Patent Publication Number: US-4646458-A

Title: Rimless cartridge extractor

Description:
BACKGROUND OF THE INVENTION 
     This invention relates in general to firearms and deals more particularly with improved rimless cartridge extractor mechanism. 
     The extractor mechanism for removing a rimless cartridge from the cartridge chamber of a firearm usually includes an extractor element for engaging the cartridge within an annular extraction groove formed in the cartridge case and spaced from the end of the case. In a relatively large firearm it is usually possible to provide an extractor mechanism having an extractor element capable of sufficient movement to fully withdraw an associated cartridge from the cartridge chamber of the firearm. However, in a small handgun it is often not possible to provide the degree of extractor element movement required to effect full cartridge extraction. In such a firearm it may be necessary to provide a means for disengaging the extractor element from a partially extracted cartridge to enable the partially withdrawn cartridge to be dumped or manually removed from the cartridge chamber. The present invention is concerned with this problem. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention a firearm for firing rimless cartridges has an extractor mounted in a laterally outwardly opening slot formed in one side of the firearm. The extractor engages an extraction groove in a rimless cartridge contained within a cartridge chamber of the firearm and is movable rearwardly relative to the cartridge chamber to effect partial extraction of the cartridge. The extractor is further supported for lateral movement out of engagement with the extraction groove when the cartridge is in a partially extracted position to release the cartridge and permit it to be dumped or otherwise removed from the cartridge chamber. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a side elevational view of a firearm having an extractor mechanism embodying the present invention. 
     FIG. 2 is similar to FIG. 1 but shows the firearm in a loading/unloading position. 
     FIG. 3 is a fragmentary exploded perspective view of the firearm shown in FIGS. 1 and 2. 
     FIG. 4 is a somewhat enlarged perspective view of the extractor. 
     FIG. 5 is a somewhat enlarged fragmentary sectional view taken along the line 5--5 of FIG. 1. 
     FIG. 6 is a somewhat enlarged side elevational view of the extractor element. 
     FIG. 7 is a left end elevational view of the extractor element as it appears in FIG. 6. 
     FIG. 8 is a right elevational view of the extractor element as it appears in FIG. 6. 
     FIG. 9 is a plan view of the extractor element. 
     FIG. 10 is a sectional view of the extractor element taken along the line 10--10 of FIG. 1. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     The extractor mechanism of the present invention, indicated generally at 10, is illustrated and described with reference to a small handgun or derringer designated generally by the reference numeral 12. The illustrated gun 12 is conventional in most respects, consequently only those parts of the gun necessary to a complete understanding of the invention are hereinafter described. 
     The gun 12 has a frame 14 which defines a receiver 15. A barrel designated generally by the numeral 16 is secured to the frame by a pivot pin 18 for pivotal movement relative to the frame between closed or firing position and an open or loading/unloading position, as will be hereinafter further described. Preferably, and as shown, the barrel 16 has a generally rectangular cross-section and includes parallel bores 20, 20 arranged in over and under relationship to each other. Each bore 20 has a cartridge chamber 22 which opens through the breech end of the barrel for receiving a rimless cartridge. A generally U-shaped locking band or strap 24, pivotally supported on the breech end of the barrel, carries a depending locking finger 36 and in a locking position engages an upwardly extending locking projection on the receiver indicated at 26 to releasably retain the barrel in its closed position. 
     A pair of firing pins (not shown) are supported within the receiver 15. Each firing pin is aligned in a firing position with an associated cartridge chamber 22 when the barrel is locked in its closed position. The firing mechanism (not shown) is generally conventional and includes a hammer which sequentially strikes the firing pins to fire a cartridge seated in each of the cartridge chambers (One such cartridge C is shown in FIG. 5). 
     Considering now the extractor mechanism in further detail, the illustrated extractor mechanism 10 is particulary adapted to simultaneously extract two cartridge cases C, C from the firing chambers 22, 22 and has a generally T-shaped extractor element 28, best shown in FIGS. 4-10, which includes a central leg 30 and a cross member 32. The extractor element extractor is received within a generally complimentary T-shaped slot 33 which opens laterally outwardly through one side and through the breech end of the barrel. The elongated central leg 30 has a generally V-shaped cross section which generally complements an associated portion of the slot 33. The extractor element 28 is supported by walls for smooth forward and rearward sliding movement relative to the barrel. A notch 34 formed in the leg 30 opens laterally outwardly and receives the operating finger 36 therein. A longitudinally extending and a laterally opening groove 38 formed in the leg 32 communicates with the notch 34 and receives an elongated resilient spring wire member 40 therein. A portion of the spring wire member 40 disposed within the notch 34 is outwardly bowed in the direction of the operating finger 36 and bears against the inner side of the operating finger for a purpose which will be hereinafter evident. The integral cross member 32 is disposed within the rearwardly opening portion of the slot 33 at the breech end of the barrel. The inner edges of the cross member 32 project for some distance into the cartridge chambers 22, 22 and to a ready position when the barrel is locked in its closed position and are shaped to engage annular grooves in two rimless cartridges C, C seated in the chambers 22, 22. A forwardly facing inner edge of the cross member 32 is slightly chamfered as indicated at 42, and best shown in FIG. 5 and 9. 
     To load the firearm 12 the rear end portion of the locking strap 24 is raised a sufficient distance to clear the locking projection 26 on the receiver. The barrel is then tilted to its open position to expose the ends of the cartridge chambers 22, 22 to receive cartridges. Two rimless cartridges are then inserted into the chambers. The arrangement of the spring 40 within the notch 34 allows some limited lateral outward movement of the extractor element 28 relative to the barrel 16 to permit cartridges C, C to be inserted into the cartridge chambers 22, 22. The tapered noses of the cartridge exert a camming action upon the extractor cross member 32 to move it laterally outward and away from the cartridge chambers 22, 22 as the cartridges are inserted into the chambers. When the cartridges are fully seated within the chambers the inner edges of the cross member 32 are biased into engagement with the cartridges C, C within the extraction grooves therein by biasing force exerted by the bowed portion of the spring 40 acting upon the inner surface of the operating finger 36. The barrel may then be pivoted to its closed position after which the locking strap 24 is engaged with the locking projection 26 to lock the barrel in its firing position. 
     After the gun has been fired the spent cartridge shells are extracted by releasing the locking strap 24 and tilting the barrel to its loading/unloading position. The locking strap is moved a sufficient distance in a counterclockwise direction from its position of FIG. 1 to its position of FIG. 2 to bring the operating finger 36 into engagement with a forwardly facing abutment surface which defines the rear of the notch 34 to cam the extractor element 28 rearward to an extracting position which partially withdraws the spent carriages C, C from the cartridge chambers. Thereafter, slight movement of the cross member 32 in a laterally outward direction causes the front end portion of the leg 30 to pivot on the inner surface of the groove 38 and allows the cross number 32 to move out of engagement with the extraction grooves in the cartridges C, C whereupon the spent cartridges may be dumped or otherwise manually removed from the cartridge chambers. The cross number 32 may be easily moved out of holding engagement with the cartridges by engaging a thumbnail with the rear inner edge of the cross member and pulling the cross number in a laterally outward direction.