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Publication numberUS2393648 A
Publication typeGrant
Publication dateJan 29, 1946
Filing dateFeb 20, 1942
Priority dateFeb 20, 1942
Publication numberUS 2393648 A, US 2393648A, US-A-2393648, US2393648 A, US2393648A
InventorsMartin Carl A
Original AssigneeMartin Carl A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Projectile
US 2393648 A
Images(1)
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Description  (OCR text may contain errors)

Jan. 29, 1946.

C. A. MARTIN PROJECTILE Filed Feb. 20, 1942 m 9 y M Patented Jan. 29, 1946 UNITED it STATES PATENT OFFICE 2,393,648 PROJEGTILE Carl A. Martin, Negaunee, Mich.

7 Application February 20, 1942, Serial No. 431,708 7 (01. 102-52) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 3 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes. without the payment to me of any royalty thereon.

This invention relates to a projectile and more particularly to an improved form of armor piercing projectile and method of making the same.

Modern armor plates which have proven to have the greatest protective qualities are, as is well known, provided with an extremely hard face by any one of several processes. Examination of projectiles after impact with such facehardened plates seems to show that the resistance to penetration of such plates is due to the fact that on impact there is a tendency for the head of the projectile to be shattered or upset by the blow of impact, in the happening of either event losing its power of penetration. However, if the shape of the projectile can be maintained and the body thereof kept intact until the hardened surface of the plate has been destroyed, there will generally be no difliculty in penetrating the underlying layers of softer material.

Prior attempts to reach this end in practice have involved the provision of a projectile having a head portion of such great hardness as to shatter the face of the plate. Attempts have been made by the provision of soft nose caps in advance of the hardened head and by controlled local heat treatment of the body to further increase penetration. However, eiforts to control the zone hardness of armor piercing projectiles of small caliber have not been successful as the small size of these projectiles precludes any effective variation in the heat treatment which is applied to the various zones of the projectile.

It is therefore an object of this invention to produce an armor piercing projectile or core therefor which, even in the small and medium calibers, will have optimum physical characteristics in respect to hardness and strength of each increment.

It is a further object to provide a method of producing such projectiles which will relieve critical shortages of strategic materials and which will release machine tools, such as the automatic screw machines, for other essential employment.

It is a further object to improve the economy and efiiciency with which such projectiles may be produced.

The exact nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing in which:

Figures 1, 2, and 3 are longitudinal sectional views of a projectile formed according to my invention and representing the products of the three principal steps of the method.

Figures 4, 5, 6, 7 and 8 are longitudinal sectional views of a projectile produced according to modifications of the method.

Figure 9 is a similar view of a modified form of projectile produced by a similar method.

Referring to the drawing by characters of ref erence there is shown in Fig. 1 a die I having a shape complementary to that of the desired projectile and provided with a pair of cooperating punches 2 and 3. Mixtures of powdered alloys or of the relatively pure constituents of the alloys are added to the die in such a manner that they are arranged in layers or strata along planes perpendicular to the long axis of the bullet. The metal powders used are chosen for the characteristics which are to be desired in the projectile. For example the tip zone 4 may be of material on the order of a hard mineral carbide with a suitable binder metal, While the head zone 5 is of a material which on alloying will produce a characteristically hard steel, and the base zone 6 is of a material which will produce a less hard but characteristically tough steel. As indicated in Fig. 2 the powdered mixtures are then subjected to pressure, preferably from each end simultaneously, to obtain a body having sufiicient strength and cohesiveness to resist ordinary handling. To promote adhesion at this stage it may be necessary to add a bindin constituent to the original mixtures.

The formed bullet may then be removed from the mold and subjected to a sintering process the details of which are determined in'a known manner by the materials being treated. Normally sintering will be done by radiated heat in closed boxes with sufiicient charcoal to combine with the oxygen of the air and form a reducin atmosphere. The finished bullet shown in Fig. 3 will be physically homogeneous and the physical properties of the various strata will be in accordance with the properties of the materials used therein; At the interfaces between the various strata there will be considerable difiusion and interalloying between the layers thus avoiding any abrupt changes in characteristics which might weaken the structure.

The modifications shown in Figures 4 to 7 inclusive correspond to the step shown in Fig. 2, previously described. ,7 The modifications consist in variations in the method of charging the die for the molding operation. In the form shown in Fig. 4 the addition of the mixture comprising zone 4 was gradually stopped and at the same time the delivery of the powdered mixture comprising zone 5 was gradually increased. A similar procedure resulted in a similar blending or gradual transition between zones 5 and 6. By choice of the rates of addition of the powdered material it is possible to producea smooth variation in composition so that hardness may. be made to vary decrementally from the tip while the toughness of the metal varies incrementally.

' ..-may be desirable.

In the forms shown in Figs. 5 to 7 each unit of the powdered composition has been introduced separately to the die and separately compressed. The shapes of the punch faces used in compressing each unit of the charges..may;be' variedias tions will be found in the fact that a composite structure may thus be produced in which each of the alloy compositions retains its own identity andits. own physical characteristics although asdesired to produce interfacial junctionsofiany desired section, those shown being merely illustrative of some of the possible variations. In

this way it is possible to carry a'core. oftougher? the application of final pressure to form the pro- I jectile body ready for sintering.

The modified form of projectile shown-inFig. 9 is of a type which would be particularly useful as an unjacketed-projectile and is provided with a soft nose ll] of powdered iron or other relatively soft material which on 'impact', serves to assist in penetration by lessening the tendency to ricochetand by supporting and lubricating the body during penetration. These functions are fulfilled in conventional. construction bymeans of a jacket and point filler or by soft capswelded, brazed, soldered, or mechanically secured to the projectile body. Such a'projectile might be provided with a rotating band or other conventional rifling engaging, means.

It will be obvious that a projectile body may be thus formed in any desired shape suitable for use directly or as a core for the conventional jacketed projectiles. titles of powdered materials" may be charged into thedies results in elimination of wastage of materials. In the typical projectile cores used at present ahigh percentage of metal is lost in turning the body in automatic screw machines from 'bar. stock. Such elimination of wastage results in increased economy of critical metals and the method is also economical in that a pressure molding operation replaces precision, machining from bar steel.

It .is generally contemplated that the harder The fact that exact quan-.

sociated in a homogeneous body with materials of greatly differing characteristics.

vI-claim:

1.'A- homogeneous projectilebody comprising heat treated. stratified mixtures of compressed powdered metallic products, the noseof'said body being relatively soft, the portion of said body adjacent the nose being of great hardness, and the remainder of said body being decrementally hard and incrementally tough and formed from a plural number of compositions, one of which is a heat treated ferrous metal of a high hardness and another of which is a heat treated ferrous metal of great toughness.

2.. A homogeneous projectile body comprising a sintered composite structure of mixtures of compressed metallic powders, the nose of said body comprising a relatively soft material, an armor piercing portion comprising a mixture of a hard metal carbide and a binder metal in rear of said nose, and: a base portion comprising a material varying decrementally in hardness and incrementally in toughness from said armor piercing portion, said base portion being formed from .a plural number of compositions, one of which-is a heat treated ferrous metal of high hardness and another of which is a heat treated ferrous metal of great'toughness.

3. A homogeneous projectile body comprising a nose portion of a; relatively soft metal, a hard armor piercing portion of amixture of metallic carbide and a binder metal behindsaid nose, and a-metallicbase portion varying decrementally in hardness and incrementally in toughness from said-armor piercing-portion, said metallic base portion being formed" from a plural number of compositions, one of which is'a heat treated ferrous metal of a high hardness and another of which is a heat treated ferrous metal of great toughness the portions of said projectile body being interfacially allowed with each other.

CARL -A. MARTIN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2669930 *Jan 5, 1946Feb 23, 1954Remington Arms Co IncSabot projectile
US3203349 *Sep 17, 1963Aug 31, 1965Kohlswa Jernverks AbProjectile or the like, preferably for armor-piercing weapons, and a method of manufacturing such a projectile
US4665828 *Nov 23, 1984May 19, 1987Voest-Alpine AktiengesellschaftPenetrator for a driving-cage projectile and the process of manufacturing the same
US4836108 *Jun 6, 1988Jun 6, 1989Gte Products CorporationMaterial for multiple component penetrators and penetrators employing same
US4869175 *Jul 10, 1987Sep 26, 1989Mcdougal John AImpact structures
US4872409 *Aug 17, 1987Oct 10, 1989Rheinmetall GmbhKinetic-energy projectile having a large length to diameter ratio
US5069138 *Jan 2, 1990Dec 3, 1991Lars EkbomArmor-piercing projectile with spiculating core
US5847313 *Aug 28, 1997Dec 8, 1998Cove CorporationProjectile for ammunition cartridge
US5877437 *Sep 16, 1996Mar 2, 1999Oltrogge; Victor C.High density projectile
US5936191 *May 14, 1997Aug 10, 1999Rheinmetall Industrie AgSubcaliber kinetic energy projectile
US6035501 *May 12, 1999Mar 14, 2000Rheinmetall W & M GmbhMethod of making a subcaliber kinetic energy projectile
US6149705 *Mar 2, 1998Nov 21, 2000Ut-Battelle, LlcNon-lead, environmentally safe projectiles and method of making same
US6174494Mar 20, 1998Jan 16, 2001Lockheed Martin Energy Systems, Inc.Non-lead, environmentally safe projectiles and explosives containers
US6317946 *Mar 8, 1999Nov 20, 2001Harold F. BealMethod for the manufacture of a multi-part projectile for gun ammunition and product produced thereby
US6371029 *Jan 26, 2000Apr 16, 2002Harold F. BealPowder-based disc for gun ammunition having a projectile which includes a frangible powder-based core disposed within a metallic jacket
US6551376Apr 21, 2000Apr 22, 2003Doris Nebel Beal Inter Vivos Patent TrustMethod for developing and sustaining uniform distribution of a plurality of metal powders of different densities in a mixture of such metal powders
US6581523 *Apr 30, 2002Jun 24, 2003Doris Nebel Beal Intervivos Patent TrustPowder-based disc having solid outer skin for use in a multi-component ammunition projectile
US6591730 *May 15, 2002Jul 15, 2003Doris Nebel Beal Intervivos Patent TrustCap for a multi-component ammunition projectile and method
US6607692Dec 31, 2001Aug 19, 2003Doris Nebel Beal Intervivos Patent TrustMixing metals heavier than lead with metals light than lead and micronized/oxidized polyethylene (accumulates electrostatic charge during handling); lead-free; uniformity
US6626114Apr 19, 2002Sep 30, 2003Doris Nebel Beal Intervivos Patent TrustProjectile having a disc and multiple cores
US6845719 *Jun 5, 2003Jan 25, 2005Lockheed Martin CorporationErosion resistant projectile
US7069834 *Feb 26, 2003Jul 4, 2006Doris Nebel Beal Inter Vivos Patent TrustTapered powder-based core for projectile
US7243588Nov 23, 2004Jul 17, 2007Doris Nebel Beal Inter Vivos Patent TrustPower-based core for ammunition projective
EP0073385A1 *Aug 13, 1982Mar 9, 1983GTE Products CorporationMultiple component penetrator projectile
EP0111712A1 *Nov 4, 1983Jun 27, 1984Rheinmetall GmbHSub-calibre penetrator with a high length-to-diameter ratio
EP0143775A2 *Nov 14, 1984Jun 5, 1985VOEST-ALPINE AktiengesellschaftSub-calibre penetrator and method of making the same
WO1999010702A2 *Aug 28, 1998Mar 4, 1999Cove CorpProjectile for ammunition cartridge
WO2000055569A2Mar 8, 2000Sep 21, 2000Harold F BealA multi-part projectile and method of making
WO2001055666A1 *Jan 26, 2001Aug 2, 2001Beal Harold FPowder-based disc for gun ammunition
WO2001069165A2 *Mar 7, 2001Sep 20, 2001Beal Harold FA multi-part projectile and method of making
WO2002090869A2 *Apr 30, 2002Nov 14, 2002Beal Harold FSolid outer skin powder-base disc for projectiles
WO2003002928A2 *May 15, 2002Jan 9, 2003Harold F BealCap for an ammunition projectile and method
WO2003029746A2 *May 8, 2002Apr 10, 2003Halverson Henry JDual core ammunition
WO2003073036A2 *Feb 26, 2003Sep 4, 2003Harold F BealAmmunition projectile including tapered powder-based core
Classifications
U.S. Classification102/519
International ClassificationF42B12/02, F42B12/06
Cooperative ClassificationF42B12/06
European ClassificationF42B12/06