:
Stearic Acid is an acceptable example of a fatty acid, which is essentially a long hydrocarbon chain containing a carboxyl group at one end and a methyl group at the other.
Calcium Oxide is a white caustic alkaline solid, commonly produced in the form of quicklime.
Calcium stearate can be produced through dehydration synthesis, by heating and mixing stearic acid and calcium oxide:
2C17H35COOH+1CaO→1(C17H35COO)2Ca+1H2O*
Description of Reaction:
Steps:
This process is exothermic and the temperature of the mix typically rises.
It is believed that forming the calcium stearate in this manner leads to improved crystallinity, which leads to improved target characteristics, including both heat resistance and breakability.
Formulation of Blend Following the Reaction:
Steps:
3. Add calcium carbonate gradually, allowing the material to maintain temperature and become homogenous.
One of the most important characteristics of a target is how well it launches, flies, and then breaks, even when hit by a small number of shot shell pellets. The following shooting tests were performed with targets made in accordance with the invention. Shooters were standing over 25 yards (about 27 yards) from the launching trap. Often, shooters will stand closer to the trap, such as 16 yards or less, which makes it easier to break the targets. At some competitions, including the examples herein, the shooters stand 27 yards behind the trap. These targets were considered environmentally friendly and essentially nontoxic. Unbroken targets were caught in a tarp, examined for shot shell pellet marks and the number of shot shell pellets that had hit, but not broken the target, was recorded.
Shooting for Example 3 was conducted on an outdoor American trap field from the 27 yard line with full choke 12 gauge shotguns. Shot shells had a 2¾ inch shell length, 7½ shot size shell load, and a muzzle velocity of 1250 feet per second. In evaluating the breakage performance of targets in accordance with the invention, it cannot be reasonably expected that targets hit by 0, 1 or 2 shot shell pellets will break. Therefore, as used herein, a missed target is an unbroken target hit by 0, 1 or 2 shot shell pellets. A hit target is a target that was (1) broken by at least one pellet; or (2) hit by 3 or more pellets and remained unbroken.
As can be seen, the targets of Example 3 performed as well as or better than conventional pitch targets. Of 400 targets launched, 58 were considered misses, i.e., hit by 0, 1 or 2 shot shell pellets, based on visually examining unbroken targets for pellet strike marks. That left 342 “hit” targets. Of those 342 hit targets, only 6 (1.75%) did not break. Thus, 336 of 342 hit targets (>98%) were broken. This small percentage of hit (by 3 or more shot shell pellets without breaking) but unbroken targets is characteristic of a high performing target. Acceptable targets in accordance with the invention are constructed with sufficient strength and brittleness, such that when launched from a trap and shot at with shot shell pellets, at least 90% of “hit” targets will break. It is preferable to construct the targets such that at least 95% of hit targets will be broken. In general, the shooting performance of targets in accordance with the invention was indistinguishable or better than pitch targets.
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 carrying out the above method and in the devices and compositions set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.
