Repeating Firearm With Bolt-open Latch

Abstract

A bolt-open latch for a repeating firearm having a cartridge-carrier or a lifter for transferring cartridges from the magazine to the cartridge chamber. The bolt-open latch is actuated by movement of the lifter beyond its cartridge-feeding position when no cartridge is transferred by the lifter during a loading cycle, so that the breech-bolt is held in its retracted position by the bolt-open latch when the last round in the magazine has been fired.

Description

The invention relates to firearms, and it relates more particularly to firearms of the repeating type, such as automatic or semi-automatic rifles and shotguns in which it is desired to automatically hold the breech-bolt open after the last round has been expended.

Various means are now employed in automatic firearms for achieving this result. In automatic shotguns, for example, which have a tubular magazine and a cartridge-carrier for lifting the cartridges from the magazine to the barrel, the bolt is held open when the magazine is empty by latching the carrier while the bolt is retracted so that the carrier can not move. Since the bolt can not return to close the breech unless the carrier is free to move, the bolt is locked in its open or retracted position when the carrier is latched. The Winchester 1400 and Remington 1100 operate in this manner, but these guns use the cartridge extractor or a cartridge-actuated latch on the carrier to block movement of the carrier when the magazine is empty.

In guns which use box magazines, the cartridge follower in the magazine is sometimes provided with a projection which extends into the path of the bolt after the last round has been fired, thereby latching the bolt in a retracted position. Military rifles, for example, are usually provided with a bolt-open stop of this type. To my knowledge, no tubular-magazine sporting rifles have a bolt-open latch which operates automatically. Some have a device for holding the bolt in its open position, but the latch must be operated manually, and the bolt must be retracted by hand when the gun is empty in order to hold the bolt in its retracted position.

An object of the present invention is to provide an automatic firearm, which uses a cartridge carrier or lifter, with a bolt-open latch which operates automatically when the gun is empty on retraction of the bolt in order to hold the bolt open. For firearms that use a carrier for transferring the cartridges from the magazine to a position in which they can be fed into the chamber of the gun, the cartridge is lifted by the carrier against fixed guide-means or cartridge retaining lips where it is in position to be moved endwise into the chamber, usually by the breech-bolt as it travels forward on closing. If there is no cartridge for the carrier to move into position against the cartridge feeding guide-means, the carrier travels a short distance beyond the position at which it is stopped when a cartridge is being loaded into the chamber.

To my knowledge no guns up to now have utilized the additional movement of the cartridge carrier or lifter, which occurs only when the gun is empty, for initiating operation of a bolt-open latch.

The present invention resides in providing a bolt-open latch which becomes operable by movement of the cartridge carrier beyond its cartridge-feeding position, in order to latch the breech-bolt in an open position when no cartridge is available to be fed into the chamber. Any suitable latch-means may be employed which is effective in retaining the bolt in a retracted position. For example, a stop-lever may be used which is pivoted into the path of the bolt when the carrier moves beyond its cartridge-feeding position or if desired, the carrier may be latched in its fully elevated position so that the bolt is prevented from closing.

These and other embodiments of the invention will become more apparent from the following description of specific ways in which to carry out the invention.

FIG. 1 is a fragmentary side elevational view of the action of a firearm embodying the invention, portions being shown broken away and in section and showing the breech-bolt closed with a second cartridge ready to be moved into cartridge-feeding position as soon as the one in the chamber is fired;

FIG. 2 is a vertical cross-section of the firearm action shown in FIG. 1 taken on the line 2--2, but with the receiver removed;

FIG. 3 is a view similar to FIG. 1, but showing the bolt in a retracted position about to pick up the second cartridge and to feed it into the chamber, and omitting the portions of the barrel and receiver shown in FIG. 1;

FIG. 4 is a view of the opposite side of the action as shown in FIG. 3;

FIG. 5 is a top plan view of the firearm action of FIGS. 1-4 with the breech-bolt removed;

FIG. 6 is a view similar to FIG. 4, but showing the bolt in its fully retracted position and about to be latched open by the bolt-open latch;

FIG. 7 is a view similar to FIG. 3, but showing the parts in the position they assume when the bolt is latched open; and

FIG. 8 is a view similar to FIG. 6 of a modification of the bolt-open latch illustrated in FIGS. 4 and 6.

In the specific embodiments of the invention shown in the drawings, the breech-bolt 10 reciprocates within the receiver of the gun between its forward position (FIG. 1) where it is in closing relation with the breech of the barrel 12, and its fully retracted position where the rear of bolt engages a fixed abutment 14 on the receiver. The bolt 10 is guided in the usual manner by engagement with the inner walls of the receiver and is supported on its underside by a mounting plate 16, in which the firing and trigger mechanisms are mounted, and from the underside of which the trigger guard 18 projects. In this instance bolt 10 is actuated for reloading the gun by the firing of a cartridge C.sup.1 in the chamber, the rearward force of which is exerted on the bolt, imparting sufficient energy to the bolt so that it is driven rearward against the abutment 14. A bolt-return spring 19, which is compressed between bolt 10 and abutment 14, drives the bolt forward on the return stroke. During the rearward movement of bolt 10, the hammer 20 is pivoted into cocking relation with the sear 22 which is actuated by the trigger 24 for firing the gun.

The cartridges are transferred from a tubular magazine 26, which extends parallel to and below the barrel 12, to the feeding position in which the cartridge C.sup.2 is shown in FIGS. 3, and 4 by means of a lifter or carrier 28. In this particular case, the carrier 28 is continuously urged by a coil spring 30 for pivotal movement in a clockwise direction (as viewed FIGS. 1 and 3) about its pivot pin 32, which is supported in the mounting plate 16. As will be described hereinafter, carrier 28 is pivoted in the opposite direction into a cartridge-receiving position upon movement of the bolt 10 forward into battery position. Carrier 28, which in this instance is a thin elongated member, extends forward or to the left as shown in FIG. 1 between a pair of guide-plates 34,34 having grooves 36 and 38 on their facing sides to form feed-passages through which the cartridges move from the magazine 26 to the position from which they are fed into the chamber. Grooves 36 slope upwardly from the rear end of magazine 26 in order to guide the cartridges onto the upper edge 39 of carrier 28 and against a stop 40 which positions each cartridge for transfer upward from its position shown in FIG. 1 to its feeding position substantially as shown in FIGS. 3 and 4.

As the bolt is retracted, carrier 28 is pivoted upward by its spring 30, lifting the cartridge upward until its upper surface comes into contact with a pair of inwardly extending guide-lips 42,42 along the top edges of guide-plates 34,34. Carrier 28, being spring-loaded toward its upper limit of travel, resiliently presses the cartridge against guide-lips 42,42 and holds it in this position as the bolt 10 continues to travel rearward into contact with stop 14 and is then driven forward by the return spring 19 to battery position. During the return stroke, the lower corner of bolt 10 at its front end engages the rear of the cartridge C.sup.2, driving it forward into the chamber of the barrel 12. As the cartridge is fed forward in this manner, it is held by the upward resilient force of carrier 28 and by the fixed guide-means of guide-lips 42,42 along which the rim of the cartridge slides. The combined action of the forward movement of bolt 10 and the upward urging of carrier 28 causes the rim of the cartridge to slide upward within a vertical recess in the face of the bolt as the cartridge is being driven forward. Just before the nose of the bullet enters the chamber in barrel 12, the rim of the cartridge is released by guide-lips 42,42 and the carrier 28 presses it up behind the extractor claws 44,44 of bolt 10, which grip the rim evenly at both sides and guide the cartridge straight into the chamber.

The rear end of cartridge-carrier 28 is provided with a rectangular notch or recess 46, within which fits a laterally extending finger 48 formed on the rearward end of a carrier-actuating lever 50 (FIG. 4), which extends parallel to the cartridge-carrier 28 within an elongated recess 52 in the outer surface of a side wall 51 of mounting plate 16. Lever 50 is privoted near its mid-point on a pivot pin 54, which is fixed in the side wall of the mounting plate 16, and an opening 49 is provided in the side wall 51 through which finger 48 extends into engagement with cartridge-carrier 28. The upper edge 56 of the forward end of lever 50 slopes upwardly into the path of breech-bolt 10, so that when the breech-bolt moves forward into battery position, it engages the forward end of lever 50 depressing it in a clockwise direction as viewed in FIG. 4, thereby raising the finger 48 at its rear end and pivoting carrier 28 in the same direction, or counter-clockwise as viewed from the opposite side of FIG. 3, into cartridge-receiving position against the pressure of spring 30.

Cartridges that have been loaded into magazine 26 are urged rearwardly onto carrier 28 by an elongated coil spring 60 having a cartridge follower 62 which presses rearwardly against the nose of the last cartridge in the magazine. As each cartridge is received by the carrier 28 and lifted into feeding position, the next cartridge in line is prevented from moving onto the carrier by the front edge 64 of the carrier, thereby preventing the cartridges from interfering with the operation of the carrier. As illustrated in FIG. 1, when the last cartridge C.sup.2 is fed onto the carrier 28, the follower 62 projects into the feed passage 36, maintaining contact with cartridge C.sup.2 and pressing it rearwardly into engagement with stop 40 of the cartridge-carrier.

It should be noted here that when the carrier 28 is in the position shown in FIG. 1 with its upper edge 39 aligned with the bottom of feed-passage 36, carrier 28 is in its "cartridge-receiving" position. On the other hand, when carrier 28 moves from its cartridge-receiving position to lift a cartridge upward against the guide-lips 42,42, as illustrated in FIGS. 3 and 4, the carrier is in its "cartridge-feeding" position.

Now, when the last cartridge C.sup.2 has been fired, breech-bolt 10 is retracted in the usual manner as if in reloading. Rearward travel of the breech-bolt out of engagement with the upper surface 56 of carrier-actuating lever 50 permits the carrier 28 to swing upward as if to transfer another cartridge into feeding position. However, since the magazine is empty, no cartridge is transferred by the carrier 28 which, therefore, moves upward under the urge of its lifting spring 30 to released upper limit of movement shown in FIGS. 6 and 7, which is beyond its cartridge-feeding position (FIG. 3). This last increment of movement of carrier 28 beyond its cartridge-feeding position is of course necessary in order to ensure continuous engagement of a cartridge with guide-lips 42,42 when the cartridge is being fed into the chamber. It is well known, moreover, that such additional movement of the carrier is also necessary in order to ensure that it presses the rim of the cartridge up behind the extractor claws 44,44 when the cartridge, on being driven forward by the breech-bolt, is releases by guide-lips 42,42.

As is clearly seen by comparing the position of carrier 28 (FIG. 3) in its cartridge-feeding position with the position (FIG. 7) to which it is moved when the gun is empty, carrier 28 moves a significant distance beyond its cartridge-feeding position whenever the bolt is retracted while the gun is empty. This of course is due to the fact that no cartridge is present on the carrier to prevent it from moving upward beyond the cartridge-feeding position, such additional upward movement being limited by engagement of the finger 48 on carrier-actuating lever 50 with the bottom of the rectangular opening 49 in the mounting plate 16, through which it extends, as best seen in FIGS. 4, 6 and 7.

Referring now more particularly to FIGS. 4 and 6, a pivoted bolt-open latch 64 is disposed on the same side of the mounting plate 16 as the carrier-actuating lever 50 and is disposed co-extensively therewith in the same plane. Bolt-open latch 64 is an elongated member that is pivoted near its mid-point on a pivot pin 66. One end 68 of latch 64 extends rearward and upwardly for latching engagement within a notch 70 in the lower side of breech-bolt 10 when the bolt is retracted and when the bolt-open latch 64 is pivoted clockwise into its latching position as shown in FIG. 6. The other end 72 of latch 64 extends forward and downward through an opening in the bottom of mounting plate 16 for manipulation by the shooter in order to release breech-bolt 10 once it has been latched open.

The upper edge 78 of the forward end 72 of bolt-open stop 64 is shaped for engagement with, and actuation by, a rounded engagement lug 80 on the underside of carrier-actuating lever 50 adjacent its actuating finger 48. As hereinbefore mentioned, when breech-bolt 10 is forward with its underside engaging the upper edge 56 of lever 50, the latter is pivoted clockwise (as viewed in FIGS. 4 and 6) raising the finger 48 at its other end in order to pivot carrier 28 in the same direction into its cartridge-receiving position. At the same time the lug 80 on the under side of lever 50 is lifted completely out of engagement with the surface 78 of bolt-open latch 64. However, upon retraction of bolt 10 out of engagement with the cam surface 56 of lever 50, the forward portion of carrier 28 is pivoted upward by the lifting spring 30, thus lowering the rear, notched side of the cartridge-carrier and moving the finger 48 and lug 80 of carrier-actuating lever 50 downward toward the surface 78 of the bolt-open latch 64.

If during this movement of the cartridge-carrier and actuating lever, a cartridge is in the process of being lifted from the magazine by the carrier 28 to its feeding position under the guide-lips 42,42 of guide-plates 34,34, the carrier pivots to its cartridge-feeding position -- see FIG. 4 wherein cartridge C.sup.2 is shown in feeding position preventing the carrier from moving upward beyond this position. At this point the lug 80 on actuating lever 50 is just at the point of engaging the bolt-open latch 64 without actually actuating it. However, when the magazine is empty and no cartridge is disposed on the carrier to be fed into the chamber, carrier 28 moves beyond its cartridge-feeding position until the finger 48 of the actuating lever 50 engages the bottom of the elongated opening 49 in the mounting plate 16. This additional movement of the carrier 28 moves the lug 80 of the actuating lever downward against the surface 78 of bolt-open latch 64 and pivots its rear end 68 upward into its latching position (FIG. 6). Since at this point the bolt 10 is fully retracted, the stop-surface at the rear end 68 of latch 64 moves into the notch 70 on the under side of the bolt, so that the breech-bolt is held at the start of its return stroke by engagement of the stop-surface 68 of the bolt-open latch with the back edge of breech-bolt notch 70. In order to close the action, the breech-bolt is readily released by manually raising the finger portion 72 of the latch 64, thereby lowering its stop-surface 68 out of the notch 70.

It will be noted that in the particular arrangement shown in FIGS. 4 and 6, the interconnection between the cartridge-carrier and the bolt-open latch 64 is provided through engagement in only one direction of the lug 80 with the surface 78 of the bolt-open latch 64 and that lug 80 moves completely out of contact with latch 64 when the action is closed. In order to prevent the latch 64 from accidentally moving into latching relationship with the breech-bolt before the magazine is empty, a wire spring 82 is provided above latch 64 so that it bears downward against the upper edge of the latch rearward of pivot pin 66 so that the latch is continuously urged toward its inoperative position. Thus, latch 64 will move into latching relation with breech-bolt 10 only when the cartridge-carrier 28 pivots beyond its cartridge-feeding position causing lug 80 to engage the surface 78 of the latch and to pivot it into its latching position against the force of spring 82.

FIG. 8 shows a highly desirable modification of the bolt-open latch of FIGS. 1-7, in which the latch is moved positively by the carrier-actuating lever both out of latching position as well as into latching position, thereby eliminating the need for the wire spring 82 and positively preventing accidental latching of the breech-bolt 10 as long as at least one cartridge remains in the magazine. To this end, the portion of bolt-open latch 64', which is engaged by the carrier-actuating lever 50' is formed with a notch 78' into which the rear end of the lever 50' fits, so that each movement of lever 50' causes latch 64' to pivot a corresponding amount in the opposite direction. A carrier-engaging finger corresponding to the finger 48 of the previously described embodiment, extends laterally from the rear end of lever 50' into operative engagement with the carrier 28, so that upon retraction of bolt 10 carrier 28 is pivoted upward by its lifting spring when the breech-bolt moves out of engagement with lever 50'. This causes lever 50' to pivot counterclockwise with carrier 28, lowering its rear end and simultaneously pivoting latch 64' clockwise. As in the previously described embodiment of the invention, retraction of the breech-bolt when the magazine is empty causes carrier 28 to pivot upward to the limit of it movement in that direction. Bolt-open latch 64' is thus pivoted far enough for its rear end to engage the notch 70 in breech-bolt 10, thereby latching the bolt open. However, if at least one cartridge remains in the magazine, it is moved by the magazine follower 62 onto the carrier 28, which is accordingly prevented from pivoting to the limit of its counter-clockwise movement, as viewed in FIG. 8, by engagement of the cartridge with the cartridge guide-lips 42,42. The bolt-open latch 64', therefore, can not pivot into latching relation with the breech-bolt due to the fact that the cartridge prevents the carrier 28 from moving beyond its cartridge-feeding position so that the rear end of latch 64' is not moved up into its latching position. Consequently, the only time that the bolt-open latch can operate is when there is no cartridge available to be transferred into feeding position by the carrier 28.

Claims

What is claimed is:

1. In a repeating firearm having a barrel, a breech-bolt reciprocable into and out of closing relationship with the breech of the barrel, a magazine, a mounting plate, a cartridge-carrier movable between predetermined limits upon reciprocation of the breech-bolt for transferring cartridges from the magazine to a cartridge-feeding position from which they are fed into the breech of the barrel and fixed guide-means against which each cartridge is urged when in its cartridge-feeding position by said cartridge-carrier, said cartridge-carrier being disposed at one of its limits of travel in a cartridge-receiving position with respect to the magazine and in a cartridge-feeding position while urging a cartridge against said guide-means, said cartridge-feeding position of said cartridge-carrier being intermediate the limits of travel of the cartridge-carrier such that on retraction of said breech-bolt when no cartridge has been fed from the magazine, said cartridge-carrier is movable to its other limit of travel beyond said cartridge-feeding position; the improvement comprising in combination with said cartridge-carrier and breech-bolt of a bolt-open latch supported on said mounting plate for movement into a latching position for blocking the retracted breech-bolt against returning to its breech-closing position, and means for moving said bolt-open latch into said latching position following movement of said cartridge-carrier beyond said cartridge-feeding position in the direction of its said other limit of travel.

2. The combination defined in claim 1, wherein said bolt-open latch has a stop-surface normally disposed outside the path of reciprocal movement of said breech-bolt, said means for moving said bolt-open latch including means interconnecting said cartridge-carrier and bolt-open latch for positioning said stop-surface in the path of said breech-bolt.

3. The combination defined in claim 2, which includes a carrier-actuating member mounted on said mounting plate and having a first portion engageable by said breech-bolt and a second portion engageable with said cartridge-carrier, said carrier-actuating member being movable upon reciprocation of said breech-bolt for actuating said cartridge-carrier, and said means interconnecting said cartridge-carrier and bolt-open latch comprise a portion of at least one of said carrier-actuating member and cartridge-carrier disposed for engagement with said bolt-open latch during said movement of the cartridge-carrier beyond said cartridge-feeding position for moving said stop-surface into the path of said breech-bolt.

4. The combination defined in claim 3, wherein said means interconnecting said cartridge-carrier and bolt-open stop comprises a portion of said carrier-actuating member.

5. The combination defined in claim 4, wherein said cartridge-carrier and carrier-actuating member are each elongated members pivotally mounted intermediate their ends, on said mounting plate, said first and second portions of said carrier-actuating member comprising the opposite ends thereof with said second portion connected to one end of said cartridge-carrier, the portion of said cartridge-carrier on the opposite side of its pivot point from said one end being adapted and arranged to receive the cartridges and to move them consecutively into said cartridge-feeding position, said means interconnecting said cartridge-carrier and bolt-open latch including said second end portion of said carrier-actuating member.

6. The combination defined in claim 5, wherein said bolt-open latch is also an elongated member pivoted between its ends with one of its ends disposed for engagement by said carrier-actuating member and the other end forming said stop-surface.

7. The combination defined in claim 6, wherein said cartridge-carrier and carrier-actuating member are disposed parallel to each other and pivot together in the same direction, said bolt-open latch being disposed in substantially the same plane as said carrier-actuating member and co-extensive therewith along the path of movement of said breech-bolt, such that said breech-bolt engages said first portion of said carrier-actuating member during the latter portion of its return stroke in order to move said cartridge-carrier into its cartridge-receiving position, said stop-surface on said bolt-open latch being disposed adjacent a portion of said breech-bolt, when the breech-bolt is retracted, for engagement therewith when no cartridge is fed to the chamber.

8. The combination defined in claim 7, wherein said means interconnecting said carrier-actuating member and bolt-open latch actuate said bolt-open latch only on movement of said cartridge-carrier beyond said cartridge-feeding position, said bolt-open latch being spring-loaded out of latching relationship with said breech-bolt.

9. The combination defined in claim 7, wherein said means interconnecting said cartridge-carrier and bolt-open latch also include a recess in said one end of said cartridge-carrier into which fits said second end portion of said carrier-actuating member for positively moving said bolt-open latch into and out of latching relation with said breech-bolt.

10. The combination defined in claim 3, wherein said cartridge-carrier and carrier-actuating member are each elongated members pivotally mounted intermediate their ends on said mounting plate, said first and second portion of said carrier-actuating member comprising the opposite ends thereof with said second end portion engageable with one end of said cartridge-carrier, the portion of said cartridge-carrier on the opposite side of its pivot point from said one end being adapted and arranged to receive the cartridges and to move them consecutively into said cartridge-feeding position.

11. The combination defined in claim 10, wherein said bolt-open latch is also an elongated member pivoted between its ends with one of its ends disposed for engagement by said interconnecting means and the other end forming said stop-surface.