US475061A - krnka - Google Patents

Description

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MAGAZINE GUN. No. 475,061. Patented May'l?, 1892.

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No. 475,061. Patented May 17, 1892.

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6 Sheets-Sheet 5. K. KRNKA. MAGAZINE GUN.

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No. 475,061. Patented May 17, 1892.

(No Model.) 6 Sheets- Sheet 6.

` K. KRNKA.

MAGAZINE GUN.

No. 475,061. Patented May 17, 1892.

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KARL KRNKA, OF LONDON, ENGLAND, ASSIGNOR TO THE KRNKA REPEAT- ING RIFLE COMPANY, LIMITED, OF SAME PLACE.

MAGAZINE-G UN.

SPECIFICATION forming part of Letters Patent No. 475,061, dated May 1'7, 1892.

' Application sied March s1, 1890.

To all whom it may concern:

Be it known that I, KARL KRNKA, residing at London, England, have invented certain new and useful Improvements in Repeating Firearms, o f which the following is a specilication.

This invention is designed, rst, to reduce as much as possible the Weight of the breechbolt while retaining sufficient strength to in- Io sure absolute security. To effect this, the breech-bolt, which may be elsewhere of slight dimensions, has at its front end a strengthened head, on which are situated three radial breech-boltribs at angles of one hundred and twenty degrees to one another, which take the force of the recoil from the explosion. To these three breech-bolt ribs correspond guiding-grooves in the receiver, which run into a circular groove behind the barrel end,

zo so that by pushing the breech-bolt forward and turning it through sixty degrees the breech is closed. In consequence of the arrangement ofthe three breech-bolt ribson the periphery of the breech-bolt head, the force of recoil, acting on the latter when the rifle is lired, will always lie between the three supporting-points.

A further peculiarity ofthe breech-bolt consists in the cartridge-extractor being situated 3o on a ring loosely surrounding the breech-bolt.

This extractor is guided in a'groove of the receiver and is freely elastic when the breechbolt is pushed forward, while its front end', when the breech-bolt is drawn back, is engaged under the neck of the breech-bolt, and thus stiffened. This is effected by means of a projection on the cartridge-extractor entering into a correspondiugly-wider circular groove, the front half of which is dovetailed or un- 4o dercut, so that the said projection of the eX- tractor engages under the dovetail when the breech-bolt is pulled backward. Further, as regards the breech-bolt, the locking of the saine when the firing-pin is cocked is effected 45 by the sear entering a groove of t-he breechbolt cylinder.

The improvementsin the magazine consist in the catch securingthe magazinein araised or lowered position, in a longitudinal slot` of 5o the trigger-guard, and in a cartridge-carrier,

plan of the saine.

serai No. 346,126, (No motten the front end of which is slotted to allow of removal for cleaning.

In order that my invention may be the'better understood, I now proceed to describe the same in relation to the drawings hereunto annexed, 5 5

reference being had to the letters marked thereon.

Likeletters refer to like parts'in the Various figures.

Figure 1 is a side elevation of therifle with 6o the breech closed but uncooked. Fig. 2 is a Fig. 3 is a longitudinal section of the rifle with the breech-bolt pulled back. Fig. -t is a transverse section according to the line frac. Figisa'plan of the receiver. 65 Fig. 6 is aside elevation of the same. Fig. 7 shows the receiver, seen from below. Fig. 8 is a rear end view ofthe receiver. Fig. 9 isa front View of the sanne.l Fig. 10 is a longitudinal section of the breech-bolt closed and uncooked. 7o Fig. 1l is a transverse section according to the line Fig. 12 is a frontviewof the breechboltl in the saine position as Fig. 10. Fig. 13 is a plan of the breech-bolt cocked and before total closure. Figs. 14 and l5 are rear end and 75 front end Views according to Fig. 13. Figs.

16 and 17 are a longitudinal section and side elevation, respectively, of the breech-bolt according to Fig. 13. Fig. 1S is a transverse section according to the line 002 9:2, and Fig. 19 8o vis a front end View, both corresponding to Fig. 17. Fig. 2O shows the breech-bolt, as seen from be1oW,.in the same position as Fig. 13. Fig. 21 is a front end View according to Fig. 20. Fig. 22 is a longitudinal section of the 85 breech-bolt cocked, closed, and with the firing-pin secured. Fig. 23 is a transverse section according to the line .x3 fc3., Fig. 24 is a front end View corresponding to Fig. 23. Fig.

25 is a plan of the trigger-guard. Fig. 26 is a 9o side View of the same. Fig. 27 is a frontend View of Fig. 26. Fig. 2S shows lthe triggerguard, as seen from below. Figs. 29 and 30 are views of the trigger-bar. Figs. 31 and 32 are views of the trigger-springs. Figs. 33 and 95 34 are views of the sear. Figs. 35, 36, and 37 are views of the magazine-catch. Fig. 38 is a plan of the magazine filled. Fig. 39 is a4 longitudinal section of the same. Fig. 40 is a transverse section of the empty magazine acroo cording to the line x4 x4. Figs. 4l. and 42 are views of the cartridge-follower.

The breech-bolt head A is so formed that on its end are situated three breech-ribs d of equal size, extending exactly radially from the body of the breech-bolt head and at equal distances. During tiring the flattened shoulders of these lthree breech-ribs rest against the collar-like steps f in the receiver F, Fig. 9, in which is formed the cylindrical chamber f, which is of such a diameter that the breech-ribs can rotate in the same around the aXis of the bolt. The collar or shoulder f thus formed is recessed at. three places, serving to receive the breech-bolt and coinciding with three grooves f7, corresponding to the three before-mentioned breech-ribs d. These three grooves fT run through the whole length of the receiver and into the cylindrical chamber f. These grooves are best shown in Figs. 8 and 9 and are designed to allow the forward and backward movement of the breech-bolt and the three breech-ribs d, respectively. As soon asthe three breech-ribs a., Fig. 1S), have been pushed into the chamber f they are turned sixty degrees around the axis of the breech-bolt by means of the handle b, whereby the perfect symmetrical closure of the breech is effected, because the resting-points of this locking mechanism lare arranged on the periphery of the breech-bolt at equal distances, and because the three bearn ing points or surfaces distribute well the pressure and at the same time permit a small rotation of the breech-bolt to complete the locking. The breech-bolt head Ais hollowed longitudinally for the reception of the firingpin and is screw-threaded to enable the breechbolt head to be screwed to the center piece B. The rigid connection of these two parts (see Fig. 16) is effected by means of the screw Z9 in such a manner that both parts make their rotary movements simultaneously. The breech center piece B is also hollowed longitudinally to receive the firing-spring CZ and the longitudinal part of the firing-pin D;

From the upper surface of the center piece B protrudes the handle l), by means of which the breech is closed or opened. To close the breech, the handle b is pushed. forward and' In order to then rotated toward the right. open the breech, the handle is turned toward the left and then pulled back. It isintcnded that this symmetrical breech-bolt head may,

be used for a straight-pull breech-bolt, in

which case the rotation of the breech-ribs is effected automatically at theend of the forward movement of the handle wit-hout it being necessary to first turn the handle. lt may be used in this manner, for instance, in a straight-pull breech-bolt system. From the breech center piece B projects farther a projection b2, which serves, first, as a boss for the screw b, and, secondly, in combination with a socket-handle b, to limit the rotation of the breech-bolt to the proper angle, and when the breech is opened the projection b2 comes against the left wall of the receiver, and thus prevents further rotation in the opposite direction; thirdly, the projection b2 is also intended to loosen the jammed cartridge-ease after firing and when the breech is opened, so that the empty ease cannot offer any resistance to the backward movement of the breech -bolt. During the rotation of the breech-bolt to the left (see Fig. 2) this projection b2 comes against the oblique facef and slides along the same, so that without direct manipulation by the hand in this direction the breech-bolt is pushed back tive millimeters before the riieman commences the direct pulling backy of the breech-bolt.

In order to prevent the hooked headof the cartridge-extractorE, Fig.14,which is attached by means of its ring e to the rear of the breech center pieceB, from sliding off the cartridge-V rim in consequence of the longitudinal elastieity of the extractor, the following arrangement has been designed: The breech-bolthead cylinder A is surrounded directly behind the breech-bolt by the groove a', which is undercut, so that its upper edgeha-ngs over. (See Fig. 16.) The cartridge-extractor (see Fig. 13) is provided with a projection c', eor responding to the groove a. (See Fig. 13.) This projection is a little smaller than the groove, so that the cartridge-extractor E can move a little forward or backward, as required. When the cartridge is pushed into the barrel, the cartridge-extractor is thrown back. a little distance at the closure of the breech in consequence of its striking the cartridge-rim, and as in this ease its elasticity is not confined the hook of the cartridge-extractor is allowed to Slide over the cartridge-rim at the closing of the breech. A cartridge from the magazine is pushed forward by the cartridgeextractor as soon as the former leaves the magazine and also as soon as a cartridge is thrown into the loading-recess of the receiver for single-firing. Vhen the breech is opened, the breech-bolt recedes by itself at first, whereby the projection e is brought under the overhanging side wall of the groove a', thus taking away the elasticity of the cartridge-extractor. The more resistance the cartridge-case offers the less becomes the elasticity of the cartridge-extractor andthe stronger the grip of the latter on the rim.

By the continued and complete withdrawal of the breeclrbolt the ease is extracted from the receiver in the following manner: The space between the hook of the cartridge-extractor and the left wall of the receiver is much smaller than the rear diameter of the cartridge-ease, and therefore pushes elastically upon the base of the cartridge. As the cartridge-extractor at the Withdrawal of the I bolt has been sufficiently withdrawn to satisfy this tendency of the case the latter is thrown out completely from the receiver'. tridge-extractor of course does not join in the rotary movement of the breech-bolt, as it isl prevented from doing so by a corresponding groovein the receiver,which only allows its'lo'nlitud'inal forward-and backward movement.

The: cartridge-extractor therefore servesas a` guidel for the breech-bolt.

The iiring-springd and the rear end of thek firing-pin D are introduced-.into the breechboltcenter piece before lthe breech-bolt head` d is screwedV onto thek latter. The rear end of the firing-pin protrndes a considerabledistance backward out of the-.breech-bolt 'centerpiece sB; Onto this-.protrudingend is pushed the breech-bolt. rear piece C after the cartridge-A extractoi-.E has beenV pushed 'over-the, center piece xBby means of the ring e. By means of thefscrew-nnt c the firing-pin Dis connected to therear Lpiece C, so that these two pieces` opening and closingof the breech-bolt, the rear.

arm e2 of the cartridge-extractor (see Fig-17'),

reaches into the guiding-groove c in thel breech-bolt rear piece C, and as the cartridge-` extractor can only ,move forward and backward any rotary movem'entof the breech rear piece is prevented bythe extractor. At the moment of the complete-cocking,.with the breechbolt closed, the -projection c3 has just issued a little distance out of the slot inthe shoe, so that it may be turned round for locking. Before cocking the end oft-he arm e2 is at thev rear end of the groove c.-

As before described, the middle partof the cartridge-extractor E is formed as a ring e to surround the breech center piece B without interfering with the rotary movement of the latter. The protruding parts of the cartridgeextractor are placed partly in the right-hand breech-rib groove f7 of the shoe and partly into a separate groove fl. (See Fig. S.) Besides the cartridge-extractor rod E the cartridge-extractor ring e is supplied with a guiding-stud e3, (see Fig. 13,) which is, however, only of secondary importance and serves chieiiy as a stopper to the left-hand breechrib groove in the shoe,w hich otherwise would remain uncovered. assists to prevent aforward rotation of the cartridge-extractor. The rear end of the tiring-spring d (see Fig. 10) bears against the rear end of the breech-bolt center piece B, and thus always pushes the tiring-pin com-v pletel y forward, being prevented from further expansion by the firing-pin collar d2.

The .carsV Of course this stud also.

O-n the lower periphery of the breech-bolt head (see Fig.` 20) runswfromJ theA circular groove o the scar-groove a2 and in continuation of vit the groove b3 of the breech-bolt center piece which passes through the cartridgeextractor .ring e and finishes: at Vthe edge of the rear cylinder C of the 'breech-bolt center piece B. These three grooves thus connected form alongitudinal groove through the two forward breech-bolt parts and the ring e. This common groove serves for the reception of the .Sear Y72-which also limits the .backward movement of the'whole breech-bolt.l (See Fig. 3.) Vhen, then, the breech-bolt is pushedv forward, the rearlpiecev Gis kept back by the sear, the upper-backedge of thesearbeirfg slightly undercut-1.andengaging. ywith lthe cupped edge of c, thuscompressin g the ringspring.k This isreffected (seeFiglGz) because the firing-,pin D is kept back-while; the-breechbolt centerpiece B, during thecontinued forward and rotary movement, takes the rearipart of the firing-spring:forward,thefront part vof theiatterbeing keptin position by the firingpin 4collar d2.' Vhen, then, the trigger-ban H, Fig. 3, is pressed for the tiring of theriie at first when the. foreiinger is bent, the triggerbar` H. isv moved alone, while the spring is` somewhat pressed; butwhen theben'dingof thenger is continued the fore vrpart of thentrigger-.bar Hf presses down the scar h by engaging with the Sear-pin h. The breech-bolt rear piece C is thus freed from the sear 7L and is thrown vforward to the extent shown in Fig.

10 by means of the Yrapid expansion-ofthe ring-springd. To cock the breech-bolt in this-manner, it must be rotated to the right and lockedafter having been pushed forward, or the recoil of. the firing-spring will draw the bolt back again. handle b has been effected even in part, the compression of the spring by cooking or drawingback the rear portion C may be effected. If the handle b should not be completely Vhen this rotation of the IOO IOS

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turned, the Iinal locking of the breech-bolt is effectedas follows by means of the firingpin before the latter fires the cartridge. The firing-pin collar d2 has a projection forming a` segment of. a screw-thread, (see Fig. 16,) and inthe breech-bolt head A there is a screwlike recess .corresponding to the before-mentioned projection. When the breech is not completely closed, the said recess of the breech-bolt head A is not exactly opposite to the segmental screw projection d?, as in Fig. 1G. When the firing-pin isin this position and is thrown forward by the spring, it places the breech-bolt head A in a right position by means of the reaction of the said segmental screw projection and recess. During the opening of the breech when the bolt is rotated toward the left the firing-pin D- is pushed back by this device and the firingspring CZ is .thereby somewhat compressed. (See Fig. 3.) The complete compression of the firing spring d is effected when the breech-bolt is pushed forward and locked as described, the rear cylinder c being held back by the sear.

To prevent accidental firing of the loaded, cocked, and closed rifle, (particularly during any movement,) the breech-bolt rear piece C can be rotated to the left behind the receiver, thus arresting the firing-pin in all cases. For this purpose the breech-bolt rear piece C is provided with a projection c3, by means of which the former can be turned to the left (see Fig. 17) when the breech-bolt is cocked. The groove c runs into the transverse groove c2 (see Figs. 17 and 20) to admit of the piece C turning on the fixed extractor. On the rear end of the receiver (see Fig. 5) is, further, the oblique face f5, over which the projection c can slide to enter the recess f6. In this case firing is prevented and at the same time the breech-bolt is completely locked, which is effected in the following manner:

On the rear cylinder of the breech-bolt center piece Bis the separate longitudinal groove b4, which, when the breech has been completely closed, is situated directly opposite the sear h. (See Fig. 10.) When, however, the breech-bolt is cocked and the firing-pin arrested, as in Fig. 22, the sear h engages into this groove b4, and thus prevents the rotation of the breech-bolt and the opening of the breech as long as the firing-pin is cocked. Vhen the projection c8 is turned into its normal position, as in Fig. 12, the breech-bolt rear piece O, Fig. 22, presses at the same time the sear h down out of this groove tri-that is to say, by the pressure which the breech rear piece C can now effect against the oblique face h2 of the Sear 71. )Vhen the breech is completely closed, the firing-pin uncooked, and the firearm is not in use, Fig. 10, the sear engages into the groove c4 of the breechbolt rear piece C in order to reduce the compression of the trigger-spring h3. (See Fig. 10.) The handle b and its socket are turned to engage with the shoulder f2 of the receiver in the same manner as the three breech-ribs, before described, engage in their locking. (See Figs. 1 and 2.) The breech-bolt is thus locked twice. This second locking is,however, not real, because there is averysmall space between the socket of the handle and the shoulder f2 of the receiver. When the rifle has been used for a considerable time, this intermediate space will become less, as the breechbolt head A is bound to be upset in time in consequence of the high pressure of the gas. If this small intermediate space has become so much reduced that the rotation toward the left of the handle produces friction on the shoulderf2 of the receiver,it will be apparent to the rifleman that the breech-bolt head A must be exchanged for a new one. Nevertheless the handle is also available for safety-locking-that is to say, in case the breech-bolt head should be subjected to so heavy a strain that the breech-ribs a might break off by the gas-pressure. It is hardly necessary to take into consideration the possibility of this taking place, but if it were to happen the handle will stop the recoil of the breech-bolt.

The lower front corner of the magazine is reduced, as inv Fig. 1, to enable the bearer to shoulder the rifle conveniently. In order to have the lower surface of the magazine on one level with the lower surface of the trigger-guard G, the latter has been extended accordingly. The elliptical recess gis designed for the trigger-bar and the circular recess g for the magazine-catch I to allow of the latter being pressed back for lowering the magazine to enable the rifle to be used for single' loading. The duplicate trigger guard G, therefore, protects the magazine-catch from being pressed back accidentally.l The uniformity of these two lower surfaces of the trigger-guard and magazine further allows of the rifle being also shouldered at this place. To entirely disengage the magazine, the catch I should be pressed back into the guard by means of a thin packing piece or object beyond the position in which the catch comes flush with the guard when the bare finger only is used, as this latter position of catch merely allows the magazine to fall to its lower position without complete disengagement.

The rifle may also be used for single-loading by the two springs g2 being bent toward each other, and thus serving as a rest for the cartridges fed singly into the recess of the receiver. v

The front half ofthe cartridge-follower k, Fig. 42, is slit to allow of being removed from the magazine for cleaning when ordinarily the follower is kept back by the two lugs k3, Fig. 38, as its two elastic arms can be pressed together for this purpose.

Then the magazine has been emptied by repeated ring, the rear end of the cartridgefollower k, Fig. 39, rises so high that the breechbolt cannot be pushed forward. This serves as a signal to the ritieman that he must refill the magazine, or for single-firing he has to press the magazine-catch I to allow of the magazine being lowered. The catch I is always pressed forward by the spring t'. To insure the base of the magazine-spring 7o being perpendiculanto the longitudinal axis of the latter, a supporting-wedge slightly hollowed at one side is introduced on the bottom of the magazine.

For repeat-firing the filled magazine may be introduced from below, or if the empty or partially-empty magazine is already attached to the rifle single cartridges may be fed from above. The magazine can also be filled by packets by means of any suitable cartridgecramp.

I-Iaving fully described my invention, what I claim, and desire to secure by Letters Patent, is-

1. In a repeating ride with a cylindrical IOO breech-bolt A.` sear h, provided with undercut top edges and provided at the back edge with a second oblique face h2 of opposite direction, in combination with the recessed cupped edge of the firing-pin cylinder c and the groove h4 of the breech-bolt, so that in the securing of the lock by the Withdrawal and rotation of the iiring-pin and the action of the triggerspring the sear enters the groove b4 of the handle B to lock the breechbolt,while by the pressure of the readvanced ring-pin on the oblique face h2 the Sear is again automatically pressed down from the groove b4.

2. In a repeatingr rifle with a cylindrical breech-bolt A, cartridge-magazine, and a car- I5 KARL KRNKA.

Vitnesses:

RICHARD A. HOFFMANN, JOHN C. FELL.

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