GB2211920A - Metal shot for sporting pellets - Google Patents

Metal shot for sporting pellets Download PDF

Info

Publication number
GB2211920A
GB2211920A GB8823798A GB8823798A GB2211920A GB 2211920 A GB2211920 A GB 2211920A GB 8823798 A GB8823798 A GB 8823798A GB 8823798 A GB8823798 A GB 8823798A GB 2211920 A GB2211920 A GB 2211920A
Authority
GB
United Kingdom
Prior art keywords
zinc
pellet
pellets
shot
tin
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.)
Granted
Application number
GB8823798A
Other versions
GB8823798D0 (en
GB2211920B (en
Inventor
Christopher William Haines
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.)
Am & S Europ
Original Assignee
Am & S Europ
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 Am & S Europ filed Critical Am & S Europ
Publication of GB8823798D0 publication Critical patent/GB8823798D0/en
Publication of GB2211920A publication Critical patent/GB2211920A/en
Application granted granted Critical
Publication of GB2211920B publication Critical patent/GB2211920B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/04Making non-ferrous alloys by powder metallurgy
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42BEXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B7/00Shotgun ammunition
    • F42B7/02Cartridges, i.e. cases with propellant charge and missile
    • F42B7/04Cartridges, i.e. cases with propellant charge and missile of pellet type
    • F42B7/046Pellets or shot therefor

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)

Abstract

Sporting shot-gun pellets of diameter 1.9 - 5.5mm and density 6.5-7.3, having no voids communicating with the outer surface, are formed from zinc or a zinc-based alloy. Preferred alloys are based on zinc/aluminium (3.5 - 6% Al) or zinc/tin (0.5 - 2% sn) with possible additions of copper, magnesium, silicon, an alkali metal or an alkaline earth metal. The pellets are made by vibrating drops of molten alloy through orifices into a bath of cooling fluid in which they encounter downwardly- inclined planes.

Description

Irlprovem.ents in or relating to metal shot and the production thereof This invention relates to metal shot, as used for game shooting and sporting purposes, e.g. in shot-gun cartridges.
There is increasing concern about the effects of lead and lead-based chemicals upon the environnent and particularly about the effects of lead and lead compounds on wildlife.
Recently legislation was introduced to phase out the use of lead in fishing weights and now attention has turned to the effects of lead pellets e.g. from shot-gun cartridges upon birds which feed on the ground and around fresh-water and sea-water areas.. It has been shown that birds can ingest lead pellets by ground feeding and that these pellets can lead in the long-term to lead poisoning in the species concerned. Particularly vulnerable are certain species of swans, geese and ducks. For exarple, it is estimated that, each year in Great Britain 8000 mallards die after ingesting lead gunshot (G.P.Fjudge 1983).
This invention seeks to ameloriate the problem of lead poisoning in wildlife by providing a safer alternative to traditional lead-shot and a cheaper alternative to the known mechanically-formed steel shot.
According to this invention we provide zinc or a zinc-based alloy which is formed into a substantially-spherical pellet having a diameter between 1.9 and 5.5 mm, and a density between 6.5 and 7.3 and without voids which communicate with the outer surface of the pellet.
Preferably the zinc based alloy is a zinc-aluminium or zinc-tin alloy with, optional additions of copper, magnesium, silicon, alkali metals, or alkaline earth metals.
There may be a small central cavity or micro-porosity within the spherical pellets due to the casting method of production, but the pellets should be substantially free from any voids which communicate with the outer surface of the pellet, and therefore will not affect ballistic properties. Typical porosity levels will be only of the order of 0.58 to 1.0E by volume.
The alloy fro which the pellets are produced should show a relatively low melting point and for this reason alloys based on Zn/3.5% aluminium to Zn/6% aluminium are preferred.
Alternatively, Zn/Sn alloys with a tin content of between 0.5 to 2.08 Sn may be used.
The zinc/aluminiunl alloys have the added advantage of low rates of corrosion attack on steel, when steel is used in the apparatus for producing the pellets.
It is desirable that the alloy used has a low specific heat, a low melting point and a low rate of attack on steel.
The pellets according to the invention are substantially spherical, free fror porosity and compare geometrically to current commercially- available lead shot.
Various methods of producing zinc based shot are technically possible, such as - die casting - ballheading/pressing fro wire/sheet - centrifugal casting of molten zinc or zinc based alloy However, these methods are believed to be somewhat expensive compared to methods which enable shot to be cast from molten zinc (or zinc based alloys) through a heated casting head such as an orificed plate or container into a bath of cooling fluid.
Shot sizes can be varied by altering the size of orifice in the casting head. the casting head can be fixed or can be vibrated to aid the formation of shot. The casting head can be between 1 and 50mr above the quenching medium but best results are obtained between 1.5me, and lOmm.
The quenching medium may be water based or oil based or a water/oil based combination can be used. Other additives such as surfactants, pH buffers and anti-corrosion chemicals can be used. It is advisable to minimize turbulence on the surface of the quenching medium to avoid shape variations.
Molten zinc and its alloys have a high heat content and thus require extended cooling periods which can be achieved by the use of deep quenching baths or inclined planes submerged below the coolant surface and careful control of coolant temperature. Casting temperature is dictated by factors such as size of shot, alloy used (which affects surface tension and viscosity) and the desire to minimise heat content.
Conveniently the pellets of the invention can be produced by means of a piece of proprietary equipment already known for making lead shot and known under the name BLEINEISTER (Manufactured by H. COLLIE GmbH of W.Germany). In this machine drops of molten alloy are vibrated through orifices into a bath of cooling fluid in which they encounter downwardly-inclined planes and roll down these planes. From the bottom end of the planes they fall more or less vertically through the fluid and reach the bottom of the fluid container solidified and substantially spherical in shape. Again, parameters such as diameter of orifice, slope of plane, and temperature of cooling fluid will have an effect on the size, and shape, of the product pellets, as will the composition of alloys being dispersed.
Suitable alloys for the production of shot according to this invention include zinc/aluminium (3.5-6.0%) and zinc/tin (0.5 to 2%) alloys; with or without the addition of the following additional alloying elements: (a) Copper 0.5 to 3.5% (b) Magnesium 0.01 to 2.5% (c) Lithium 0.001 to 0.5% (d) Silicon 0.001 to 1.0% (all percentage values being by weight) Examples of suitable alloys for shot forming are as follows:: EXAMPLE 1 3.8% - 4.5% Al 0.04% - 0.06% Mg + Zn + impurities EXAMPLE 2 3.8% - 4.5% Al 0.5% - 1.25% Cu 0.04% - 0.06% Mg + Zn + impurities EXAMPLE 3 3.8% - 4.5% Al 2.5% - 3.5% Cu 0.04% - 0.06 Mg + Zn + impurities EXAMPLE 4 3.8% - 4.5% Al 2.5% - 3.5% Cu 0.85% - 1.7% Mc + Zn + impurities EXAILE 5 3.8% - 4.5% Al 2.5% - 3.5% Cu 0.04% - 0.06% Mg 0.005% - 0.05% Li + Zn + impurities EXAMPLE 6 1.0 - 1.4 Sn 0.001 - 0.003 Li remainder Zn + impurities The reasons for deliberately adding various alloying elements to the Zn/Al - and Zn/Sn- based alloys for shot formation are as follows: I. For Zn/Al based alloys (a) Aluminium can be used to reduce melting point and thermal content of shot as well as to reduce attack on steel process machinery.
(b) Copper can be used to increase fluidity of molten metal which helps processing (particularly for smaller sizes). It also reduces porosity to minimal/negligable level.
(c) Magnesium can be used to decrease dendrite size and content in microstructure, thereby enhancing sphericity and also lowering (slightly) melting point.
(d) Lithium can be used to suppress dendritic growth and refines microstructure which enhances sphericity and surface finish.
(e) Silicon may be added to increase fluidity of molten metal thereby improving production of smaller shot by making the metal flow more freely through orifices in the production apparatus..
(f) Tin may be added in small quantities to improve size/weight distribution i.e. a larger proportion of shot is close to the mean size.
II. For Zn/Sn based alloys (a) Tin can be used to achieve product with minimal/negligable porosity and close size/weight distribution.
(b) Lithium can be used to enhance sphericity and good surface finish.

Claims (10)

CLAIMS:
1. A sporting pellet composed of zinc or a zinc-based alloy formed into substantially spherical form and having a diameter between 1.9 and 5.5 millimetres, a density between 6.5 and 7.3 and being without voids which communicate with the outer surface of the pellet.
2. A pellet as claimed in claim 1 which is based on a zinc/aluminium alloy or a zinc/tin alloy.
3. A pellet as claimed in claims 1 or 2 based on zinc/aluminium or zinc/tin which further contains an element selected fro aluminium, tin, copper, magnesium, silicon, an alkali metal or an alkaline earth metal.
4. A pellet as claimed in claim 3 wherein the alkali metal is lithium.
5. A pellet as claimed in any one of claims 1 to 4 which is cast from a zinc/aluminium alloy having a melting point no higher than 3900C.
6. A pellet as claimed in claims 1 to 4 of zinc/tin alloy having a melting point no higher than 430"C.
7. Sporting pellets as claimed in any one of claim 1 to 6 and substantially as hereinbefore described.
8. A method of producing a sporting pellet as claimed in claims 1 to 7, substantially as hereinbefore described.
9. A shot-gun cartridge containing a plurality of pellets as claimed in any one of claims 1 to 7.
10. A zinc-based alloy containing 0.5 to 2.0 of tin and 0.001 to 0.5E of lithium, with optionally small additions of copper magnesium or silicon.
GB8823798A 1987-10-29 1988-10-11 Improvements in or relating to metal shot and the production thereof Expired - Fee Related GB2211920B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB878725349A GB8725349D0 (en) 1987-10-29 1987-10-29 Metal shot

Publications (3)

Publication Number Publication Date
GB8823798D0 GB8823798D0 (en) 1988-11-16
GB2211920A true GB2211920A (en) 1989-07-12
GB2211920B GB2211920B (en) 1991-05-08

Family

ID=10626103

Family Applications (2)

Application Number Title Priority Date Filing Date
GB878725349A Pending GB8725349D0 (en) 1987-10-29 1987-10-29 Metal shot
GB8823798A Expired - Fee Related GB2211920B (en) 1987-10-29 1988-10-11 Improvements in or relating to metal shot and the production thereof

Family Applications Before (1)

Application Number Title Priority Date Filing Date
GB878725349A Pending GB8725349D0 (en) 1987-10-29 1987-10-29 Metal shot

Country Status (1)

Country Link
GB (2) GB8725349D0 (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU638299B2 (en) * 1990-12-11 1993-06-24 Nico-Pyrotechnik Hanns-Jurgen Diederichs Gmbh & Co. Kg A shot cartridge
WO1994025817A1 (en) * 1993-04-26 1994-11-10 Leif Persson Material primarily for sport-shooting ammunition
WO1995010753A2 (en) * 1993-10-14 1995-04-20 Vladimir Jezic Shot for shotshells
WO1996023193A1 (en) * 1995-01-26 1996-08-01 Federal-Hoffman, Inc., Doing Business As Federal Cartridge Co. Non-toxic bullet
DE19644235C1 (en) * 1996-10-24 1998-02-12 Grillo Werke Ag Scrap used for ammunition
WO1998020294A3 (en) * 1996-11-06 2002-10-24 John E Brown High-density sporting devices and methods
US7837809B2 (en) 2004-08-10 2010-11-23 Real Federacion Espanola De Caza Materials for the production of ecological ammunition and other applications
WO2012168530A1 (en) 2011-06-08 2012-12-13 Real Federacion Española De Caza Ecological ammunition
EP2878917A1 (en) 2013-11-29 2015-06-03 Real Federacion Espanola de Caza Chemical composition for manufacturing ammunition
CN107686908A (en) * 2017-09-04 2018-02-13 天津金力研汽车工程技术有限公司 Zinc-containing alloy for diel and preparation method thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1459528A (en) * 1973-03-06 1976-12-22 Canadian Patents Dev Metal shot
GB2007724A (en) * 1977-11-12 1979-05-23 Mizusawa Industrial Chem Process of low-melting-point metals
GB2179427A (en) * 1985-08-03 1987-03-04 Alloy Residues Limited Air gun pellets

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1459528A (en) * 1973-03-06 1976-12-22 Canadian Patents Dev Metal shot
GB2007724A (en) * 1977-11-12 1979-05-23 Mizusawa Industrial Chem Process of low-melting-point metals
GB2179427A (en) * 1985-08-03 1987-03-04 Alloy Residues Limited Air gun pellets

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
JP63097354 A *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU638299B2 (en) * 1990-12-11 1993-06-24 Nico-Pyrotechnik Hanns-Jurgen Diederichs Gmbh & Co. Kg A shot cartridge
WO1994025817A1 (en) * 1993-04-26 1994-11-10 Leif Persson Material primarily for sport-shooting ammunition
US5728349A (en) * 1993-04-26 1998-03-17 Persson; Leif Material primarily for sport-shooting ammunition
WO1995010753A3 (en) * 1993-10-14 1995-06-08 Vladimir Jezic Shot for shotshells
WO1995010753A2 (en) * 1993-10-14 1995-04-20 Vladimir Jezic Shot for shotshells
WO1996023193A1 (en) * 1995-01-26 1996-08-01 Federal-Hoffman, Inc., Doing Business As Federal Cartridge Co. Non-toxic bullet
AU693557B2 (en) * 1995-01-26 1998-07-02 Federal Cartridge Company Non-toxic bullet
DE19644235C1 (en) * 1996-10-24 1998-02-12 Grillo Werke Ag Scrap used for ammunition
EP0838655A1 (en) 1996-10-24 1998-04-29 Grillo-Werke AG Shotgun pellet
US6071359A (en) * 1996-10-24 2000-06-06 Grillo-Werke Ag Shot for use as ammunition
WO1998020294A3 (en) * 1996-11-06 2002-10-24 John E Brown High-density sporting devices and methods
US7837809B2 (en) 2004-08-10 2010-11-23 Real Federacion Espanola De Caza Materials for the production of ecological ammunition and other applications
WO2012168530A1 (en) 2011-06-08 2012-12-13 Real Federacion Española De Caza Ecological ammunition
EP2878917A1 (en) 2013-11-29 2015-06-03 Real Federacion Espanola de Caza Chemical composition for manufacturing ammunition
CN107686908A (en) * 2017-09-04 2018-02-13 天津金力研汽车工程技术有限公司 Zinc-containing alloy for diel and preparation method thereof

Also Published As

Publication number Publication date
GB8823798D0 (en) 1988-11-16
GB8725349D0 (en) 1987-12-02
GB2211920B (en) 1991-05-08

Similar Documents

Publication Publication Date Title
EP0788416B1 (en) Method of making composite shots
US2574357A (en) Method of and apparatus for forming solder pellets
CA2146124A1 (en) Method and apparatus for producing metal strip
GB2211920A (en) Metal shot for sporting pellets
JPH06172819A (en) Method of granulating molten metal
CN102719704B (en) Process method capable of improving comprehensive mechanical property of multielement zinc-aluminum alloy
CN108504900A (en) A kind of corrosion-resistant Environment-friendlyzinc zinc alloy
KR20170125139A (en) Metal-coated steel strip
WO2000003194A2 (en) Projectiles made from tungsten and iron
NO303723B1 (en) Procedure for molding and associated apparatus
US3928028A (en) Grain refinement of copper alloys by phosphide inoculation
NZ205446A (en) Low antimony lead-based alloy for batteries
CN105369116B (en) A kind of piebald cylinder jacket of centrifugal casting production and its production technology
AU742692B2 (en) Aluminium-bismuth bearing alloy and methods for its continuous casting
EP0058322B1 (en) Method for preparing rotund particles of salt-coated magnesium or magnesium alloy
US3960200A (en) Apparatus for liquid quenching of free jet spun metal
US6328823B1 (en) Aluminum sliding bearing alloy
US3360366A (en) Method of grain refining zinc
JPS5832567A (en) Manufacture of metallic shot
US5464487A (en) Method of making a hardened bullet
US5026433A (en) Grain refinement of a copper base alloy
US2193664A (en) Ammunition
JPS5914083B2 (en) Manufacturing method for zinc or zinc alloy shot balls
US3481732A (en) Processing lead alloy containing magnesium
JP3484989B2 (en) Manufacturing method of aluminum integrated caliper body for disc brake

Legal Events

Date Code Title Description
732E Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977)
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19991011