US20060283314A1 - Bismuth projectile - Google Patents

Bismuth projectile Download PDF

Info

Publication number
US20060283314A1
US20060283314A1 US11/346,077 US34607706A US2006283314A1 US 20060283314 A1 US20060283314 A1 US 20060283314A1 US 34607706 A US34607706 A US 34607706A US 2006283314 A1 US2006283314 A1 US 2006283314A1
Authority
US
United States
Prior art keywords
projectile
making
bismuth
molten
polymer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US11/346,077
Inventor
Anthony Cesaroni
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US11/346,077 priority Critical patent/US20060283314A1/en
Publication of US20060283314A1 publication Critical patent/US20060283314A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42BEXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B12/00Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material
    • F42B12/72Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the material
    • F42B12/74Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the material of the core or solid body
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42BEXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B30/00Projectiles or missiles, not otherwise provided for, characterised by the ammunition class or type, e.g. by the launching apparatus or weapon used
    • F42B30/02Bullets
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42BEXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B33/00Manufacture of ammunition; Dismantling of ammunition; Apparatus therefor

Definitions

  • the present invention relates to a bismuth projectile and a method of making a bismuth projectile.
  • Firearms are used in a wide variety of ways, including hunting and other sporting activities, law enforcement activities and military activities.
  • a “firearm” is intended to include rifles, pistols, guns and the like.
  • hunting activities spent bullets or parts of spent bullets remain in the environment. They may be eaten by game, or other animals or birds, either inadvertently or out of curiosity.
  • lead-containing bullets are a health hazard in that fumes of lead are dispersed into the atmosphere on impact of the bullet on the target or wood or other material behind the target.
  • the resultant haze is hazardous to the health of persons using the firing range, or employed in the firing range, and restrictions may be required on the amount of time that may be spent by a person at or on a firing range.
  • bullets may be collected from a firing range in order that the materials from which the bullets are formed may be recycled, fumes from lead-containing bullets are a major health hazard.
  • bullets In military activities, bullets must be capable of being used in rapid-firing firearms, without causing jamming of the firearm during use.
  • Bullets may be categorized as being frangible bullets or non-frangible bullets. The latter may substantially retain their shape on impact or become distorted in shape on impact without fragmentation. Frangible bullets are intended to break apart on impact.
  • Some firearms are reloaded by mechanical means, for instance the use of a bolt action to eject the shell of a spent bullet and insert a new bullet into the firing chamber of the firearm.
  • the weight of the bullet has little significant bearing on the reloading of the firearm.
  • other firearms are automatic firearms, in which case the firing of one bullet actuates mechanisms for ejection of the spent shell and insertion of the next bullet into the firing chamber, often in a very rapid manner.
  • Such mechanisms may, for instance, be actuated directly by pressure generated from the barrel or gas activated using gas obtained from the barrel.
  • the weight of the bullet must be sufficient to create a pressure within the barrel during the firing of the bullet that is sufficient to actuate the mechanisms for ejection of the shell and insertion of the next bullet into the firing chamber.
  • bullets intended for rapid-firing firearms must have properties that will withstand the temperatures to which the bullet might be subjected in the firing chamber, without softening of any casing, fragmentation of a non-frangible bullet or other deleterious effects that might cause malfinctioning of the firearm, poor trajectory of the bullet or other problems.
  • U.S. Pat. No. 5,399,187 is directed to a bullet formed from tungsten, or an alloy of tungsten, and phenol formaldehyde or polymethylmethacrylate polymers.
  • U.S. Pat. No. 5,012,743 is directed to a light weight elongated projectile formed from a casing of copper alloy, steel or similar material and a lower density core e.g. polycarbonate or polyamide.
  • International Patent Application No. WO 95/23952 is directed to a projectile having a core of polyethylene and iron.
  • German Patent No. 9209598 is directed to a bullet formed from a plastic viz. polypropylene homopolymer, and a metal jacket.
  • U.S. Pat. No. 6,257,149 is directed to an injection molded bullet having a polymer and polymer metal composite, wherein the metal is in a powdered form.
  • bismuth is typically alloyed with metals such as tin or zinc, for example.
  • metals such as tin or zinc, for example.
  • Tin and zinc have a specific gravity of 7.31 and 7.133, respectively, so the resulting bismuth/tin/zinc alloy will have a lower specific gravity than pure bismuth, thus producing a projectile with lower ballistic energy for a given velocity.
  • Other metals such as cadmium, for example, can be alloyed with bismuth but cadmium is known to be toxic.
  • Pure bismuth may be formed into a projectile by casting or spin molding, which can negatively affect ultimate material properties such as density and net shape in the finished article.
  • a method for making a projectile such as a bullet, from molten or partially molten bismuth.
  • the method comprises a projectile comprising injection molding a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer to form a projectile.
  • an injection molding method for making a projectile from a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer, whereby the bismuth expands when it solidifies, which substantially eliminates shrinkage, improves densification and bonding to a copper jacket or matrix, if employed.
  • a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer injection molded into the copper jacket or matrix also produces a frangible bullet that retains its barrel signature.
  • a method for the manufacture of a projectile comprising injecting molten or partially molten bismuth into a mold to form a projectile.
  • a method for making a projectile comprising:
  • a projectile comprising a composition comprising bismuth and a non-alloying metal and/or a polymer.
  • Injection molding is limited to specific types of materials due to temperatures, required injection rates, heat transfer issues, etc.
  • Bismuth has a relatively low melt temperature comparable to many polymers.
  • Bismuth has a relatively low specific heat compared to other metals (122 J/Kg ⁇ K) thus improving heat transfer issues in injection molding runner systems, etc.
  • Injection molding pressures are typically in the many thousands of pounds per square inch. This produces parts that can exhibit high density and detailed features using a high speed manufacturing process.
  • injection molding is intended to encompass molding processes such as, and without being limited thereto, conventional injection molding, thixotropic injection molding (TXM), high pressure die casting, and the like.
  • TXM thixotropic injection molding
  • Bismuth is considered to be non-toxic and is a good substitute for lead in projectiles used for firearms.
  • One embodiment of a method for making a lead-free projectile from molten or partially molten bismuth comprises injection molding of a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer to form a projectile. More particularly, the composition is injected into a mold to form a projectile.
  • partially molten is intended to encompass greater than about 0% molten to less than about 100% molten, typically, at least about 50% molten.
  • non-alloying metal is intended to encompass any metal or metal alloy that does not substantially alloy with bismuth; e.g. a low percentage of the metal or metal alloy may partially alloy (for example, about 1 to about 5%) with bismuth.
  • the non-alloying metal is any metal or metal alloy that has a higher melting point than bismuth, such as, and without being limited thereto, copper, tungsten, zirconium, steel, titanium, hafnium, niobium, tantalum, zinc, other high density metals and combinations thereof.
  • the properties or form of the metal or metal alloy will be such that the metal or metal alloy does not substantially alloy with bismuth.
  • zinc can alloy with bismuth if the zinc is in a molten state; however, if zinc is not in a molten state, it will not substantially alloy with bismuth and therefore, qualifies as a non-alloying metal, in this particular state, in accordance with the definition of non-alloying metal used herein.
  • the non-alloying metal(s) used herein are typically in solid form, such as, and without being limited thereto, powder or flake form but, it is understood that the non-alloying metal(s) can be in other forms as long as that form does not permit the metal to substantially alloy with bismuth during and/or after processing of the projectile.
  • Bismuth in a molten or partially molten form may act as a matrix or binder, if desired, with other non-alloying metal powder(s) that typically is any metal or metal alloy that has a higher melting point than bismuth, such as, and without being limited thereto, copper, tungsten, zirconium, steel, titanium, hafnium, niobium, tantalum, zinc, other high density metals and combinations thereof.
  • a slurry having molten or partially molten bismuth and a non-alloying metal powder, such as copper or tungsten are injected at temperatures typically from about 260° C. to about 375° C. to form a projectile.
  • the composition, in combination with the injection molding method, as described, can control both the mechanical properties and specific gravity of the article while allowing flexibility in raw material costs, depending on the application.
  • Bismuth in a molten or partially molten form may act as a matrix or binder, if desired, with other molten or partially molten polymer(s).
  • both the polymer(s) and bismuth are in a molten or partially molten state and are injected at temperatures typically from about 260° C. to about 375° C. to form a projectile.
  • the composition can impart desirable mechanical properties to the bismuth such as ductility, controlled frangibility, or ballistics, if desired.
  • the polymers can act as a lubricant to facilitate mold release and reduce vent and mold flash associated with low viscosity materials such as molten metals, including bismuth. Therefore, it would be beneficial to also combine molten or partially molten bismuth and a non-alloying metal(s) with polymer(s).
  • the temperatures used in the injection molding method of the present invention may be any suitable temperatures that permit bismuth to become molten or partially molten.
  • the suitable temperature is that which permits the polymer to become molten or partially molten and the bismuth to become molten or partially molten.
  • the suitable temperature is one that only permits the bismuth to become molten or partially molten.
  • Pre-compounding of the constituents can be accomplished by at least one of bulk mixing, mechanical compounding, compound extrusion, co-extrusion, co-injection, insert injection and transfer injection molding, to name a few.
  • compositions used herein may have more than one non-alloying metal and/or more than one polymer in combination with the molten or partially molten bismuth.
  • Another embodiment of the method for the manufacture of a projectile comprises inserting a jacket having one open end into a mold of a projectile.
  • a composition comprising molten or partially molten bismuth and, optionally, the non-alloying metal and/or the polymer are injected into the jacket through the open end and the projectile formed is removed from the mold.
  • Bismuth expands when it solidifies. This eliminates shrinkage, improves densification and bonding to the jacket.
  • the projectiles are manufactured in a one-step injection molding process.
  • a jacket in the form of a shell is inserted into a mold.
  • One end of the shell is open and the diameter of the shell is slightly less than the required diameter of the projectile; the mold is of a diameter slightly larger than the shell, to permit insertion of the shell into the mold, and of a diameter appropriate for production of projectiles of the required diameter.
  • the other end of the shell may be preformed into a desired shape e.g. a parabellum.
  • the shell can be any suitable shape for formation of at least a portion of the projectile.
  • the mold is a right cylindrical shell with an open end, the opposed end having rounded comers to facilitate forming into the desired shape in the mold.
  • the projectiles may be formed in at least two ways. For instance, if the projectile is a hollow tipped projectile or otherwise has a tip that is not formed from the shell, then the open end of the shell will be the tip of the projectile.
  • the rear of the projectile would normally be a truncated cone, or other suitable shape, and the mold would have a corresponding shape. If the projectile has a tip formed from the shell e.g. a rounded or parabolic tip, then the mold would have the corresponding shape.
  • the mold could be adapted to form at least two other shapes at the open end of the shell e.g. a core in the shape of a truncated cone extending from the shell or a right cylindrical shape.
  • the mold In the injection molding process, for a hollow point projectile, the mold is closed at which time the truncated cone, or other shape, end is formed.
  • the molten or partially molten bismuth and, optionally, the non-alloying metal and/or the polymer are injected, which forms the shape of the hollow point and also sizes the jacket to the size of the mold.
  • the projectile so formed is then ejected from the mold.
  • the tip be preformed but such preforming could be carried out in the mold prior to injection of the molten or partially molten bismuth.
  • the molten or partially molten bismuth is then injected and the open end formed into the desired shape.
  • the open end of the jacket is curled inwards towards the tip, and such curling is carried out by the closing of the mold, after injection of the polymer.
  • the inwardly curled end effectively locks the bismuth into the projectile.
  • the inwardly curled end prevents the bismuth from separating from the shell on firing of the projectile.
  • the jacket could be preformed i.e. formed prior to insertion into the mold of the injection molding process, or formed in the mold as part of the injection molding process.
  • the molten or partially molten bismuth used in the method of the present invention may also comprise the non-alloying metal and/or the polymer.
  • Some examples of compositions of the molten or partially molten bismuth includes from about 99% to about 100% by weight bismuth; a bismuth composition comprising molten or partially molten bismuth comprising from about 1% to about 99% by weight bismuth and from about 1% to about 99% by weight of a non-alloying metal, such as copper, tungsten, etc; a bismuth composition comprising molten or partially molten bismuth comprising from about 1% to about 99% by weight bismuth and from about 1% to about 99% by weight of a polymer; and a bismuth composition comprising molten or partially molten bismuth comprising from about 1% to about 99% by weight bismuth and from about 1% to about 99% by weight of both a non-alloying metal and a polymer combined.
  • the composition may contain any amount of bismuth, non-alloying metal and/or polymer depending on the properties of the projectile that are desired. For example, whether one desires a frangible bullet or a non-frangible bullet. In some instances, at least about 50% by weight bismuth is used. In more typical embodiments, the bismuth-containing projectiles contain at least about 60%, 70%, 80%, 90% or 95% by weight bismuth. Projectiles containing from about 60% to about 95% by weight or more bismuth perform well ballistically, and with increasingly high proportions of bismuth, such projectiles can approach or attain the ballistic performance of corresponding lead projectiles.
  • the bismuth composition comprises about 75% by weight bismuth and about 25% by weight copper. In another embodiment of a projectile, the bismuth composition comprises about 10% to about 15% by weight bismuth and about 85% to 90% by weight copper or steel.
  • the polymer used in the bismuth composition is typically amorphous or is of low crystallinity.
  • the polymer is both thermoplastic and thermoset polymers.
  • polymers such as ethylene/methacrylic acid copolymer ionomer, polyetherester elastomer, polydicyclopentadiene, polydimethylsiloxane, polyamide, and mixtures thereof.
  • a typical polymer is an ionomer. It is understood that the polymers would have a molecular weight suitable for the intended end-use and associated manufacturing processes.
  • ethylene/methacrylic acid copolymer ionomers are ethylene/methacrylic acid copolymers that have been partially neutralized with metal ions such as sodium or zinc. Such polymers are available from E.I. du Pont de Nemours and Company under the trademark Surlyn. It is preferred that the ionomer not be too viscous, for ease of dispersion of molten or partially molten bismuth in the composition.
  • polyamides include nylon 11, nylon 12, nylon 12/12 and related amorphous or low crystallinity polyamides. The polymer may also be a polyetherester elastomer e.g. an elastomer available from E. I. du Pont de Nemours and Company under the trademark Hytrel. Blends of such polymers or of such polymers with other polymers to provide amorphous or low crystallinity polymers may also be used.
  • the jacket may be formed from copper or nylon such as nylon 6-6, nylon 6-12, nylon 4-12, flexible nylon, nylon 6 or nylon 11, or nylon filled with impact modifiers.
  • flexible nylon refers to compositions of polyamides e.g. nylon 6-6, with copolymers of ethylene, e.g. copolymers of ethylene with methacrylic acid, which may be partially neutralized, and/or copolymers of ethylene with methacrylic esters and monomers copolymerizable therewith, such polymers being characterized by improved flexibility properties compared with the polyamide per se.
  • the jacket may also be formed from high molecular weight polyethylene, ultra high molecular weight polyethylene, polyetherester or other elastomers, polyphenylene sulphide, liquid crystal polymers (LCPs) and ionomers. It is also understood that the polyethylene used to manufacture the jacket may be a cross-linked polyethylene.
  • the jacket may be formed from a thermoplastic polymer
  • the jacket may be formed using an injection molding process. In doing so, care must be taken to ensure that the jacket is uniform in cross-section as any eccentricity in the jacket may affect the flight properties of the projectile after firing from the firearm. In particular, eccentricity may result in deviation of the projectile from its intended trajectory, resulting in a scatter of projectiles about the intended target.
  • the gate of the mold is along the axis of the projectile or jacket, to lessen the likelihood of shifting of the jacket in the mold during injection of the molten or partially molten bismuth.
  • Metals may be used to form the jacket, provided that the metals can be formed into the shape of the jacket to permit manufacture in a simple and consistent manner.
  • the jacket may have sufficient hardness so that the jacket does not abrade during passage down the barrel and result in contamination of the barrel.
  • the projectile is a frangible bullet then, typically, there is sufficient adhesion between the bismuth, optionally including a non-alloying metal and/or a polymer, and the jacket such that the bullet will retain its integrity from the moment of firing within the firearm until impact on the target.
  • the adhesion between the bismuth, optionally including a non-alloying metal and/or a polymer, and the jacket is, typically, not so strong as to inhibit fragmentation of the bullet on impact with the target, as this would affect the frangible properties of the bullet.
  • the jacket is typically formed of a material that will be marked during the firing of the bullet and the passage of the bullet down the barrel of the firearm, so that the signature of the firearm is imprinted on the jacket.
  • the jacket retains its integrity to a sufficient extent that the signature of the firearm is retained on the jacket even after impact of the bullet on a target.
  • the jacket may be constructed with internal serrations, such that on impact of the bullet with a target, the jacket will split along grooves of the serrations and assist in the frangible properties of the bullet. Such serrations will also assist in fragmentation of the bullet per se.
  • bismuth projectiles may be made using the method of the present invention.
  • a projectile of acceptable properties in particular, a projectile having the required weight characteristics for the particular firearm that is to be used, the bismuth and, optionally, other suitable materials such as the non-alloying metal and/or the polymer, and jackets may be used in any combination.
  • the injection molded bismuth projectiles of the present invention are particularly intended to replace conventional lead projectiles, or the equivalent thereof.
  • the projectiles would normally have a similar weight of a comparable lead projectile i.e. a lead projectile of the same dimensions.

Abstract

A bismuth projectile comprising bismuth and a non-alloying metal and/or a polymer. A method for making a projectile comprising injection molding molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer to form a projectile.

Description

    CROSS-REFERENCE TO RELATED APPLICATION
  • This application claims priority to copending U.S. provisional application entitled, “Bismuth Projectile,” having Ser. No. 60/648,704, filed Feb. 2, 2005, which is entirely incorporated herein by reference.
  • FIELD OF THE INVENTION
  • The present invention relates to a bismuth projectile and a method of making a bismuth projectile.
  • BACKGROUND OF THE INVENTION
  • Firearms are used in a wide variety of ways, including hunting and other sporting activities, law enforcement activities and military activities. As used herein, a “firearm” is intended to include rifles, pistols, guns and the like. In hunting activities, spent bullets or parts of spent bullets remain in the environment. They may be eaten by game, or other animals or birds, either inadvertently or out of curiosity.
  • This can cause poisoning effects, depending on the type of bullet. In addition, if the bullet is a frangible bullet, parts of the bullet will be scattered through the flesh of the game on impact, posing a potential danger to humans if the flesh is eaten or result in poisoning of the injured animal and the likelihood of a slow death. If the bullets contain lead, such poisoning and environmental effects pose significant concerns about health issues, and have resulted in governmental regulations banning the use of lead in such bullets.
  • In sporting activities and other testing of bullets e.g. in the firing of firearms at a firing range, lead-containing bullets are a health hazard in that fumes of lead are dispersed into the atmosphere on impact of the bullet on the target or wood or other material behind the target. The resultant haze is hazardous to the health of persons using the firing range, or employed in the firing range, and restrictions may be required on the amount of time that may be spent by a person at or on a firing range. Thus, even though bullets may be collected from a firing range in order that the materials from which the bullets are formed may be recycled, fumes from lead-containing bullets are a major health hazard.
  • In law enforcement activities, there is a need to be able to relate fragments of a bullet found at a crime scene to the firearm that was used to fire the bullet. Such a correlation is often important evidence in obtaining a conviction. The barrel of a firearm imparts markings to the outside of a bullet in the form of scratches, barrel rifling pattern or other marks, effectively a signature of the firearm. It is this signature that can be used in law enforcement to identify the firearm that was used to fire a particular bullet. However, to do so, it is essential that the bullet be capable of accepting and retaining such markings. This must occur even if the bullet is frangible, in which case law enforcement authorities must work with only particles or fragments of the bullet.
  • In military activities, bullets must be capable of being used in rapid-firing firearms, without causing jamming of the firearm during use.
  • Bullets may be categorized as being frangible bullets or non-frangible bullets. The latter may substantially retain their shape on impact or become distorted in shape on impact without fragmentation. Frangible bullets are intended to break apart on impact.
  • Some firearms are reloaded by mechanical means, for instance the use of a bolt action to eject the shell of a spent bullet and insert a new bullet into the firing chamber of the firearm. For firearms that are reloaded by such mechanical means, the weight of the bullet has little significant bearing on the reloading of the firearm. However, other firearms are automatic firearms, in which case the firing of one bullet actuates mechanisms for ejection of the spent shell and insertion of the next bullet into the firing chamber, often in a very rapid manner. Such mechanisms may, for instance, be actuated directly by pressure generated from the barrel or gas activated using gas obtained from the barrel. In both cases, the weight of the bullet must be sufficient to create a pressure within the barrel during the firing of the bullet that is sufficient to actuate the mechanisms for ejection of the shell and insertion of the next bullet into the firing chamber.
  • After the firing of a bullet in a firearm having an automatic reloading mechanism, the next round is inserted into the firing chamber pending the next firing of a further bullet. In rapid-firing firearms, the barrel of the firearm may become very hot, depending in particular on the number of bullets fired in a sequence, and consequently the bullet loaded into the firing chamber may become hot. Thus, bullets intended for rapid-firing firearms must have properties that will withstand the temperatures to which the bullet might be subjected in the firing chamber, without softening of any casing, fragmentation of a non-frangible bullet or other deleterious effects that might cause malfinctioning of the firearm, poor trajectory of the bullet or other problems.
  • Lead-free bullets are known. For instance, U.S. Pat. No. 5,399,187 is directed to a bullet formed from tungsten, or an alloy of tungsten, and phenol formaldehyde or polymethylmethacrylate polymers. U.S. Pat. No. 5,012,743 is directed to a light weight elongated projectile formed from a casing of copper alloy, steel or similar material and a lower density core e.g. polycarbonate or polyamide. International Patent Application No. WO 95/23952 is directed to a projectile having a core of polyethylene and iron. German Patent No. 9209598 is directed to a bullet formed from a plastic viz. polypropylene homopolymer, and a metal jacket. U.S. Pat. No. 4,503,777 is directed to a lead bullet manufactured by the pouring of lead. U.S. Pat. No. 6,257,149 is directed to an injection molded bullet having a polymer and polymer metal composite, wherein the metal is in a powdered form.
  • Projectiles formed from bismuth alloy powders are disclosed in International Patent Application Nos. WO 92/08097 and WO 95/08748. Bismuth is considered to be non-toxic and has a specific gravity of 9.747. However, elemental bismuth is highly crystalline in its solid form and, as such, limits the methods that can be used to process it. Methods typically employed in traditional bullet manufacturing where more ductile materials, such as lead, are used will cause bismuth to fracture. Methods such as punching, pressing and swaging, to name a few, will cause bismuth to fracture during production, thus destroying the projectile's structural properties. In order to improve the process ability of bismuth, bismuth is typically alloyed with metals such as tin or zinc, for example. Tin and zinc have a specific gravity of 7.31 and 7.133, respectively, so the resulting bismuth/tin/zinc alloy will have a lower specific gravity than pure bismuth, thus producing a projectile with lower ballistic energy for a given velocity. Other metals such as cadmium, for example, can be alloyed with bismuth but cadmium is known to be toxic.
  • Pure bismuth may be formed into a projectile by casting or spin molding, which can negatively affect ultimate material properties such as density and net shape in the finished article.
  • Thus, there is a need for a method for making a projectile from bismuth that obviates or mitigates at least some of the shortcomings of the methods of the prior art.
  • SUMMARY OF THE INVENTION
  • In one aspect, there is provided a method for making a projectile, such as a bullet, from molten or partially molten bismuth. The method comprises a projectile comprising injection molding a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer to form a projectile.
  • In a further aspect, there is provided an injection molding method for making a projectile from a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer, whereby the bismuth expands when it solidifies, which substantially eliminates shrinkage, improves densification and bonding to a copper jacket or matrix, if employed. In yet another aspect, there is provided a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer injection molded into the copper jacket or matrix also produces a frangible bullet that retains its barrel signature.
  • In another aspect, there is provided a method for the manufacture of a projectile comprising injecting molten or partially molten bismuth into a mold to form a projectile.
  • In a further aspect, there is provided a method for making a projectile comprising:
  • inserting a jacket having one open end into a mold of a projectile;
  • injecting a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer into the jacket through the open end; and
  • removing the projectile so formed from the mold.
  • In a further aspect, there is provided a projectile comprising a composition comprising bismuth and a non-alloying metal and/or a polymer.
  • In another aspect, there is provided a projectile made in accordance with any method discussed herein.
  • DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS
  • Injection molding is limited to specific types of materials due to temperatures, required injection rates, heat transfer issues, etc. Bismuth has a relatively low melt temperature comparable to many polymers. Bismuth has a relatively low specific heat compared to other metals (122 J/Kg·K) thus improving heat transfer issues in injection molding runner systems, etc. Injection molding pressures are typically in the many thousands of pounds per square inch. This produces parts that can exhibit high density and detailed features using a high speed manufacturing process.
  • As used herein, “injection molding” is intended to encompass molding processes such as, and without being limited thereto, conventional injection molding, thixotropic injection molding (TXM), high pressure die casting, and the like.
  • Bismuth is considered to be non-toxic and is a good substitute for lead in projectiles used for firearms. One embodiment of a method for making a lead-free projectile from molten or partially molten bismuth comprises injection molding of a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer to form a projectile. More particularly, the composition is injected into a mold to form a projectile.
  • As used herein, “partially molten” is intended to encompass greater than about 0% molten to less than about 100% molten, typically, at least about 50% molten.
  • As used herein “non-alloying metal” is intended to encompass any metal or metal alloy that does not substantially alloy with bismuth; e.g. a low percentage of the metal or metal alloy may partially alloy (for example, about 1 to about 5%) with bismuth. Typically, the non-alloying metal is any metal or metal alloy that has a higher melting point than bismuth, such as, and without being limited thereto, copper, tungsten, zirconium, steel, titanium, hafnium, niobium, tantalum, zinc, other high density metals and combinations thereof. The properties or form of the metal or metal alloy will be such that the metal or metal alloy does not substantially alloy with bismuth. For example, zinc can alloy with bismuth if the zinc is in a molten state; however, if zinc is not in a molten state, it will not substantially alloy with bismuth and therefore, qualifies as a non-alloying metal, in this particular state, in accordance with the definition of non-alloying metal used herein. The non-alloying metal(s) used herein are typically in solid form, such as, and without being limited thereto, powder or flake form but, it is understood that the non-alloying metal(s) can be in other forms as long as that form does not permit the metal to substantially alloy with bismuth during and/or after processing of the projectile.
  • Bismuth in a molten or partially molten form may act as a matrix or binder, if desired, with other non-alloying metal powder(s) that typically is any metal or metal alloy that has a higher melting point than bismuth, such as, and without being limited thereto, copper, tungsten, zirconium, steel, titanium, hafnium, niobium, tantalum, zinc, other high density metals and combinations thereof. In an example, during the injection molding method, a slurry having molten or partially molten bismuth and a non-alloying metal powder, such as copper or tungsten, are injected at temperatures typically from about 260° C. to about 375° C. to form a projectile. The composition, in combination with the injection molding method, as described, can control both the mechanical properties and specific gravity of the article while allowing flexibility in raw material costs, depending on the application.
  • Bismuth in a molten or partially molten form may act as a matrix or binder, if desired, with other molten or partially molten polymer(s). For example, during the injection molding method, both the polymer(s) and bismuth are in a molten or partially molten state and are injected at temperatures typically from about 260° C. to about 375° C. to form a projectile. The composition can impart desirable mechanical properties to the bismuth such as ductility, controlled frangibility, or ballistics, if desired. In addition, the polymers can act as a lubricant to facilitate mold release and reduce vent and mold flash associated with low viscosity materials such as molten metals, including bismuth. Therefore, it would be beneficial to also combine molten or partially molten bismuth and a non-alloying metal(s) with polymer(s).
  • The temperatures used in the injection molding method of the present invention may be any suitable temperatures that permit bismuth to become molten or partially molten. In one embodiment of the bismuth/polymer composition, the suitable temperature is that which permits the polymer to become molten or partially molten and the bismuth to become molten or partially molten. In a further embodiment of the bismuth composition comprising a non-alloying metal or a non-alloying metal and a polymer, the suitable temperature is one that only permits the bismuth to become molten or partially molten.
  • Pre-compounding of the constituents can be accomplished by at least one of bulk mixing, mechanical compounding, compound extrusion, co-extrusion, co-injection, insert injection and transfer injection molding, to name a few.
  • It is understood that the compositions used herein may have more than one non-alloying metal and/or more than one polymer in combination with the molten or partially molten bismuth.
  • Another embodiment of the method for the manufacture of a projectile comprises inserting a jacket having one open end into a mold of a projectile. A composition comprising molten or partially molten bismuth and, optionally, the non-alloying metal and/or the polymer are injected into the jacket through the open end and the projectile formed is removed from the mold. Bismuth expands when it solidifies. This eliminates shrinkage, improves densification and bonding to the jacket.
  • The separate components of the composition can be injected separately or in combination. In a typical embodiment of the present invention, the projectiles are manufactured in a one-step injection molding process. In such a process, a jacket in the form of a shell is inserted into a mold. One end of the shell is open and the diameter of the shell is slightly less than the required diameter of the projectile; the mold is of a diameter slightly larger than the shell, to permit insertion of the shell into the mold, and of a diameter appropriate for production of projectiles of the required diameter. The other end of the shell may be preformed into a desired shape e.g. a parabellum. However, in embodiments the shell can be any suitable shape for formation of at least a portion of the projectile. Typically, the mold is a right cylindrical shell with an open end, the opposed end having rounded comers to facilitate forming into the desired shape in the mold.
  • The projectiles may be formed in at least two ways. For instance, if the projectile is a hollow tipped projectile or otherwise has a tip that is not formed from the shell, then the open end of the shell will be the tip of the projectile. The rear of the projectile would normally be a truncated cone, or other suitable shape, and the mold would have a corresponding shape. If the projectile has a tip formed from the shell e.g. a rounded or parabolic tip, then the mold would have the corresponding shape. The mold could be adapted to form at least two other shapes at the open end of the shell e.g. a core in the shape of a truncated cone extending from the shell or a right cylindrical shape. In the injection molding process, for a hollow point projectile, the mold is closed at which time the truncated cone, or other shape, end is formed. The molten or partially molten bismuth and, optionally, the non-alloying metal and/or the polymer are injected, which forms the shape of the hollow point and also sizes the jacket to the size of the mold. The projectile so formed is then ejected from the mold.
  • In the injection molding process for a projectile with a solid point (tip), it is typical that the tip be preformed but such preforming could be carried out in the mold prior to injection of the molten or partially molten bismuth. The molten or partially molten bismuth is then injected and the open end formed into the desired shape. Typically, the open end of the jacket is curled inwards towards the tip, and such curling is carried out by the closing of the mold, after injection of the polymer. The inwardly curled end effectively locks the bismuth into the projectile. In particular, the inwardly curled end prevents the bismuth from separating from the shell on firing of the projectile.
  • It is understood that the jacket could be preformed i.e. formed prior to insertion into the mold of the injection molding process, or formed in the mold as part of the injection molding process.
  • The molten or partially molten bismuth used in the method of the present invention, as mentioned above, may also comprise the non-alloying metal and/or the polymer. Some examples of compositions of the molten or partially molten bismuth includes from about 99% to about 100% by weight bismuth; a bismuth composition comprising molten or partially molten bismuth comprising from about 1% to about 99% by weight bismuth and from about 1% to about 99% by weight of a non-alloying metal, such as copper, tungsten, etc; a bismuth composition comprising molten or partially molten bismuth comprising from about 1% to about 99% by weight bismuth and from about 1% to about 99% by weight of a polymer; and a bismuth composition comprising molten or partially molten bismuth comprising from about 1% to about 99% by weight bismuth and from about 1% to about 99% by weight of both a non-alloying metal and a polymer combined.
  • The composition may contain any amount of bismuth, non-alloying metal and/or polymer depending on the properties of the projectile that are desired. For example, whether one desires a frangible bullet or a non-frangible bullet. In some instances, at least about 50% by weight bismuth is used. In more typical embodiments, the bismuth-containing projectiles contain at least about 60%, 70%, 80%, 90% or 95% by weight bismuth. Projectiles containing from about 60% to about 95% by weight or more bismuth perform well ballistically, and with increasingly high proportions of bismuth, such projectiles can approach or attain the ballistic performance of corresponding lead projectiles. In a specific embodiment for a frangible projectile, the bismuth composition comprises about 75% by weight bismuth and about 25% by weight copper. In another embodiment of a projectile, the bismuth composition comprises about 10% to about 15% by weight bismuth and about 85% to 90% by weight copper or steel.
  • The polymer used in the bismuth composition is typically amorphous or is of low crystallinity. In embodiments, the polymer is both thermoplastic and thermoset polymers. For example, polymers such as ethylene/methacrylic acid copolymer ionomer, polyetherester elastomer, polydicyclopentadiene, polydimethylsiloxane, polyamide, and mixtures thereof. A typical polymer is an ionomer. It is understood that the polymers would have a molecular weight suitable for the intended end-use and associated manufacturing processes.
  • Examples of ethylene/methacrylic acid copolymer ionomers are ethylene/methacrylic acid copolymers that have been partially neutralized with metal ions such as sodium or zinc. Such polymers are available from E.I. du Pont de Nemours and Company under the trademark Surlyn. It is preferred that the ionomer not be too viscous, for ease of dispersion of molten or partially molten bismuth in the composition. Examples of polyamides include nylon 11, nylon 12, nylon 12/12 and related amorphous or low crystallinity polyamides. The polymer may also be a polyetherester elastomer e.g. an elastomer available from E. I. du Pont de Nemours and Company under the trademark Hytrel. Blends of such polymers or of such polymers with other polymers to provide amorphous or low crystallinity polymers may also be used.
  • If a jacket of a projectile is employed, a variety of materials may be used to form the jacket. For instance, the jacket may be formed from copper or nylon such as nylon 6-6, nylon 6-12, nylon 4-12, flexible nylon, nylon 6 or nylon 11, or nylon filled with impact modifiers. As used herein, flexible nylon refers to compositions of polyamides e.g. nylon 6-6, with copolymers of ethylene, e.g. copolymers of ethylene with methacrylic acid, which may be partially neutralized, and/or copolymers of ethylene with methacrylic esters and monomers copolymerizable therewith, such polymers being characterized by improved flexibility properties compared with the polyamide per se. The jacket may also be formed from high molecular weight polyethylene, ultra high molecular weight polyethylene, polyetherester or other elastomers, polyphenylene sulphide, liquid crystal polymers (LCPs) and ionomers. It is also understood that the polyethylene used to manufacture the jacket may be a cross-linked polyethylene.
  • If the jacket is formed from a thermoplastic polymer, the jacket may be formed using an injection molding process. In doing so, care must be taken to ensure that the jacket is uniform in cross-section as any eccentricity in the jacket may affect the flight properties of the projectile after firing from the firearm. In particular, eccentricity may result in deviation of the projectile from its intended trajectory, resulting in a scatter of projectiles about the intended target. Thus, typically, the gate of the mold is along the axis of the projectile or jacket, to lessen the likelihood of shifting of the jacket in the mold during injection of the molten or partially molten bismuth.
  • Metals may be used to form the jacket, provided that the metals can be formed into the shape of the jacket to permit manufacture in a simple and consistent manner. In addition, the jacket may have sufficient hardness so that the jacket does not abrade during passage down the barrel and result in contamination of the barrel.
  • If the projectile is a frangible bullet then, typically, there is sufficient adhesion between the bismuth, optionally including a non-alloying metal and/or a polymer, and the jacket such that the bullet will retain its integrity from the moment of firing within the firearm until impact on the target. However, the adhesion between the bismuth, optionally including a non-alloying metal and/or a polymer, and the jacket is, typically, not so strong as to inhibit fragmentation of the bullet on impact with the target, as this would affect the frangible properties of the bullet. The jacket is typically formed of a material that will be marked during the firing of the bullet and the passage of the bullet down the barrel of the firearm, so that the signature of the firearm is imprinted on the jacket. Moreover, typically, the jacket retains its integrity to a sufficient extent that the signature of the firearm is retained on the jacket even after impact of the bullet on a target.
  • The jacket may be constructed with internal serrations, such that on impact of the bullet with a target, the jacket will split along grooves of the serrations and assist in the frangible properties of the bullet. Such serrations will also assist in fragmentation of the bullet per se.
  • Various sizes and shapes of bismuth projectiles may be made using the method of the present invention. Within the requirements to manufacture a projectile of acceptable properties, in particular, a projectile having the required weight characteristics for the particular firearm that is to be used, the bismuth and, optionally, other suitable materials such as the non-alloying metal and/or the polymer, and jackets may be used in any combination.
  • The injection molded bismuth projectiles of the present invention are particularly intended to replace conventional lead projectiles, or the equivalent thereof. Thus, the projectiles would normally have a similar weight of a comparable lead projectile i.e. a lead projectile of the same dimensions.
  • The terms “a” and “an” as used herein are intended to encompass one or more.
  • The embodiments and examples set forth herein are presented to best explain the present invention and its practical application and to thereby enable those skilled in the art to make and utilize the invention. Those skilled in the art, however, will recognize that the description and examples are presented for the purpose of illustration and example only. Other variations and modifications of the present invention will be apparent to those of skill in the art, and it is the intent of the appended claims that such variations and modifications be covered.

Claims (40)

1. A method for making a projectile comprising injection molding a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer to form a projectile.
2. A method for making a projectile of claim 1, wherein the projectile is a bullet.
3. A method for making a projectile of claim 1, wherein the projectile is a high density projectile.
4. A method for making a projectile of claim 1, wherein injection molding comprises injecting the composition into a mold to form the projectile.
5. A method for making a projectile of claim 1, wherein injection molding is conventional injection molding, thixotropic injection molding (TXM), and/or high pressure die casting.
6. A method for making a projectile of claim 1, wherein partially molten is at least about 50% molten.
7. A method for making a projectile of claim 1, wherein the composition comprises the molten or partially molten bismuth and the non-alloying metal and/or the polymer.
8. A method for making a projectile of claim 1, wherein the composition comprises the molten or partially molten bismuth, the non-alloying metal and the polymer.
9. A method for making a projectile of claim 1, wherein the non-alloying metal is selected from the group consisting of copper, tungsten, zirconium, steel, titanium, hafnium, niobium, tantalum, zinc, other high density metals and combinations thereof.
10. A method for making a projectile of claim 1, wherein the injection molding is at any suitable temperature that permits bismuth to become molten or partially molten.
11. A method for making a projectile of claim 10, wherein the injection molding is conducted at a temperature from about 260° C. to about 375° C.
12. A method for making a projectile of claim 1, wherein the composition comprises from about 1% to about 99% by weight bismuth.
13. A method for making a projectile of claim 1, wherein the composition comprises from about 60% to about 95% by weight bismuth.
14. A method for making a projectile of claim 12, wherein the composition comprises from about 1% to about 99% by weight of the non-alloying metal and/or the polymer.
15. A method for making a projectile of claim 1, wherein the polymer is amorphous or has a low crystallinity.
16. A method for making a projectile of claim 1, wherein the polymer is selected from the group consisting of ethylene/methacrylic acid copolymer ionomer, polyetherester elastomer, polydicyclopentadiene, polydimethylsiloxane, polyamide, and mixtures thereof.
17. A method for making a projectile of claim 1, wherein the polymer is an ionomer.
18. A method for making a projectile comprising:
inserting a jacket having one open end into a mold of a projectile; injecting a composition comprising molten or partially molten bismuth and, optionally, a non-alloying metal and/or a polymer into the jacket through the open end; and
removing the projectile so formed from the mold.
19. A method for making a projectile of claim 18, wherein the projectile is a bullet.
20. A method for making a projectile of claim 18, wherein partially molten is at least about 50% molten.
21. A method for making a projectile of claim 18, wherein the composition comprises the molten or partially molten bismuth and the non-alloying metal and/or the polymer.
22. A method for making a projectile of claim 18, wherein the composition comprises the molten or partially molten bismuth, the non-alloying metal and the polymer.
23. A method for making a projectile of claim 18, wherein the non-alloying metal is selected from the group consisting of copper, tungsten, zirconium, steel, titanium, hafnium, niobium, tantalum, zinc, other high density metals and combinations thereof.
24. A method for making a projectile of claim 18, wherein the injecting the composition is at any suitable temperature that permits bismuth to become molten or partially molten.
25. A method for making a projectile of claim 18, wherein the composition comprises from about 1% to about 99% by weight bismuth.
26. A method for making a projectile of claim 18, wherein the composition comprises from about 60% to about 95% by weight bismuth.
27. A method for making a projectile of claim 25, wherein the composition comprises from about 1% to about 99% by weight of the non-alloying metal and/or the polymer.
28. A method for making a projectile of claim 18, wherein the polymer is amorphous or has a low crystallinity.
29. A method for making a projectile of claim 18, wherein the jacket comprises a metal.
30. A projectile made by the method of claim 1.
31. A projectile made by the method of claim 18.
32. A projectile comprising a composition comprising bismuth and a non-alloying metal and/or a polymer.
33. A projectile of claim 32, wherein the projectile is a bullet.
34. A projectile of claim 32, wherein the projectile is a high density projectile.
35. A projectile of claim 32, wherein the non-alloying metal is selected from the group consisting of copper, tungsten, zirconium, steel, titanium, hafnium, niobium, tantalum, zinc, other high density metals and combinations thereof.
36. A projectile of claim 32, wherein the composition comprises from about 1% to about 99% by weight bismuth.
37. A projectile of claim 32, wherein the composition comprises from about 60% to about 95% by weight bismuth.
38. A projectile of claim 32, wherein the composition comprises from about 1% to about 99% by weight of the non-alloying metal and/or the polymer.
39. A projectile of claim 32, wherein the polymer is amorphous or has a low crystallinity.
40. A projectile of claim 32, wherein the polymer is an ionomer.
US11/346,077 2005-02-02 2006-02-02 Bismuth projectile Abandoned US20060283314A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US11/346,077 US20060283314A1 (en) 2005-02-02 2006-02-02 Bismuth projectile

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US64870405P 2005-02-02 2005-02-02
US11/346,077 US20060283314A1 (en) 2005-02-02 2006-02-02 Bismuth projectile

Publications (1)

Publication Number Publication Date
US20060283314A1 true US20060283314A1 (en) 2006-12-21

Family

ID=36764143

Family Applications (1)

Application Number Title Priority Date Filing Date
US11/346,077 Abandoned US20060283314A1 (en) 2005-02-02 2006-02-02 Bismuth projectile

Country Status (2)

Country Link
US (1) US20060283314A1 (en)
CA (1) CA2535164A1 (en)

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080021159A1 (en) * 2006-07-21 2008-01-24 Tonson Abraham Thermoplastic vulcanizates having improved adhesion to polar substrates
CN101724285B (en) * 2008-10-14 2013-03-13 通用汽车环球科技运作公司 Molded or extruded combinations of light metal alloys and high-temperature polymers
US9157713B1 (en) 2013-03-15 2015-10-13 Vista Outdoor Operations Llc Limited range rifle projectile
US9170080B2 (en) 2013-03-15 2015-10-27 Alliant Techsystems Inc. Reloading kit with lead free bullet composition
US9506735B1 (en) 2016-03-09 2016-11-29 True Velocity, Inc. Method of making polymer ammunition cartridges having a two-piece primer insert
US9513096B2 (en) 2010-11-10 2016-12-06 True Velocity, Inc. Method of making a polymer ammunition cartridge casing
US9518810B1 (en) 2016-03-09 2016-12-13 True Velocity, Inc. Polymer ammunition cartridge having a two-piece primer insert
US9523563B1 (en) 2016-03-09 2016-12-20 True Velocity, Inc. Method of making ammunition having a two-piece primer insert
US9551557B1 (en) 2016-03-09 2017-01-24 True Velocity, Inc. Polymer ammunition having a two-piece primer insert
US9587918B1 (en) * 2015-09-24 2017-03-07 True Velocity, Inc. Ammunition having a projectile made by metal injection molding
CZ306552B6 (en) * 2013-11-19 2017-03-08 SVĂšM a.s. A bullet of the frangible type and a method of its production
US9835423B2 (en) 2010-11-10 2017-12-05 True Velocity, Inc. Polymer ammunition having a wicking texturing
US10041770B2 (en) 2010-11-10 2018-08-07 True Velocity, Inc. Metal injection molded ammunition cartridge
US10048049B2 (en) 2010-11-10 2018-08-14 True Velocity, Inc. Lightweight polymer ammunition cartridge having a primer diffuser
US10048052B2 (en) 2010-11-10 2018-08-14 True Velocity, Inc. Method of making a polymeric subsonic ammunition cartridge
US10081057B2 (en) 2010-11-10 2018-09-25 True Velocity, Inc. Method of making a projectile by metal injection molding
US10190857B2 (en) 2010-11-10 2019-01-29 True Velocity Ip Holdings, Llc Method of making polymeric subsonic ammunition
USD861118S1 (en) 2011-11-09 2019-09-24 True Velocity Ip Holdings, Llc Primer insert
US10429156B2 (en) 2010-11-10 2019-10-01 True Velocity Ip Holdings, Llc Subsonic polymeric ammunition cartridge
US10480915B2 (en) 2010-11-10 2019-11-19 True Velocity Ip Holdings, Llc Method of making a polymeric subsonic ammunition cartridge
US10591260B2 (en) 2010-11-10 2020-03-17 True Velocity Ip Holdings, Llc Polymer ammunition having a projectile made by metal injection molding
US10690464B2 (en) 2017-04-28 2020-06-23 Vista Outdoor Operations Llc Cartridge with combined effects projectile
US10760882B1 (en) 2017-08-08 2020-09-01 True Velocity Ip Holdings, Llc Metal injection molded ammunition cartridge
US10876822B2 (en) 2017-11-09 2020-12-29 True Velocity Ip Holdings, Llc Multi-piece polymer ammunition cartridge
WO2021046639A1 (en) * 2019-09-10 2021-03-18 Global Metallix Canada Inc. A thermoset-based frangible projectile
US11118875B1 (en) 2010-11-10 2021-09-14 True Velocity Ip Holdings, Llc Color coded polymer ammunition cartridge
WO2021263093A1 (en) * 2020-06-25 2021-12-30 Federal Cartridge Company Bismuth-based firearm projectiles, firearm cartridges including the same, and related methods
US11340050B2 (en) 2010-11-10 2022-05-24 True Velocity Ip Holdings, Llc Subsonic polymeric ammunition cartridge

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4503777A (en) * 1981-10-30 1985-03-12 Russell Young Semi-jacketed bullet having integral jacket retaining means, and method of making
US4517898A (en) * 1979-12-14 1985-05-21 Davis Dale M Highly accurate projectile for use with small arms
US4607573A (en) * 1984-04-03 1986-08-26 Ensign-Bickford Industries, Inc. Laminated fuse and manufacturing process therefor
US5012743A (en) * 1988-12-05 1991-05-07 Fabrique National Herstal, En Abrege Fn, Societe Anonyme High-performance projectile
US5399187A (en) * 1993-09-23 1995-03-21 Olin Corporation Lead-free bullett
US5496918A (en) * 1991-09-23 1996-03-05 Alliedsignal Inc. Process for improving the properties of polymers
US5513689A (en) * 1995-02-14 1996-05-07 Bismuth Cartridge, L.L.C. Method of manufacturing bismuth shot
US5540749A (en) * 1994-09-08 1996-07-30 Asarco Incorporated Production of spherical bismuth shot
US5597973A (en) * 1995-01-30 1997-01-28 The Ensign-Bickford Company Signal transmission fuse
US5616642A (en) * 1995-04-14 1997-04-01 West; Harley L. Lead-free frangible ammunition
US5730664A (en) * 1995-10-11 1998-03-24 Sumitomo Rubber Industries, Ltd. Solid golf ball
US5747722A (en) * 1996-01-11 1998-05-05 The Ensign-Bickford Company Detonators having multiple-line input leads
US5837924A (en) * 1995-11-21 1998-11-17 The Ensign-Bickford Company Signal transmission tube using reclaim material and method of manufacture
US6257149B1 (en) * 1996-04-03 2001-07-10 Cesaroni Technology, Inc. Lead-free bullet
US20060042456A1 (en) * 2002-08-16 2006-03-02 Bismuth Cartridge Company Method of making a frangible non-toxic projectile
US20070000404A1 (en) * 2004-04-26 2007-01-04 Olin Corporation, A Corporation Of The Commonwealth Of Virginia Jacketed boat-tail bullet

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4517898A (en) * 1979-12-14 1985-05-21 Davis Dale M Highly accurate projectile for use with small arms
US4503777A (en) * 1981-10-30 1985-03-12 Russell Young Semi-jacketed bullet having integral jacket retaining means, and method of making
US4607573A (en) * 1984-04-03 1986-08-26 Ensign-Bickford Industries, Inc. Laminated fuse and manufacturing process therefor
US5012743A (en) * 1988-12-05 1991-05-07 Fabrique National Herstal, En Abrege Fn, Societe Anonyme High-performance projectile
US5496918A (en) * 1991-09-23 1996-03-05 Alliedsignal Inc. Process for improving the properties of polymers
US5399187A (en) * 1993-09-23 1995-03-21 Olin Corporation Lead-free bullett
US5540749A (en) * 1994-09-08 1996-07-30 Asarco Incorporated Production of spherical bismuth shot
US5597973A (en) * 1995-01-30 1997-01-28 The Ensign-Bickford Company Signal transmission fuse
US5513689A (en) * 1995-02-14 1996-05-07 Bismuth Cartridge, L.L.C. Method of manufacturing bismuth shot
US5616642A (en) * 1995-04-14 1997-04-01 West; Harley L. Lead-free frangible ammunition
US5730664A (en) * 1995-10-11 1998-03-24 Sumitomo Rubber Industries, Ltd. Solid golf ball
US5837924A (en) * 1995-11-21 1998-11-17 The Ensign-Bickford Company Signal transmission tube using reclaim material and method of manufacture
US5747722A (en) * 1996-01-11 1998-05-05 The Ensign-Bickford Company Detonators having multiple-line input leads
US6257149B1 (en) * 1996-04-03 2001-07-10 Cesaroni Technology, Inc. Lead-free bullet
US20060042456A1 (en) * 2002-08-16 2006-03-02 Bismuth Cartridge Company Method of making a frangible non-toxic projectile
US20070000404A1 (en) * 2004-04-26 2007-01-04 Olin Corporation, A Corporation Of The Commonwealth Of Virginia Jacketed boat-tail bullet

Cited By (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080021159A1 (en) * 2006-07-21 2008-01-24 Tonson Abraham Thermoplastic vulcanizates having improved adhesion to polar substrates
US8071220B2 (en) * 2006-07-21 2011-12-06 Exxonmobil Chemical Patents Inc. Thermoplastic vulcanizates having improved adhesion to polar substrates
CN101724285B (en) * 2008-10-14 2013-03-13 通用汽车环球科技运作公司 Molded or extruded combinations of light metal alloys and high-temperature polymers
US10591260B2 (en) 2010-11-10 2020-03-17 True Velocity Ip Holdings, Llc Polymer ammunition having a projectile made by metal injection molding
US9513096B2 (en) 2010-11-10 2016-12-06 True Velocity, Inc. Method of making a polymer ammunition cartridge casing
US11340050B2 (en) 2010-11-10 2022-05-24 True Velocity Ip Holdings, Llc Subsonic polymeric ammunition cartridge
US10190857B2 (en) 2010-11-10 2019-01-29 True Velocity Ip Holdings, Llc Method of making polymeric subsonic ammunition
US11118875B1 (en) 2010-11-10 2021-09-14 True Velocity Ip Holdings, Llc Color coded polymer ammunition cartridge
US11092413B2 (en) 2010-11-10 2021-08-17 True Velocity Ip Holdings, Llc Metal injection molded primer insert for polymer ammunition
US9546849B2 (en) 2010-11-10 2017-01-17 True Velocity, Inc. Lightweight polymer ammunition cartridge casings
US11079209B2 (en) 2010-11-10 2021-08-03 True Velocity Ip Holdings, Llc Method of making polymer ammunition having a wicking texturing
US11047661B2 (en) 2010-11-10 2021-06-29 True Velocity Ip Holdings, Llc Method of making a metal primer insert by injection molding
US11047662B2 (en) 2010-11-10 2021-06-29 True Velocity Ip Holdings, Llc Method of making a polymer ammunition cartridge having a wicking texturing
US10480915B2 (en) 2010-11-10 2019-11-19 True Velocity Ip Holdings, Llc Method of making a polymeric subsonic ammunition cartridge
US9835423B2 (en) 2010-11-10 2017-12-05 True Velocity, Inc. Polymer ammunition having a wicking texturing
US10234253B2 (en) 2010-11-10 2019-03-19 True Velocity, Inc. Method of making a polymer ammunition cartridge having a metal injection molded primer insert
US9933241B2 (en) 2010-11-10 2018-04-03 True Velocity, Inc. Method of making a primer insert for use in polymer ammunition
US10041770B2 (en) 2010-11-10 2018-08-07 True Velocity, Inc. Metal injection molded ammunition cartridge
US10048049B2 (en) 2010-11-10 2018-08-14 True Velocity, Inc. Lightweight polymer ammunition cartridge having a primer diffuser
US10048052B2 (en) 2010-11-10 2018-08-14 True Velocity, Inc. Method of making a polymeric subsonic ammunition cartridge
US10429156B2 (en) 2010-11-10 2019-10-01 True Velocity Ip Holdings, Llc Subsonic polymeric ammunition cartridge
US10081057B2 (en) 2010-11-10 2018-09-25 True Velocity, Inc. Method of making a projectile by metal injection molding
US10145662B2 (en) 2010-11-10 2018-12-04 True Velocity Ip Holdings, Llc Method of making polymer ammunition having a metal injection molded primer insert
US9631907B2 (en) 2010-11-10 2017-04-25 True Velocity, Inc. Polymer ammunition cartridge having a wicking texturing
US10352670B2 (en) 2010-11-10 2019-07-16 True Velocity Ip Holdings, Llc Lightweight polymer ammunition cartridge casings
US9927219B2 (en) 2010-11-10 2018-03-27 True Velocity, Inc. Primer insert for a polymer ammunition cartridge casing
US10254096B2 (en) 2010-11-10 2019-04-09 True Velocity Ip Holdings, Llc Polymer ammunition having a MIM primer insert
USD861119S1 (en) 2011-11-09 2019-09-24 True Velocity Ip Holdings, Llc Ammunition cartridge
USD861118S1 (en) 2011-11-09 2019-09-24 True Velocity Ip Holdings, Llc Primer insert
USD828483S1 (en) 2011-11-09 2018-09-11 True Velocity Ip Holdings, Llc Cartridge base insert
USD836180S1 (en) 2011-11-09 2018-12-18 True Velocity Ip Holdings, Llc Ammunition cartridge with primer insert
USD849181S1 (en) 2011-11-09 2019-05-21 True Velocity Ip Holdings, Llc Cartridge primer insert
US9170080B2 (en) 2013-03-15 2015-10-27 Alliant Techsystems Inc. Reloading kit with lead free bullet composition
US9157713B1 (en) 2013-03-15 2015-10-13 Vista Outdoor Operations Llc Limited range rifle projectile
CZ306552B6 (en) * 2013-11-19 2017-03-08 SVĂšM a.s. A bullet of the frangible type and a method of its production
US9587918B1 (en) * 2015-09-24 2017-03-07 True Velocity, Inc. Ammunition having a projectile made by metal injection molding
US9551557B1 (en) 2016-03-09 2017-01-24 True Velocity, Inc. Polymer ammunition having a two-piece primer insert
US9523563B1 (en) 2016-03-09 2016-12-20 True Velocity, Inc. Method of making ammunition having a two-piece primer insert
US9518810B1 (en) 2016-03-09 2016-12-13 True Velocity, Inc. Polymer ammunition cartridge having a two-piece primer insert
US9506735B1 (en) 2016-03-09 2016-11-29 True Velocity, Inc. Method of making polymer ammunition cartridges having a two-piece primer insert
US10690464B2 (en) 2017-04-28 2020-06-23 Vista Outdoor Operations Llc Cartridge with combined effects projectile
US11226182B2 (en) 2017-04-28 2022-01-18 Vista Outdoor Operations Llc Cartridge with combined effects projectile
US10760882B1 (en) 2017-08-08 2020-09-01 True Velocity Ip Holdings, Llc Metal injection molded ammunition cartridge
US10876822B2 (en) 2017-11-09 2020-12-29 True Velocity Ip Holdings, Llc Multi-piece polymer ammunition cartridge
WO2021046639A1 (en) * 2019-09-10 2021-03-18 Global Metallix Canada Inc. A thermoset-based frangible projectile
US11852449B2 (en) 2020-06-25 2023-12-26 Federal Cartridge Company Bismuth-based firearm projectiles, firearm cartridges including the same, and related methods
WO2021263093A1 (en) * 2020-06-25 2021-12-30 Federal Cartridge Company Bismuth-based firearm projectiles, firearm cartridges including the same, and related methods

Also Published As

Publication number Publication date
CA2535164A1 (en) 2006-08-02

Similar Documents

Publication Publication Date Title
US20060283314A1 (en) Bismuth projectile
US6257149B1 (en) Lead-free bullet
US5763819A (en) Obstacle piercing frangible bullet
US5719352A (en) Low toxicity shot pellets
US7607394B2 (en) Lead-free projectiles
US6439124B1 (en) Lead-free tin projectile
AU754891B2 (en) Frangible powdered iron projectiles
US9212878B2 (en) Composite projectile and cartridge with composite projectile
JP3634367B2 (en) Lead free bullet
US7059233B2 (en) Tungsten-containing articles and methods for forming the same
US5665808A (en) Low toxicity composite bullet and material therefor
JP4744454B2 (en) One piece core ammunition with jacket
US7555987B2 (en) Frangible powered iron projectiles
WO2006031246A1 (en) Jacketed boat-tail bullet
US20050066850A1 (en) Non-lead composition and method of manufacturing non-lead projectiles and projectile cores therewith
WO2007022612A1 (en) Non-toxic jacketed ammunition
GB2372800A (en) Shotgun shot, pellets and bullets
CA2471537C (en) Non-lead composition and method of manufacturing non-lead projectiles and projectile cores therewith
CA2516893A1 (en) Non-toxic jacketed ammunition
CZ2010237A3 (en) Frangible-type projectile
KR20000070539A (en) Frangible powdered iron projectiles

Legal Events

Date Code Title Description
STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION