US694675A

US694675A - Gun-cartridge.

Info

Publication number: US694675A
Application number: US7982001A
Authority: US
Inventors: Robert W Scott
Original assignee: Individual
Current assignee: Individual
Priority date: 1901-10-24
Filing date: 1901-10-24
Publication date: 1902-03-04
Anticipated expiration: 1919-03-04

Description

N0. 694,675.A Patented Mar. 4, |902. R. W. SCOTT.

GUN CARTRIDGE.

(Application led Oct. 24, 1901.)

(No Model.)

.NIMH

' UNITED STATES PATENT Omen.

ROBERT W. SCOTT, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR OF ONE- HALF TO LOUIS D. WILLIAMS, OF ASHBOURNE, PENNSYLVANIA.

GUN-CARTRIDGE.

sPEcIFIcATioN forming part of Letters Patent No. ceacvavdatea Marce 4, 1902. Application filed October 24, 1901. Serial No. 79,820. (No model.)

To all whom it may concern:

Be itknown that I, ROBERT W. SCOTT,a citizen of the United States, residing in Philadelphia, Pennsylvania, have inventedV certain Improvements in Gun-Cartridges, of which the following is a specification.

This invention consists of means for checking or preventing the escape of gas beyond a projectile before itis securely seated in the riiing of a gun. Heretofore bullets used in small-arm ammunition and made of lead could generally be reliedupon to upset or expand diametrically upon the shock of discharge, so that but slight escape of gas occurredL before the soft metal was well entered in the riding of the barrel and the gas-vent thereby sealed. The'escape of gas around the bullet, even if comparativelyvslght, is sufficient to materially interfere with the line of flight of the bullet, for if a greater quantity of gas passes at one point on the circumference of the bullet than at another the latter will be eroded or cut away, so as to impair its symmetry and prevent it from following a true flight. This fact is so well known to expert marksmen that they seldom rely on fixed ammunition -that is to say, cartridges having the bullet crimped in the mouth of the cartridgecase-Lbut seat the bullet carefully but firmly in the rifling before int-roducing the cartridgecase, which contains the explosive only. Even when this method is employedyitis questionable whether there is not more or less escape of gas around the bullet because of the expansion of the metal of the g'un itself on the explosion of the charge. `Since the introduction ofnitro or so-called smokeless powders and hard-metal j acketedprojectiles the evils attending this forwardv escape of gas beyond the projectile have been multiplied and no adequate means have `thus far been devised to prevent it. With the old charcoal or black powder a very violent initial shock took place, and `with the soft-'lead bullet .a more or less effectualsealing of the vent occurred at an early stage in the forwardA travel of the ball through the barrel of thegun., Nitro powder, on the other hand, appears much slower in its initial combustion, and when anv attempt was recently made to use such powder in the Springfield rifle .45 caliberit was found that the escape of gas 4was far greater than with the black powder theretofore used.

In modern high-power rifles of small caliber and quick twist a soft-metal bulletcannot be used, as the twist of the rifle at the high velocity imparted to the bullet strips the latter, causi ng it to j ump the lands. Hence its flight is extremelyV erratic, and a `bullet having a lead core and a hard-metaljacket for mantle is therefore employed.v Such a bullet, however, owingto the presence of the mantle or jacket, offers great resistance to elndwiseV compression, and consequently upsets with great difficulty. Hence it haslbeen found necessary `to make the bullet of a diameter equal to the measurement across the grooves of the rifling and to permit it to protrude from the mouth of the shell and to have as long and snug a bearing asrpossible in the entrance to the rifiing. Unavoida'ble mechanical inaccuracies, however, prevent a perfectv mechanical kt, and evenl if the latter were yattainable it would only lessen and not prevent the escape of gas and consequent deformation of the bullet and injury to the vriling because ofl the beforementioned expansion of the metal of the barrel itself under the high initial pressure of eXplosion. Moreover, a bullet of the. character just mentioned, having buffa shallow seating in the mouth ofthe cartridge-casing, is liable to work loose, and the casings are very often split at the mouth by the constant strain on the thin metal which has been forced over the end of the bullet with a driving lit. To overcome these defects,resort has been had to various devices. Forinstance, acup-shaped copper member has been attached to the base of the bullet; but thisdoes not prevent the escape of gas,while it doesgive rise to another evilby frequently leavingthe fmuzzle separated from the bullet,and therefore, ofcourse, a source of danger to friendly troops in front and in the, line of lire, or if separationdoes not take place the cup acts as a rudder `and steers the bullet wildly. Another plan lhas been to simply recess the base of the bullet, so as to imparta flaringorcup shape thereto; but this does not set up quickly enough to prevent gas escape, and also detracts from accuracy of fire at high velocities.

I overcome the escape of gas around the pro- IOO jectile, whether in small-arms or large ordnance and whether a soft or hard metal' pror jectile is employed, by utilizing the initial expansion of the cartridge-casing itself to seal allforward Vent, and do not depend upon any forward movement of the projectile to cause that end.

In the accompanying drawings, Figure lis a longitudinal section, on an exaggerated scale, of a small-arm cartridge embodying my invention. Fig. 2 shows the projectile for such cartridge as prepared for application t0 the cartridge-casing. Fig. 3 illustrates the application of the invention to a projectile having a soft-metal point. Fig. 4 illustrates one method of adapting my invention to asoftmetal bullet. Fig. 5 shows part of a largecaliber projectile, illustrating the application of my invention thereto; and Figs. 6, 7, S, and 9 are views illustrating other constructions embodying my invention.

Referring to Fig. l, a cartridge-casing of the usual formis represented at l andthe bullet at 2, said bullet having a jacket 3, which has a cannelure or depressed portion 4, the metal of the jacket being formed at a point forwardly beyond this cannelure into a flange, which in the first instance projects outwardly from the-jacket, as shown in Fig. 2. The jacketed bullet is forced into the open mouth of the charged casing until the forward end of said casing contacts with the rear face of the flange 5, whereupon the forward portion of the vcasing is crimped into the cannelure and the flange 5 is pressed down over said crimped end of the casing, as shown in Fig. l. On the firing of the charge the first action which takes place is the diametrical expansion and longitudinal stretching of the casing l, the gas-pressure tending to raise or force outward the depressed forward end of the casing, while at the same time the longitudinal stretching of the casing tends to force the bullet forward. Under the pressure thus applied to the forward end of the casing the flange 5 of the jacket 3 is forced outwardly and against the wall of the cartridge-chamber, thereby effectually preventing any forward escape of gas, and as the pressure is continued and the inertia of the bullet is overcome said flange 5 tightly hugs the Wall of the cartridge chamber, and `when the rifling is reached said flange is forced downwardly and into the cannelure 4', so that when `the bullet issues from the muzzle of the gun no protruding part is presented to interfere with the true flight of the same.

When a soft-pointed bullet is used, the forward end of the partial-jacket 6 can be bent hackwardly over the crimped forward end of the cartridge-casing, as shown at 7 in Fig. 3, so as to form the desired gas-checking flange. In this case the jacket for the reception of the .bullet is in the form of a cup,'.which receives the base of said bullet and not only forms the gas-check, but protects the base of the bullet from deformation, such as would otherwise be caused by the upsetting action of the pressure upon it when the charge is fired.

In the case of an unjacketed bullet a flange 9 may be formed directly upon the bullet itself, as shown by dotted lines in Fig. 4, this flange being bent down over the crimped forward end of the cartridge-casing, as shown b v full lines in Fig. 4.

In large-caliber projectiles the flange may be formed upon the copper orother soft-metal driving-band l0 of the projectile, as shown, for instance, at ll in Fig. 5, the driving-band in this case having the cannelure 12, into which the forward end of the cartridge-casing is crimped or depressed. Y

The projectile shown in Fig. 6 has an oval or rounded base, which is a much better form than a square base, so far as concerns the ease of flight of the projectile through the air. In this case the jacket 6, which envelops the rear end of the projectile and forms the gas-check 7, also serves to prevent deformation of the rear end of the projectile by pressure, and thereby insures the retention by the projectile of the desired rounded form of base originally imparted to it. When a projectile of this form is used without soine efficient gas-checking device, the forward passage of the gas surrounding the projectilel seems to be assisted by the wedge-shaped space which surrounds the rear end of the projectile. Consequently the gas-checking ange forward of the base is of peculiary advantage in connection with a projectile of this class. It is not essential to the proper carrying out of my invention, however, that the gas-checking flange should be located forwardly of the base of the projectile, as substantially the saine operative effect in respect of gas escape can be secured by adopting the construction shown in Fig. 7, where the rear end of the jacket 3 constitutes the gas-check, the rear end of the bullet being reduced in diameter, so as to afford an annular space in side the jacket, into which the forward end of the cartridge-casing can be entered.

In a cartridge of this character the reduced portion of the base of the bullet may, if desired, be protected by a cap of hard metal, as shown, for instance, at 14 in Fig. S, or, if desired, an annular groove may be formed in the soft metal of the bullet itself for the reception of the forward end of the cartridgecasing, as shown, for instance, in Fig. 9.

In addition to forming an efficientgas-cheok the lip or flange on the projectile serves other useful purposes. Forfinstance, it acts as a positive stop to prevent the projectile from being forced back onto the explosive material in the cartridge-casing andis important in this connection, inasmuch as any encroachment upon the area of the explosive-chamber serves to greatly raise the breech-pressures when the charge is fired. Furthermore, the

IOO

suffices to retain the projectile in place, this i being of especial advantage in multishot cartridges, such as those shown and described in my application, Serial No. 40,675, dated December 21, 1900, in which the grip of the casing upon the base of the-leadingbullet is necessarilyvery short.l In such a cartridgev a gas-checking device isof .prime importance inA connection with the leading projectile, but isnot desiredV in connection with the Afollowing one, escape of gas around the latter being one of the means dependedupon to` ignite the,

charge which is interposed; between the two` projectiles.

I am aware that it has been proposed to se-4 cure a bullet to the forward end of a cartridgeV shell or casing by meansofa flange overlap, ping said forward endYV and pressed down firmly into contact with the casin g; but in all prior cartridges of; this class with which I am familiar the casingwas intended to be dis-` charged from the gun withthe bullet. Hence the'iiangeI upon the latter did not serve as, a. gas-check, for in order to perform this functionl the projectile` mustwhen the gun is fired beseparated from the cartridge-casing, the latter remaining in the breech of the gun.

p Having thusA described my invention, I- claim and desire to securebyLettersPatr.

1. A projectile .having a flange thereupon so disposed as to overlap the mouth of the casing which receives the explosive charge,- whereby, when` the projectile is fired, saidv fiangeY will be expanded .sovas to serve as a 3. A projectile having a gas-checking flange,-

and a cannelure intowhich said flange can be forced as the projectile passes through the bore of the gun. n l

4. A cartridge having a casing constructed for retention within the gun, and a projectile. having a gas-checkin g fiange and a cannelure.

v adjacent thereto into which the forward end of the casing is crimped, saidforward end of the casing being overlapped by the gas-checking flange.

5. Arcartridge having a easingv constructed,

for retention in the gun, and a projectile with gas-checking flange overlapping the mouth ofsaid casing, whereby the v latter has both incasingconstructed checking liange formed from the metal of said jacket, and constructed to overlap v a casing which receives the rear end of the projectile.

7. A cartridge comprising a projectile with. `jacket having a gas-checking flange formed thereon, and a casing whose mouth is overlapped by said flange.

8. A projectile having a jacket which incloses only a portion of the projectile and has anlexternal flange which constitutes a gas-check, and is constructed to overlap the mouth of the cartridge-casing which receives the rear end of theprojectile. l

9. A cartridge having a casing for receiving the explosive charge, and a projectile provided with a jacket which incloses only a portion of the projectile and has a flange overlapping the forward portion of the casing and serving as a gas-check. v

10. j A projectile having its base portion contained within a jacket whose forward portionV forms a gas-checking flange.

11. A cartridge having a casing for receive' ing the explosive charge and a projectile hav*- ing its base portion contained within a jacket whose forward portion forms a gas-checking fiangeco/verlapping the forward portion of the cartridgefcasing.

12. A cartridge comprisinga casing for receiving the explosive charge and a projectile whose forward portion forms `a gas-checking angewhich overlaps the forward-portion of IOO the casing and is pressed into said cannelure.

connection with which the projectile is in-` tended to beused.

14. A jacket constructedto envelop a portion of a projectile and having at its-forward end a dange so located as to receive within itv` the forward portion of a cartridge-casing in.`

connection with which-the projectile isintended to Vbe used.

l5. A projectile havinga rounded base, and a gas-checking flange in advance of the same.

16. A projectile having a rounded base and a jacketrinclosing the same so as to prevent its deformation by the upsetting pressure of the gases of explosion. v

17.' AA projectile having a roundedbase, a' jacket for inclosing the same,and a gas-check-r ing flange in advance of the base. 18. A projectile having a roundedl base, a jacket for inclosing the same,and agas-checking ange Vformed from the metal ofsaid` and a gas-.checking flange in advance of said' base, and overlapping the mouth of the carv tridge-casing.

20. A cartridge having a chargeacontaining casing, and a projectile having a rounded fIS base, and a jacket forming a flange which In testimony whereof I have sgned my overlaps the mouth of the Casing. name to this specification in the presence of 21. A cartridge having a eharge-oontaiuin g two subscribing witnesses.

casing and @projectile havingarounded base, ROBERT XV. SCOTT.

and a jacket nelosng said base and form- W'itnesses:

ing a flange which overlaps the mouth of the F. E. BECHTOLD,

casmg.

Jos. H. KLEIN.