Patent Publication Number: US-2020278184-A1

Title: Cartridge For Rendering A Firearm Inoperative

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. provisional patent application Ser. No. 62/794,990, which was filed on Jan. 21, 2019, and entitled “Cartridge for Destroying a Firearm.” 
    
    
     TECHNICAL FIELD 
     The present invention relates to a cartridge for rendering a firearm unusable for its intended purpose. More specifically, a cartridge which will not discharge a projectile, but will instead weld itself in place within the chamber of the firearm when the trigger is pulled, is provided. 
     BACKGROUND INFORMATION 
     Military personnel sometimes acquire control of firearms that were previously used by their enemies, but which they cannot carry with them on their current mission. Reasons might include unnecessary and/or hindering bulk and weight. Leaving the gun behind and useable could result in its use by other enemy personnel. Rendering the gun useless for its intended purpose before leaving it behind is thus desirable. 
     Similarly, law enforcement personnel are sometimes required to destroy a firearm either by department policy or by a court order. A simple means of rendering the firearm useless for its intended purpose is therefore desirable. 
     The means of rendering the gun useless should not add significant weight or bulk to the total load that must be carried. A firearm cartridge is sufficiently small so that the burden of carrying a small number of special purpose cartridges is small. Accordingly, there is a need for a cartridge which, when placed in a firearm, renders that firearm useless when the trigger is pulled. 
     SUMMARY 
     The above needs are met by a cartridge for rendering a firearm inoperative. The cartridge comprises a thermite charge having a first end and a second end, a primer secured at the first end, and a bullet secured to the second end. The bullet is made from thermite. 
     The above needs are further met by a method of rendering a firearm inoperative. The method comprises providing a cartridge. The cartridge comprises a thermite charge having a first end and a second end, a primer secured at the first end, and a bullet secured to the second end. The bullet is made from thermite. The cartridge is placed within a chamber of the firearm, and the trigger of the firearm is squeezed. 
     These and other aspects of the invention will become more apparent through the following description and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a cutaway side elevational view of a cartridge for destroying a firearm. 
         FIG. 2  is a cutaway side elevational view of another cartridge for destroying a firearm. 
         FIG. 3  is a cutaway side elevational view of yet another cartridge for destroying a firearm. 
     
    
    
     Like reference characters denote like elements throughout the drawing. 
     DETAILED DESCRIPTION 
     Referring to the drawings, a cartridge  10  for destroying a firearm is shown. As shown in  FIGS. 1-3 , the cartridge  10  resembles a standard cartridge for the firearm to be destroyed, but may include coloring or other visual indicia to clearly distinguish it from a conventional cartridge for the firearm. The illustrated example of the cartridge  10  includes a casing  12  having a primer pocket  14  with a primer  16  secured therein, although a caseless cartridge could be used without departing from the invention. The casing  12  includes an interior  18  having a thermite charge  20  disposed therein. A bullet  22  is secured to the casing  12  in a manner that will resist passage of the bullet through the barrel of the firearm when the cartridge  10  is activated, for example, using an adhesive such as epoxy. 
     Those skilled in the art of thermite will recognize that a typical thermite charge includes a metal oxide and a reducing metal. When heated to a sufficient temperature, the thermite is ignited, commencing an exothermic reaction between the metal oxide and reducing metal. Examples of metal oxides  34  include La 2 O 3 , AgO, ThO 2 , SrO, ZrO 2 , UO 2 , BaO, CeO 2 , B 2 O 3 , SiO 2 , V 2 O 5 , Ta 2 O 5 , NiO, Ni 2 O 3 , Cr 2 O 3 , MoO 3 , P 2 O 5 , SnO 2 , WO 2 , WO 3 , Fe 3 O 4 , COO, Co 3 O 4 , Sb 2 O 3 , PbO, Fe 2 O 3 , Bi 2 O 3 , MnO 2 , Cu 2 O, and CuO. Example reducing metals  36  include Al, Zr, Th, Ca, Mg, U, B, Ce, Be, Ti, Ta, Hf, and La. 
     One example utilizes cupric oxide (CuO) and aluminum. The resulting chemical reaction is 3CuO+2Al→ 3 Cu+Al 2 O 3 + heat. The reaction therefore requires 3 moles of CuO, weighing 79.5454 grams/mole, for every 2 moles of Al, weighing 26.98154 grams/mole. CuO has a density of 6.315 g/cm 3 , and aluminum has a density of 2.70 g/cm 3 . Therefore, the volume of CuO required for every 3 moles is 37.788 cm 3 . Similarly, the volume of Al required for every 2 moles is 19.986 cm 3 . 
     Another example utilizes iron oxide (Fe 2 O 3 ) and aluminum, which results in the reaction Fe 2 O 3 +2Al→2Fe+Al 2 O 3 . In this example, one mole of iron oxide is required for every two moles of aluminum. Fe 2 O 3  has a mass of 159.69 g/mol, so 159.69 g of iron oxide is required for every 53.96308 g. of aluminum (26.98154 grams/mole). The density of Fe 2 O 3  is 5.242 g/cm 3 , so 30.464 cm 3  of Fe 2 O 3  is required for every 15.989 cm3 of aluminum (2.70 g/cm 3 ). 
     Yet another example utilizes Iron and cupric oxide, which react according to Fe+CuO→FeO+Cu. In this example, a mole of iron has a mass of 55.845 g, and a density of 7.874 g/cm 3 . Therefore, 7.092 cm 3  of iron are needed to react with every 12.596 cm 3  of cupric oxide. If other metal oxides and reducing metals are selected, then the relative thickness of the metal oxide  12  and reducing metal  14  can be similarly determined. 
     A further possible combination utilizes Al as the reducing metal, and a combination of both CuO and Fe 2 O 3  as metal oxides. Depending on the proportions of CuO and Fe 2 O 3  to be utilized, the amounts of each of the metal oxides and the reducing metal can be calculated as described above. This combination provides an advantageous combination of easy ignitability and slow, low pressure once ignited. 
     The thermite can take any of numerous forms, including rods, pellets, powders, cold-pressed powders, hot pressed powders, or layered structures of alternating metal oxide and reducing metal. If the thermite is in the form of a single pellet rather than powdered or granular, then the primer  16  and bullet  22  may be seated within opposing ends of the thermite, eliminating the need for a casing  12 . 
     The bullet  22  is not a conventional bullet, and is not intended to be launched from the firearm. Instead, the bullet is also made from thermite, with the thermite combinations discussed above being possible combinations for the bullet  22 . The illustrated example of the bullet  22  is made by hot pressing the thermite into a cylindrical shape. The shape of the bullet  22  not only provides additional contact between the bullet  22  and the barrel of a firearm, but also provides an additional visual distinction between the cartridge  10  and conventional ammunition. Some examples of the bullet  22  may be made from slower burning thermites, which, with the bullet in direct contact with the barrel, are anticipated to penetrate the chrome lining on a chrome lined barrel, and to effectively weld the barrel shut. 
     The primer  16  may be a conventional primer, or may be a primer as disclosed in US 2016/0102030, which was invented by Kevin R. Coffey et al. and published on Apr. 14, 2016, the entire disclosure of which is expressly incorporated herein by reference. Alternatively, the primer may be of a type disclosed in US patent application Ser. No. 16/175,589, which was filed by Timothy Mohler et al. on Oct. 30, 2018, the entire disclosure of which is expressly incorporated herein by reference. Some examples of the primer  24  may include an aperture  26  ( FIG. 2 ) therein. As another alternative, an aperture  28  may be defined in the base  30  ( FIG. 3 ) of the casing  12 . 
     In use, the cartridge  10  is placed into the chamber of a firearm, and the trigger of the firearm is pulled, causing the firing pin to strike the primer  16 ,  24 , thereby igniting the thermite charge  20 . The bullet  22  is not intended to be fired from the gun, but to be ignited by the thermite charge  20 . As the thermite  20  within the cartridge  10  ignites, the cartridge  10  essentially welds itself to the firearm, perhaps at least partially melting and rendering useless components of the firearm in contact with or adjacent to the cartridge  10 . The bullet  22  welds itself to the barrel of the firearm. Combustion products pass through the aperture  26  or  28 , thus welding the firing pin and firing pin channel. The firearm, which may, for example, have been taken from an enemy during a military operation, is thus rendered useless. 
     The present invention thus provides a means of disabling and rendering useless a firearm that, for example, must be left behind during a military operation. The firearm disabling cartridge is easy to carry, and readily distinguishable from conventional ammunition. The firearm disabling cartridge can be used quickly and easily, ensuring that other enemies will not use the disabled firearm. 
     A variety of modifications to the above-described embodiments will be apparent to those skilled in the art from this disclosure. Thus, the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The particular embodiments disclosed are meant to be illustrative only and not limiting as to the scope of the invention. The appended claims, rather than to the foregoing specification, should be referenced to indicate the scope of the invention.