US2611316A - Ammunition - Google Patents

Description

Sept. 23, 1952 P. P. ALEXANDER AMMUNITION Filed June 14, 1949 18212382303 Eda? M LEE 5302 2203;

Patented Sept. 23, 1952 AMMUNITION Peter P. Alexander, Beverly, Mass., assignor to Metal Hydrides Incorporated, Beverly,.Mass., a company-of Massachusetts I Application' June 14, 1949, Serial No. 99,097

This invention relates to bullets or projectiles for ammunition-torusein rifles, guns, etc. Such bullets or projectiles usuallyare fitted in a cartridge case containing an-explosiv'e chargewhich, when -detona'ted, propels the projectile from the gurrat a predetermined velocity. The cartridge case contains means for detonating the explosive charge, which commonly is a detonator cap fitted in the base of the cartridge case, adapted to be detonated by the impact of the gun hammer. 'In-some cases, a ring of a soft metal, such as copper, is fitted in an annular groove in the projectile for a purpose well known to those skilledinordnance.

Prior to the present invention it had been known that spar-ks are-produced when a hard metal, suchas iron, was subjected to the violent abrasive action of an abrasive Wheel rotating at high speed. When brittle iron is subjected to impact sufficient to break'itinto small pieces no sparks are produced. The action of an abrasive wheel upon iron generates considerable heat which raises the'temperature ofthe small particles removed sufficiently high to cause them to glow.

It also was known that certain alloys, such as alloys containing about; 70 per cent cerium and 30 per cent iron; produce sparks when subjected to mild abrasion, such as by rotating a small knurled wheel a partial revolution while contactingthe alloy under very slight pressure. The mild abrasion does not generate any substantial amount of heat. The production of sparks by these alloys has been explained by those skilled in the art as being caused by the removal of a multiplicity of small particles which immediately become ignited in air. Such alloys are referred to as pyrophoric alloys. They contain a large percentage of a very soft metal, namely, cerium.

Another pyrophoric alloy i described in the copending application of Robert J. Anicetti, Serial No. 746,329, filed May 6, 1947, now Patent No. 2,490,570. This pyrophoric alloy consists essentially of zirconium and lead in the proportions of 20 to 75 per cent of lead and 25 to 80 per cent of zirconium by weight. Like the cerium-iron alloy, the zirconium-lead alloy produces sparks when subjected to mild abrasion by rotating a small knurled wheel a partial revolution while contacting the alloy under very slight pressure. It too contains a very soft metal component, namely, lead.

In spite of the similarity in appearance and the above mentioned properties of the ceriumiron alloy and the lead-zirconium alloy, they .1 Claim.. (01.102-38.)

differ radically in at leastone property. Thus, I have made the surprising discovery that-when a piece-of the lead-zirconium alloy is subjected to a sudden heavy impact, instead of being broken into fragments, it is crushed to a fine powder and the whole mass set afire. The pres entinvention is based upon this discovery --and the conception of utilizing this peculiarproperty of the lead-zirconium alloy by embodying the alloy in projectiles for ammunition. I have dis covered that alloys which are essentiallyliead and zirconium in the proportions of 10 to per cent of lead and 30 to per cent of zir conium by weight possess this property and-are suitable for use in the practice of the invention. It the projectile is composed wholly of this alloy, I prefer to employ an alloy containing between about -50. to 60 per cent by weightof leadbe cause ofits better ballistic characteristics-.wIt was surprising to discover that" an alloy of fi-zir conium and lead, containing afhigh-percerrtage of lead possesses this peculiar property since "it was well known that bullets madeof lead o r' 1ea cl alloys theretofore tended to flatten upon striking atarget: f The alloy may contain substantial amountsof diluting metals such as titanium, manganese, tin, antimony,'etc., without detrimentally affect ing its basic characteristics. The combined amounts of lead and zirconium should not be less than about 60 per cent by weight of the alloy. I prefer, however, that the alloy contain not more than minor amounts of diluents.

In accordance with the present invention, ammunition for rifles, guns, etc., is provided in which the bullets or projectile is formed either wholly or in part of the pyrophoric alloy of lead and zirconium. In accordance with one aspect of the invention, a small piece of the pyrophoric alloy may be secured in the tip of the bullet such as the hole in the open point bullet, to provide ammunition particularly suitable for target practice either in daylight or in darkness. When such a bullet strikes a hard target, the alloy is set afire and informs the marksman, either military or civilian, as to the location of the hit. If desired a small amount of a smoke producing compound, such as black powder, magnesium metal, etc., may be placed in the bullet so that it is ignited by the pyrophoric alloy when the bullet strikes the target, thus supplementing the flame produced by the pyrophoric alloy and producing smoke which can be seen by the marksman. If desired, any known incendiary composition may be placed in the bullet 0r projectile so that it may be crushed under oil or in a neutral protective atmosphere, such as argon, to form coarse particles which may be mixed with a binder such as glyptol, and shaped to desired form by molding, extruding, etc. While a fine powder ofv about 325 mesh still is crystalline; it cannot-bet crushed further and is not desirable for use in the practice of the invention. The. particle. size should be such that the particle will split or crush at the predetermined velocity for which. the at ticle of ammunition is designed to propel the projectile against. the target. Where: the predetermined velocity is about 10.00 feet per. second,

7 the'particle size. should be of. the order of 100 mesh.

Theinvention, therefore. in its" broad aspect contemplates ammunition inwhichat. least a portion of. the bullet or projectile is formed of. a pyrophoric. alloy. In one embodiment, a piece of pyrophoric alloy is securedin a. hole in the tip 01 the bullet so as to project forward therefrom. The act-ionof thepyrophoric alloy may be supplemented by an additional smoke and. flame producing. compound: adapted. to be. ignited. by the sparks. or flameiproduced by the. pyrophoric alloy when the bullet. impacts a hard. target. When theentire bulletor. projectile is a pyrophoric alloy oi zirconium-lead, the lead component should. be relatively high sothat the density of the alloy is notv less than. about; 6.5. because of. its better ballistic characteristics. 1

' The invention isillustrated further in the accompanying drawing, in which;

EigrLi's anelevational view of. apieceoflammunifihnsembodying. the invention; and- Fig.2 is an elevational view, partly in section, 01 an. open point bullet embodyingv the invention.

Thev embodiment illustrated in Fig.. 1. comprises 7 a: cartridge case- In of brass. intothe open end. or

v 4 which a, bullet or projectile II is fitted. in the usual manner. The projectile I l is formed of an alloy which is essentially zirconium and lead. A ring 12 of copper may be fitted into an annular groove formed in the body of the projectile near its rear end.

Fig. 2 illustrates a piece of ammunition for small arms. having an operrpoint expanding bullet l3 fitted in the open end ofa, brasscartridge case M. The bullet I3 may be formed of lead or other metal commonly employed and is provided with a hole. IS in its tip. As illustrated, a smoke producing compound l6, such as black powder, is placed in the bottom of the hole I 5 and a piece H of the" pyrophoric. alloy is fitted in the hole so as to project forwardly a short distance from the tip of. the. bullet.

I This application is a continuation-in-part of mycopending application, Serial No. 18,642, filed April 2, 1948, now abandoned.

I.claim:

In an. article of. ammunition having; a cartridgecase and. a projectile fitted. therein. and in which a portionof the. projectile isignitible. uponimpact with a target, the improvement wherein. said ignitible. portion is av pyrophoric. alloy consisting essentially of. zirconium. and betweenabout to per cent of lead by weight and. projects forwardly from. the tip of the projectile and is thereby adapted to come indirect contact withfa hard target whereby the force of impact therewithv causes. said. alloy to be crushed to a finely divided condition and thusv be set afirel PETER P. '1

REFERENCES CITED The: following references are of record in the file of this patent:

UNITED sTnrrEs. PATENTS I Great. Britain-1.1--. une 1551933

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