US3276322A

US3276322A - Cartridge guide for an automatic gun

Info

Publication number: US3276322A
Application number: US413572A
Authority: US
Inventors: Christiansson Carl Mauritz
Original assignee: Bofors AB
Current assignee: Saab Bofors AB
Priority date: 1963-11-26
Filing date: 1964-11-24
Publication date: 1966-10-04
Anticipated expiration: 1983-10-04
Also published as: ES306455A1; AT251447B; NL6413766A; BE656275A; GB1078039A; CH443972A; DE1428759B2; DE1428759A1; DE1428759C3

Description

Oct. 4, 1966 c. M. CHRISTIANSSON 3,

CARTRIDGE GUIDE FOR AN AUTOMATIC GUN Filed Nov. 24, 1964 2 Sheets-Sheet l FIG. 2

INVENTOR.

CARL MAUR/TZ CHRIST/ANSSON BY I W Oct. 4, 1966 c. M. CHRISTIANSSON 3,275,322

CARTRIDGE GUIDE FOR AN AUTOMATIC GUN 2 Sheets-Sheet 2 Filed NOV. 24, 1964 INVENTOR. CA R1. NZAUR/TZ CHR/ ST/ANS SON BY M M ATTORNEY:

United States Patent f 3,276,322 CARTRIDGE GUIDE FOR AN AUTOMATIC GUN Carl Mauritz Christiansson, Bofors, Sweden, assignor to Aktienbolaget Bofors, Bofors, Sweden, a corporation of Sweden Filed Nov. 24, 1964, Ser. No. 413,572 Claims priority, application Sweden, Nov. 26, 1963, 13,078/63 4 Claims. '(Cl. 89-33) The invention relates to a device for guiding cartridges in an apparatus for ramming cartridges into the cartridge chamber of an automatic gun, and more'particularly to a device of this kind comprising a cartridge-guide in which the cartridge occupies a position essentially co-axial with the barrel bore and to which the cartridge is brought from a cartridge magazine of the gun before ramming.

Due to the fact that the bottom part of a cartridgecase comprises a flange which has a somewhat larger diameter than the cartridge-case jacket, it is necessary that the cartridge-guide as well as the breech ring and the breech block of the gun, which are located between the cartridge chamber and the cartridge-guide, comprise longitudinally extending guide means so arranged that they together define a guide surface having at least as large an internal diameter as the external diameter of the flange of the cartridge-case bottom, so as to leave the flange free to pass the cartridge-guide, the breech ring and the breech block when the cartridge is rammed.

Further, and due to the fact that the case bottom-flange of the cartridge has a larger diameter than the case jacket, and the jacket, in its turn, has a larger diameter than the projectile, which is held in a tapering neck of the cartridge-case, the cartridge will rest in the cartridge-guide in a position, in which the axis of the cartridge is directed obliquely forward-downward as seen from the cartridgecase bottom, and is thus not located so as to be accurately co-axial with the barrel bore. Such an inclined position of the cartridge relative to the barrel may cause difficulties in connection with the ramming unless provisions are made to prevent such slant of the cartridge during ramming. In particular with the fast ramming movements as are used in rapidly firing guns, dangerous inertia forces and other difliculties arise, restricting the loading speed. This is due to the fact that the cartridge-chamber has a smaller diameter than the guide surfaces of the cartridge guide, the breech ring and the breech block which are dimensioned with respect to the diameter of the bottomflange of the cartridge. For this reason, the front part of the cartridge may strike against the rearward edge of the cartridge-chamber and be blocked, or at least be exposed to a hard lateral shock when pushed into the cor rect position in the cartridge-chamber.

One object of the invention is to provide a ramming mechanism in which the aforementioned disadvantages are essentially eliminated. With this object in view the invention relates to a cartridge guide device, comprising a guide means arranged to lift the front part of the cartridge during the movement of the cartridge into the cartridgechamber, so that the cartridge occupies a position essentially co-axial with the cartridge-chamber during ramming thereby making it possible for the cartridge to run into the chamber without the front part thereof striking against the rear edge of the chamber, or being otherwise exposed to interfering powerful lateral forces.

The invention thus relates to a cartridge guiding device of the kind comprising a cartridge-guide having internal surfaces for guiding a cartridge during ramming which together define an at least part-cylindric guide means located rearward of and being coaxial with the cartridge chamber of the gun barrel. The guiding device further comprises at least one guide member, which is 3,276,322 Patented Oct. 4, 1966 carried by a pivot located below said guide surface and is pivotal about said pivot between a front position in which an end of said guide member extends into said cartridge-guide internally of the guiding surfaces thereof and a rear position in which the guide member is located externally of said guide surface. The device further com prises directional force means arranged to swing said pivotal guide member into said front position and against the action of which the member is pivotal into its rear position. Preferably, the distance over which the guide member extends into the cartridge-guide internally of the guide surface thereof in its front position equals the difference between the largest radius of the bottom flange of the cartridge-case and a radius of the jacket part of the cartridge-case. The cartridge, when lifted by the guide means during ramming of the cartridge, will then be lifted into a position substantially co-axial with the axis of the cartridge-chamber of the barrel whereby the cartridge can be rammed without parts of the projectile or the neck of the cartridge-case being exposed to lateral shocks during ramming.

The fact that the rear part of the cartridge is pushed upwardly a distance by the pivotal guide member when the flange of the cartridge passes the guide member during ramming, does not cause inconvenience. At this moment, the front part of the cartridge has already entered so far into the barrel that it is smoothly guided by the internal surfaces of the cartridge-chamber in the barrel.

Due to the fact that a guide member according to the invention is arranged pivotal rearwardly out of the way of the flange of a rearwardly ejected cartridge-case, the ejection may proceed without interference, provided, of course, that the mass of each pivotal guide member and the directional force acting thereon are selected in such a manner that the exerted lateral force and thus the acceleration of the cartridge-case in a direction perpendicular to the axis of the cartridge guide by the cartridgecase striking against the guide member are sufliciently small.

In a preferred embodiment of a cartridge-guide the guide surfaces, which together constitute the cartridgeguide, are so arranged that the cartridge is guided around its periphery, the guide surfaces thus together defining a complete, generally cylindrical guide means, which has an internal diameter corresponding to the external diameter of the bottom-flange of the cartridge. With such a cartridge-guide, a guide member according to the invention, which normally is in its front position in which it protrude-s internally of the generally cylindrical guide means, may constitute an obstacle for the bottom flange of the cartridge during ramming. To avoid this, the generally cylindrical guide means at such part thereof in its "longitudinal direction at which the guide member in its front position extends inwardly of the cylindrical guide surfaces, is widened upwardly a distance at least equalling the distance by which the guide member extends upwardly of the cylindric guide surfaces. The guide means thus comprise a bulging surface extending upwardly of the major part of the generally cylindric guide surfaces and the bottom-flange of the cartridge can move past the guide member or members during ramming without getting blocked.

The invention will become more fully apparent from the following description of a preferred embodiment as illustrated in the accompanying drawings, in which:

FIG. 1 is a longitudinal vertical sectional view of the rear part of a gun barrel, the breech ring and breech block of the gun, and of a cartridge-guide according to the invention, the figure showing a cartridge at a moment of its motion through the cartridge-guide during ramming and before the front part of the cartridge has moved upwards under the influence of a guide member;

FIG. 2 is a similar sectional view showing the cartridge in a position in which it has ben aligned with the cartridgeohamber of the barrel during ramming;

FIG. 3 shows the same details during ejection of a cartridge-case through the cartridge-guide after firing; and

FIG. 4 is .a perspective View illustrating an embodiment of a cartridge-guide according to the invention more in detail.

FIGS. 1 to 3 show a gun barrel 1 having a cartridgechamber 2 and a breech 'ring 3. A cartridge guide, generally designated 4, is arranged rearwardly of the breech ring 3 and in alignment with an opening 5 in the breech ring, through which opening each cartridge is to be rammed into the cartridge-chamber 2. During ramming a cartridge 7 moves past and above a breech block 6 into a final position in the cartridge-chamber in which the bottom-flange 8 of the cartridge-case abuts against the rear edge of the cartridge-chamber. In this position of the cartridge the breech block 6 can be pushed into a position behind the cartridge-case bottom before firing.

The diameter of the cartridge bottom flange 8 represents the largest diameter of the cartridge, and the cartridge tapers successively from the bottom to the top thereof, the diameter of the projectile 9 being much smaller than the bottom flange diameter. Consequently, the cartridge occupies a position in the cartridge guide which is somewhat oblique relative to an axis common to the barrel bore, the cartridgescham-ber of the barrel and the cartridge guide. To bring the cartridge into a position, which is substantially co-axial with the cartridge-chamber, the guiding device comprises, according to the invention, at least one guide member, which in the embodiment schematically illustrated in FIGS. 1 to 3 is represented by a guide lug 10 carried by an arm 13. The arm is pivotal about a pivot 12 located below and outside a guiding surface 11 of the guide 4. By means of a directional force, as illustrated represented by a spring 16 actuating a lever 17 fastened to arm 13, the guide member is normally held in a front or forward position, FIGS. 1 and 2, in which it is swung upwardly through an aperture 14 against an abutment member 15. In this front position guide lug 10 protrudes above the guide surface 11 a distance which preferably substantially corresponds to the difference between the radius of the cartridge-flange 8 and the radius of the substantially cylindric outer jacket surface 18 of the cartridge.

In FIG. 1, the cartridge 7 is illustrated in a position, in which it rests on the guiding surface 11 of the guide 4 with the edge of its flange 8 and the front portion of the cylindric surface 18 of the jacket, that is, the cartridge is in a position before it commences to slide upward-s over guide lug 10 with its tapering neck 19.

Assuming that no guiding means corresponding to guide lug '10 were present; the cartridge, when moving further forward during the ramming, would then hit the rear edge 20 of the aperture of the cartridge-chamber 2, the

guide surfaces

21 and 22 of breech block 6 and breech ring 3, respectively, being in alignment with the guiding surfac 11 of the cartridge-guide and thus located below the lower edge of the cartridge-chamber a distance, which corresponds to the distance by which the bottom-flange 8 extends externally of the cartridge-jacket adjacent the bottom-flange.

Due to the provision of the guide member comprising guide lug 10 and arm 13 the cartridge will, when moving forward from the position illustrated in FIG. I, slide upwardly over lug 10 and thus be pushed into alignment with the axis of cartridge-chamber 2. Accordingly, the cartridge can move forward into the cartridge-chamber (without the projectile or the front part of the cartridgecase neck 19 striking against the rear edge 20 of the cartridge-chamber or the internal walls of this chamber.

During the forward movement of the cartridge during ramming, the flange 8 must also pass past the guide lug 10. To make this possible, the cartridge-guide comprises a widened portion in the form of a bulge 23 on the upward side thereof. This bulge 23 has a shape such that flange 8, when .sliding upwards via lug 10, can pass freely through the guide 4 including the part thereof, where the rear portion of the cartridge is lifted by the guide member 10', 13 during ramming.

When the cartridge has been fired and the cartridgecase is ejected backwardly from the cartridge-chamber, the velocity of the cartridge-case is so high, that a failure may occur if the bottom-flange of the case would be forced to move along a stationary or fixed guide member having a shape such as the guide lug 10. By arranging the guied lug on a pivotal arm as illustrated, the guide lug can swing backwardly out of the way of the flange against action of spring 16, as it is indicated in FIG. 3, so that the cartridge case, when ejected, can move along an essentially linear path.

FIG. 4 illustrates more in detail an embodiment of a cartridge-guide according to the invention. In this embodiment, the cartridge-guide has an upper part comprising two guide bars 31 fastened to the breech ring 3 of the gun by means of a flange 30, a longitudinal opening 32 being provided to receive a ramming member, not illustrated in the drawings, which is movable within the opening while bringing the cartridge with it during ramming.

The bottom part of the cartridge-guide comprises two guide bars 33, which are both supported on front and rear arms 34 pivotal about pivots 35 between the positions illustrated in FIG. 4 in which they can .support a cartridge inserted into the cartridge-guide, and positions in which they are pivoted apart, so that a cartridge may be inserted into the cartridge-guide from below by cartridge conveying means, which are not illustrated in the drawing as not constituting part of the invention.

Prior to ramming, the cartridge thus rests on the guide bare 33 in a position to be brought to the cartridgechamber, which, in the same manner as illustrated in FIGS. 1 to 3, is located in front of breech ring 3. The internal surfaces 36 of

guide bars

31 and 33 together constitute the cartridge guiding surfaces of the device, said guiding surfaces being located at a distance from each other corresponding to the diameter of the bottomflange of a cartridge.

A guide member, which, as is described with reference to FIGS. 1 to 3, comprises guide lug 10' carried by arm 13, is arranged adjacent the front end of each bar 33 and piovtal about pivot 12, each mounted on a front arm 34. In its normal front or forward position each guide member is forced against abutment member 15 by means of spring 16 actuating lever 17. Each one of said guide members is, as is also described above with reference to FIGS. 1

to 3, pivotal rearwardly when exposed to forces exerted thereon by a cartridge-case ejected rearwardly after firing.

While the invention has been described in detail with respect to certain now preferred examples and embodiments thereof, it will be understood by those skilled in the art, after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention, and it is intended, therefore, to cover all such changes and modifications in the appended claims.

What is claimed is:

1. A guide device for guiding a cartridge including a cartridge casing having a cylindrical portion with a bottom flange of -a diameter wider than the cylindrical casing portion and a generally conical projectile fitted in the casing, while being rammed into the cartridge chamber of a gun, said device comprising an elongated cartridge-guide means having an inner peripheral outline fitting the diameter of the bottom flange of the cartridge casing, said guide means being mounted in communication with and forming a continuation of the cartridge chamber in a position in which the center axis of the guide means is in axial alignment with the center axis of the cartridge chamber for guiding the cartridge from the guide means into the cartridge chamber, said cartridge while being in the guide means having a downwardly slanted position in reference to the center axis of the guide means, a guide member, mounting means supporting said guide member adjacent to the forward end of the guide means facing the cartridge chamber, pivotal about an axis transverse of the common center axis of the cartridge chamber and the guide means and located externally and below the bottom side of said guide means for pivoting said guide member lengthwise of said common center axis between a forward position in which a portion of said guide member protrudes upwardly into said guide means to lift the projectile and the cylindrical portion of the cartridge while passing said protruding guide member portion from said slanted position into a position substantially coaxial with the axis of the cartridge chamber and a rear position in which said portion of the guide member is withdrawn from said protruding position, and a directional force means biasing the guide member into said forward position, said guide member being pivotal toward its rear position against the action of said force means when exposed to a force in the rearward direction of the guide means.

2. A device according to claim 1, wherein said guide member in its forward position extends into the cartridgeguide means a distance substantially equal to the difference between the maximum radius of the bottom flange of the casing of the cartridge and the radius of the cylindrical portion of the casing of said cartridge.

3. A device according to claim 1, wherein said cartridge-guide means is radially widened opposite said guide member to accommodate the bottom flange of a cartridge casing passing through the guide means.

4. A device according to claim 1, wherein said cartridge-guide means comprises several lengthwise parallel guide bars restricting lateral movement of the cartridge in all lateral directions perpendicular to the longitudinal axis thereof and defining a tubular member, and wherein said cartridge-guide means at a portion substantially diametrically opposite to said guide member when the same is in its forward position, comprises a radially widened portion permitting passage of the bottom flange of the cartridge past said guide member portion in its forward position when the cartridge is guided into the cartridge chamber during ramming. 7

References Cited by the Examiner UNITED STATES PATENTS 2,907,251 10/ 1959 Sahlberg 89-47 FOREIGN PATENTS 117,523 2/ 1945 Australia.

BENJAMIN A. BORCHELT, Primary Examiner.

FRED C. MATTERN, 1a., Examiner.

S. C. BENTLEY, Assistant Examiner.

Claims

1. A GUIDE DEVICE FOR GUIDING A CARTRIDGE INCLUDING A CARTRIDGE CASING HAVING A CYLINDRICAL PORTION WITH A BOTTOM FLANGE OF A DIAMETER WIDER THAN THE CYLINDRICAL CASING PORTION AND A GENERALLY CONICAL PROJECTILE FITTED IN THE CASING, WHILE BEING RAMMED INTO THE CARTRIDGE CHAMBER OF A GUN, SAID DEVICE COMPRISING AN ELONGATED CARTRIDGE-GUIDE MEANS HAVING AN INNER PERIPHERAL OUTLINE FITTING THE DIAMETER OF THE BOTTOM FLNAGE OF THE CARTRIDGE CASING, SAID GUIDE MEANS BEING MOUNTED IN COMMUNICATION WITH AND FORMING A CONTINUATION OF THE CARTRIDGE CHAMBER IN A POSITION IN WHICH THE CENTER AXIS OF THE GUIDE MEANS IS IN AXIAL ALIGNMENT WITH THE CENTER AXIS OF THE CARTRIDGE CHAMBER FOR GUIDING THE CARTRIDGE FROM THE GUIDE MEANS INTO THE CARTRIGDE CHAMBER, SAID CARTRIDGE WHILE BEING IN THE GUIDE MEANS HAVING A DOWNWARDLY SLANTED POSITION IN REFERENCE TO THE CENTER AXIS OF THE GUIDE MEANS, A GUIDE MEMBER, MOUNTING MEANS SUPPORTING SAID GUIDE MEMBER ADJACENT TO THE FORWARD END OF THE GUIDE MEANS FACING THE CARTRIDGE CHAMBER, PIVOTAL ABOUT AN AXIS TRANSVERSE OF THE COMMON CENTER AXIS OF THE CARTRIDGE CHAMBER AND THE GUIDE MEANS AND LOCATED MEANS TERNALLY AND BELOW THE BOTTOM SIDE OF SAID GUIDE MEAN FOR PIVOTING SAID GUIDE MEMBER LENGTHWISE OF SAID MEANS MON CENTER AXIS BETWEEN A FORWARD POSITION IN WHICH A PORTION OF SAID GUIDE MEMBER PROTRUDES UPWARDLY INTO SAID GUIDE MEANS TO LIFT THE PROJECTILE AND THE CYLINDRICAL PORTION OF THE CARTRIDGE WHILE PASSING SAID PROTRUDING GUIDE MEMBER PORTION FROM SAID SLANTED POSITION INTO A POSITION SUBSTANTIALLY COAXIAL WITH THE AXIS OF THE CARTRIDGE CHAMBER AND A REAR POSITION IN WHICH SAID PORTION OF THE GUIDE MEMBER IS WITHDRAWN FROM SAID PROTRUDING POSITION, AND A DIRECTIONAL FORCE MEANS BIASING THE GUIDE MEMBER INTO SAID FORWARD POSITION, SAID GUIDE MEMBER BEING PIVOTAL TOWARD ITS REAR POSITION AGAINST THE ACTION OF SAID FORCE MEANS WHEN EXPOSED TO A FORCE IN THE REARWARD DIRECTION OF THE GUIDE MEANS.