The present invention relates to firearms, and more particularly to a chemical composition that reacts to produce anti-fouling agents upon discharge of a firearm.
Modern firearms utilize a brass cartridge containing a primer, gunpowder, and a bullet. A firing pin struck by the firearm's hammer strikes the primer, which in turn ignites the gunpowder. The resulting gas pressure drives the bullet forward out of the firearm through the barrel. Every time the gun is fired, various types of fouling residues are deposited within the barrel, chamber, action, and magazine area. Carbon residue results from the combusted powder. Copper residue results from copper-jacketed bullets. Lead residue results from lead bullets. Shotguns also have plastic residue resulting from the plastic wads from shotshells. Severe fouling can result in numerous undesirable effects. These include misfeeding of rounds, decreased muzzle velocity, and decreased accuracy. Salts in the primer and/or gunpowder are also corrosive, which can cause considerable damage to a firearm if they are not periodically removed.
The traditional approach to avoiding the negative effects of fouling is to at least clean the barrel of a firearm as often as after every shooting session by removing residue using various chemicals and cleaning patches. However, this is a time-consuming process that is especially lengthy for semi-automatic and automatic firearms with a bolt carrier group, which requires thorough disassembly of the firearm to reach and remove all the fouling.
To address the time-consuming nature of traditional firearm cleaning techniques, various cleaning systems have been developed that attempt to clean the firearm through normal use, although with associated disadvantages. These include:
Therefore, a need exists for a new and improved gas propelled munitions anti-fouling system that provides anti-fouling agents while permitting normal operation of the firearm. In this regard, the various embodiments of the present invention substantially fulfill at least some of these needs. In this respect, the gas propelled munitions anti-fouling system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of providing a gas propelled munitions anti-fouling system that provides anti-fouling agents while permitting normal operation of the firearm.
The present invention provides an improved gas propelled munitions anti-fouling system, and overcomes the above-mentioned disadvantages and drawbacks of the prior art. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide an improved gas propelled munitions anti-fouling system that has all the advantages of the prior art mentioned above.
To attain this, a preferred embodiment of the present invention comprises a case having an open forward mouth end, a rear end, and an interior, the rear end defining a pocket that receives a primer and a passage communicating between the pocket and the interior of the case, a quantity of propellant received within the interior of the case, a quantity of anti-fouling composition received within the interior of the case, and a bullet having a rear portion inserted into the open forward mouth end of the case. The anti-fouling composition may have at least one salt and at least one acid. The acid may be anhydrous. The salt may be sodium chloride or sodium nitrate. The acid may be anhydrous citric acid. The anti-fouling composition may have at least one abrasive. The abrasive may be stannic acid. The anti-fouling composition may be 50% salt by weight and 50% acid by weight. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims attached.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated.
The same reference numerals refer to the same parts throughout the various figures.
An embodiment of the gas propelled munitions anti-fouling system of the present invention is shown and generally designated by the reference numeral 10.
The pellets 528, 530, 536 utilize the propellant 26 to partially or fully sequester the anti-fouling composition 28, thereby preventing the anti-fouling composition from interacting with at least a portion of the propellant and potentially altering properties during storage. In addition, the propellant is on the exposed surface of each pellet. So, when each pellet is ignited, the flame front goes to the next pellet's external propellant coating, and propagates more effectively. Encapsulation of the anti-fouling composition also eliminates the possibility of separation or settling of separate chemical layers. The ammunition manufacturing process requires no changes from what is done with a conventional cartridge. The encapsulated propellant is substituted for the standard propellant powder.
If it is determined the addition of the anti-fouling composition 28 into the center core of the pellets 528, 530, 536 takes up too much volume when implemented with traditional pistol or rifle propellants, then a more energetic propellant can be used to compensate for the reduction of propellant volume displaced by the anti-fouling composition. If the cost of the anti-fouling composition is less than the cost of the propellant it displaces, the cartridge cost including the anti-fouling composition may be the same or lower than a conventional cartridge despite the addition of the anti-fouling composition.
The squib round 700 of the current invention is particularly desirable for use in applications where squib rounds are used repeatedly in a gas-powered device, such as a stores release on an aircraft that uses either the squib gases directly or to actuate a piston assembly to perform a mechanical operation. Examples of mechanical operations include releasing a latch, ejecting an object, or performing a sequence of operations such as releasing a latch and subsequently ejecting an object. Other examples include creating the illusion of a bullet strike as a motion picture special effect, and the launch of a counter measures payload from a counter measures dispenser that is either ground-based or installed on an aircraft or ship. In these applications, fouling from the squib gasses leaves residue that must be removed to ensure continued operation when a replacement squib round is subsequently discharged.
An example of such an application is illustrated in
The counter measures round 770 is loaded into a counter measures dispenser unit 750 for use. A typical counter measures dispenser unit is shown in
Several formulations of anti-fouling composition are suitable for use with the gas propelled munitions anti-fouling system of the present invention. These include:
Each of the anti-fouling composition formulations consists of a mixture of at least one salt and one acid. A third abrasive component, such as stannic acid, is added to the anti-fouling composition when the propellant to be used with the anti-fouling composition does not already contain an abrasive (some gunpowders already include stannic acid). Any suitable salt/acid composition can be used with the present invention. The abrasive is used for its polishing properties. Stannic acid (hydrated particles of tin dioxide) of a specific particle size and hardness to provide a desired abrasiveness can be obtained using the method disclosed in U.S. Pat. No. 4,048,294 to Glosky, et al.
For a 9 mm round having a bullet weight of 115 grains using a quantity of anti-fouling composition premixed with propellant, the anti-fouling composition portion of the mixture is 20% by weight of salt, 20% by weight of acid, and 1% by weight of abrasive, with the remainder being 59% by weight propellant. For rounds of a different caliber or bullet weight, the quantities of propellant and anti-fouling composition are adjusted appropriately, with a higher proportion of propellant or a more energetic propellant being used for larger caliber and/or heavier bullets.
Testing of all three formulations has occurred by firing 75 or 300 rounds before cleaning the firearm. Compared to an identical firearm firing cartridges that are otherwise the same except for the presence of the anti-fouling composition within the cartridge, cartridges including the anti-fouling composition of the present invention had a visible reduction in the amount of residue in the barrel, a decrease in the amount of weight gained by the barrel, and visibly less residue being present on the first cleaning patch run through the barrel. In one test, a barrel firing 75 normal rounds omitting the anti-fouling composition gained 0.7 grains, while a barrel firing 75 rounds with the anti-fouling composition gained only 0.4 grains, providing evidence that the anti-fouling composition reduced the deposition of fouling residue within the second barrel. The best performing formulation of the three tested thus far is Formulation #3 when used with a gunpowder including stannic acid (tin dioxide), specifically Hodgdon® CFE Pistol Powder manufactured by Hodgdon Powder Company of Shawnee, Kans. Testing with a flake powder propellant (Bullseye® manufactured by Alliant Powder of Lewiston, Id.) showed reduced anti-fouling properties of the formulations compared to alternative powder propellants. When used with a gunpowder omitting stannic acid or another suitable abrasive, Formulation #3 is modified by subsequently adding 2% by weight stannic acid or another suitable abrasive. In the absence of an abrasive such as stannic acid in either the anti-fouling composition or the propellant, the anti-fouling properties of the current invention are reduced.
Testing of the three formulations for their barrel corrosion properties has also occurred. Formulations #1 and #2, which use Sodium Chloride, revealed some visible corrosion of the gun barrel after resting without cleaning for two months. Formulation #3, which replaces the Sodium Chloride with Sodium Nitrate, showed no visible barrel corrosion at six weeks after having fired 75 rounds without cleaning. An additional ten rounds were then fired, and the gun rested an additional two months without cleaning. A second inspection also showed no visible barrel corrosion.
The gas propelled munitions anti-fouling system of the present invention's use of an otherwise normal, conventional round with a novel anti-fouling composition provides numerous benefits compared to prior art approaches. The present invention applies anti-fouling agents to every portion of the firearm the exhaust gases reach, not just the barrel. The anti-fouling composition operates in rounds with standard bullets without adversely impacting performance, so the anti-fouling composition can be used every time a round is fired with any caliber of firearm with both live rounds and blanks. The present invention has no mechanical parts or liquids, and instead relies upon anti-fouling agents resulting from a chemical reaction occurring between the anti-fouling composition and the ignited propellant while the propellant combusts. The resulting anti-fouling agents travel down the barrel with the propellant gases, thereby treating the barrel. If the firearm uses the exhaust gas to operate a shell ejector, then the anti-fouling agents also travel to those additional areas exposed to the exhaust gases (the breach and magazine area). In semi-automatic and automatic rifles, the exhaust gases and anti-fouling agents travel through the gas tube into the bolt carrier group gas cylinder and the magazine area. Thus, all the areas of the firearm that would normally be fouled by the exhaust gases are instead simultaneously exposed to the anti-fouling agents of the present invention.
The anti-fouling composition of the present invention can be incorporated into cartridges and shotshells with minimal or no change to existing manufacturing processes, resulting in an affordable selling price. The present invention also has the potential to reduce cleaning time and frequency, thereby reducing firearm operating costs and extending the life of firearm components normally subjected to fouling.
While a current embodiment of a gas propelled munitions anti-fouling system has been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. For example, any suitable salt can be used with the present invention, either alone or in combination, including ammonium nitrate, calcium nitrate, potassium nitrate, ammonium perchlorate, sodium bisulfate, calcium chloride, lead picrate, potassium permanganate, and copper sulphate. Furthermore, any suitable acid can be used with the present invention, either alone or in combination, including perchloric acid, acetic anhydride, adenosine triphosphate, maleic anhydride, picric acid, formic anhydride, benzoic anhydride, manganese heptoxide, and phthalic anhydride. In addition, any suitable abrasive can be used with the present invention, either alone or in combination, including boron carbide, calcite, ceramic aluminum oxide, staurolite, pumice, rouge, glass powder, silicon carbide, and borazon. With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention.
Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
This application claims the benefit of U.S. Provisional Patent Application No. 62/314,093 filed on Mar. 28, 2016, entitled “GAS PROPELLED MUNITIONS CLEANING SYSTEM (GPMCS),”and U.S. Provisional Patent Application No. 62/334,619 filed on May 11, 2016, entitled “GAS PROPELLED MUNITIONS ANTIFOULING SYSTEM (GPMAS),” which are hereby incorporated by reference in their entirety for all that is taught and disclosed therein.
Filing Document | Filing Date | Country | Kind |
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PCT/US2017/024470 | 3/28/2017 | WO | 00 |
Number | Date | Country | |
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62314093 | Mar 2016 | US | |
62334619 | May 2016 | US |