US3140554A - Double, tandem-arranged magnazine feeding device - Google Patents
Double, tandem-arranged magnazine feeding device Download PDFInfo
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- US3140554A US3140554A US286874A US28687463A US3140554A US 3140554 A US3140554 A US 3140554A US 286874 A US286874 A US 286874A US 28687463 A US28687463 A US 28687463A US 3140554 A US3140554 A US 3140554A
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- Prior art keywords
- magazine
- cartridges
- magazines
- cartridge
- bolt
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- Expired - Lifetime
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- 230000000994 depressogenic effect Effects 0.000 description 5
- 238000006073 displacement reaction Methods 0.000 description 3
- 238000010304 firing Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 108010082357 dividin Proteins 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F41—WEAPONS
- F41A—FUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
- F41A9/00—Feeding or loading of ammunition; Magazines; Guiding means for the extracting of cartridges
- F41A9/61—Magazines
- F41A9/64—Magazines for unbelted ammunition
- F41A9/65—Box magazines having a cartridge follower
- F41A9/68—Plural magazines, e.g. tandem magazines ; Arrangements of cartridges in two or more independent rows or channels which are selectively or sequentially brought into operative position
Definitions
- This invention relates to feeding devices for firearms and more particularly to feeding devices which include firearm mounted magazines.
- the simplest means for increasing the supply of cartridges is to increase the length of the column of cartridg% in the magazine but this increases the length of the magazine and the length to which a magazine can be increased is limited, especially those for military firearms in which bulk is very important.
- the length and the tension of the magazine spring which biases the cartridges to the stripping position must be increased accordingly. This produces problems as the increased tension of the spring increases the force with which the leading cartridge is pressed against the magazine lips when positioned for stripping. Because of this force, the energy in the reciprocating bolt must be increased sufiiciently to overcome the additional force required to strip the leading cartridge from the magazine during counterrecoil travel and in some firearms such increased energy is not available for the bolt.
- FIG. 1 is a longitudinally cross-sectioned view of a firearm showing the cartridges fed from the front magazine with the cartridges in the rear magazine being held in reserve by being depressed by the depressor out of contact by the feed pawl on the bolt;
- FIG. 2 is a fragmentary view similar to FIG. 1 but shows the cartridges fed from the secondary, reserve magazine, with one of the cartridges intermediately positioned in the forward magazine in transfer to the barrel chamber;
- FIG. 3 is a view similar to FIG. 2 but shows a cartridge positioned between the rear and front magazines during transfer therebetween;
- FIG. 4 is a view taken along line 4-4 of FIG. 1;
- FIG. 5 is a view taken along line 55 of FIG. 1;
- FIG. 6 is a View taken along line 6-6 of FIG. 2;
- FIG. 7 is a view taken along line 77 of FIG. 2.
- Bolt assembly 18 is of conventional two-piece type and comprises a carrier 20 and a bolt 22 which is disposed for telescopic and rotational displacement relative thereto for locking purposes and which is provided with a cylindrical head 24.
- a spring-pressed feed pawl 26 is mounted on the underside of carrier 20 at the rear end thereof.
- a magazine housing 30 depends from receiver 16 adjacent the rear end thereof and such housing includes a rear and a front channel, noted at 32 and 34 respectively, each of which receives a magazine 36.
- Magazine 36 is of conventional two-stack type, with cartridges 38 being arranged alternately therein in a right-hand stack and a left-hand stack. Magazine 36 includes a follower 40 pressed upwardly within a case 42 by a spring 44 and a tang 45 which extends from the follower through a suitable opening therefor in the rear end of the case.
- a pair of arcuate lips 46 extends upwardly and inwardly from opposite sides of case 42 to form a longitudinal opening 48 through which feed pawl 26, or a segment of head 24, may extend for successively stripping cartridges 38 from the right and left-hand stacks in magazine 36.
- Lips 46 and follower 40 are designed so that the leading cartridges 38 in magazine 36 is held in a stripping po sition between the follower and the one of the lips: which is on the side which corresponds to the stack in which the leading cartridge is located.
- cartridges 38 are alternately located in a stripping position against the righthand and the left-hand one of the lips 46.
- Lips 46 are designed to hold th stripping position cartridge so that the long axis thereof is normal to the long axis of magazine 36.
- Rear channel 32 is formed so that, when magazine 36 is received therein, the long axes of cartridges 38 therein are parallel to the long axis of receiver 16.
- Front channel 34 is formed so that, when magazine 36 is received thereby, the long axes of cartridges 38 therein are tilted approximately 3 toward the chamber of barrel 14.
- a pair of latches 50 are pivotally mounted on magazine housing 30 so as to be respectively actuatable against the magazines 36 in front channel 34 and rear channel 32 for releasably securing the magazines therein.
- cartridges 38 are first picked up and chambered by bolt assembly 18 from magazine 36 in front channel 34 and then, when that magazine is emptied, the cartridges in the rear magazine are automatically made available.
- a depressor 52 which is pivotally mounted in rear channel 32 so as to be contactable with the base of the leading cartridge 38 in magazine 36 therein when the magazine is pressed upwardly into the channel and so as to depress the cartridge sufficiently to be positioned away from contact by feed pawl 26 when the magazine continues to be pushed upwardly to the latched position.
- Depressor 52 is biased to the cartridge contacting position by a spring-biased plunger 54 and is actuated to release the contacted cartridge 38, as shown in FIG.
- Lever 56 which, when pivoted against the depressor, causes the depressor to slip over the end of the contacted cartridge for release thereof to the stripping position.
- Lever 56 is pivotally depressed by tang 45 of magazine 36 in front channel 34 and they are arranged so that, when the next to the last cartridge 38 is elevated to the stripping position, the tang presses upwardly against the lever to rock the lever against depressor 52, whereby the depressor is actuated to release the cartridges in the magazine in rear channel 32.
- cartridge 38 When cartridge 38 is picked up by feed pawl 26, it is moved longitudinally from the rear to the front'magazine 36 because of the guiding contact of the cartridge with the underside of carrier as is best shown in FIG. 3.
- the ogive of the cartridge projectile cammingly depresses follower 40 of the front magazine while being moved thereinto.
- cartridge 38 in front magazine 36 is elevated to the stripping position by spring 44 after head 24 passes by the cartridge and thereby the cartridge is ready for pickup by the head during the following counterrecoil stroke of bolt assembly 18.
- a feeding device including a magazine housing depending from the receiver adjacent the rear end thereof, a magazine for releasably holding a supply of cartridges spring-biased to a stripping position, means in said housing for receiving a pair of said magazines tandemwise in a front and a rear position respectively, means for starting transfer of the cartridges from the rear one of said magazines to the barrel without interruption of feeding when the front one of said magazines is emptied, a head of said bolt disposed at the front end thereof in cooperation'with the front one of said magazines for successively stripping the cartridges therefrom, and a feed pawl mounted on the rear end of the bolt for cooperation with the rear one of said magazines for successively stripping the cartridges therefrom.
- the feeding device as defined in claim 1 including a depressor arranged for holding the cartridges in the rear one of said magazines depressed and out of contact by said feed pawl, and a lever operationally disposed between said depressor and a spring-biased follower in the front oneof said magazines for actuating said depressor to release the cartridges in the rear one of said magazines when the next to the last one of the cartridges in the front one of said magazines is raised to the stripping position by said follower therein.
- said magazine includes a spring-biased follower arranged so that said follower in the front one of said magazines is depressed by the cartridge transferred from the rear to the front one of said magazines and so as to elevate the cartridge into stripping position for transfer contact by said head when said head is displaced clear thereof in recoil travel of the bolt.
Description
July 14, 1964 R. H. COLBY 3,140,554
DOUBLE, TANDEMARRANGED MAGAZINE FEEDING DEVICE Filed June 10, 1963' 2 Sheets-Sheet l INVENTOR. Ri chnrcf H. Bunny Q M S a w I WM aWS.
R. H. COLBY July 14, 1964 DOUBLE, TANDEM-ARRANGED MAGAZINE FEEDING DEVICE 2 Sheets-Sheet 2 Filed June 10, 1963 as J 5 r 7 4 ..I a j P An 1 5 a o 3 2 2 INVENTOR. Hi uhnrcI H- Eulb ALN M- The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.
This invention relates to feeding devices for firearms and more particularly to feeding devices which include firearm mounted magazines.
With shoulder arms which are designed for military use, it is important to have as large a supply of cartridges as possible available in the weapon magazine so that firing during a critical period need not be interrupted for magazine replacement or replenishment. Obviously, the simplest means for increasing the supply of cartridges is to increase the length of the column of cartridg% in the magazine but this increases the length of the magazine and the length to which a magazine can be increased is limited, especially those for military firearms in which bulk is very important. Moreover, by increasing the length of the column of cartridges, the length and the tension of the magazine spring which biases the cartridges to the stripping position must be increased accordingly. This produces problems as the increased tension of the spring increases the force with which the leading cartridge is pressed against the magazine lips when positioned for stripping. Because of this force, the energy in the reciprocating bolt must be increased sufiiciently to overcome the additional force required to strip the leading cartridge from the magazine during counterrecoil travel and in some firearms such increased energy is not available for the bolt.
Attempts have been made in the past to overcome these problems by dividin'g'box-type magazines into two compartments and designing the feeding system so that the cartridges are fed from the second compartment after the first compartment is emptied, thereby reducing the length of the magazine and the length and tension required of the magazine spring. But these designs have not been completely successful because in all of them firing has to be interrupted while feeding is transferred from one compartment to another or else the length of the firearm receiver and, consequently, the overall length of the firearm must be increased to permit sufficient overtravel of the bolt to chamber cartridges from both the primary and reserve magazine supply.
It is one object of this invention to provide for firearms a feeding device in which a secondary reserve supply of cartridges is automatically made available when the primary source of cartridges is depleted.
It is a further object of this invention to provide such a feeding device in which two similar magazines are mounted in the firearm in tandem arrangement with the front magazine providing the primary supply of cartridges and the rear magazine the secondary, reserve supply.
It is another object of this invention to provide such a feeding device wherein the cartridges are transferred from the front magazine into the barrel by the bolt head and, when the primary supply is depleted, the cartridges in the rear magazine are successively transferred from the rear magazine to the front magazine by a feed pawl on the bolt and are transferred from the front magazine to the barrel chamber by the bolt head during the subsequent counterrecoil travel of the bolt.
3,i4,554 Patented July 14, 1964 It is still another object of this invention to provide such a feeding device in which the feeding pawl is mounted on the reciprocating bolt at the rear end thereof to reduce the length of the firearm receiver by eliminating bolt overtravel.
It is another and further object of this invention to provide a feeding device which is simple but rugged in construction and is positive in operation.
The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:
FIG. 1 is a longitudinally cross-sectioned view of a firearm showing the cartridges fed from the front magazine with the cartridges in the rear magazine being held in reserve by being depressed by the depressor out of contact by the feed pawl on the bolt;
FIG. 2 is a fragmentary view similar to FIG. 1 but shows the cartridges fed from the secondary, reserve magazine, with one of the cartridges intermediately positioned in the forward magazine in transfer to the barrel chamber;
FIG. 3 is a view similar to FIG. 2 but shows a cartridge positioned between the rear and front magazines during transfer therebetween;
FIG. 4 is a view taken along line 4-4 of FIG. 1;
FIG. 5 is a view taken along line 55 of FIG. 1;
FIG. 6 is a View taken along line 6-6 of FIG. 2; and
FIG. 7 is a view taken along line 77 of FIG. 2.
Shown in the figures is a rifle 12 having a barrel 14 and a receiver 16 in which a bolt assembly 18 is disposed for longitudinal reciprocation between a battery and a recoil position. Bolt assembly 18 is of conventional two-piece type and comprises a carrier 20 and a bolt 22 which is disposed for telescopic and rotational displacement relative thereto for locking purposes and which is provided with a cylindrical head 24. A spring-pressed feed pawl 26 is mounted on the underside of carrier 20 at the rear end thereof.
A magazine housing 30 depends from receiver 16 adjacent the rear end thereof and such housing includes a rear and a front channel, noted at 32 and 34 respectively, each of which receives a magazine 36. Magazine 36 is of conventional two-stack type, with cartridges 38 being arranged alternately therein in a right-hand stack and a left-hand stack. Magazine 36 includes a follower 40 pressed upwardly within a case 42 by a spring 44 and a tang 45 which extends from the follower through a suitable opening therefor in the rear end of the case.
A pair of arcuate lips 46 extends upwardly and inwardly from opposite sides of case 42 to form a longitudinal opening 48 through which feed pawl 26, or a segment of head 24, may extend for successively stripping cartridges 38 from the right and left-hand stacks in magazine 36. Lips 46 and follower 40 are designed so that the leading cartridges 38 in magazine 36 is held in a stripping po sition between the follower and the one of the lips: which is on the side which corresponds to the stack in which the leading cartridge is located. Thus, cartridges 38 are alternately located in a stripping position against the righthand and the left-hand one of the lips 46.
As will be explained hereinafter, cartridges 38 are first picked up and chambered by bolt assembly 18 from magazine 36 in front channel 34 and then, when that magazine is emptied, the cartridges in the rear magazine are automatically made available. This is accomplished by a depressor 52 which is pivotally mounted in rear channel 32 so as to be contactable with the base of the leading cartridge 38 in magazine 36 therein when the magazine is pressed upwardly into the channel and so as to depress the cartridge sufficiently to be positioned away from contact by feed pawl 26 when the magazine continues to be pushed upwardly to the latched position. Depressor 52 is biased to the cartridge contacting position by a spring-biased plunger 54 and is actuated to release the contacted cartridge 38, as shown in FIG. 3, by a lever 56 which, when pivoted against the depressor, causes the depressor to slip over the end of the contacted cartridge for release thereof to the stripping position. Lever 56 is pivotally depressed by tang 45 of magazine 36 in front channel 34 and they are arranged so that, when the next to the last cartridge 38 is elevated to the stripping position, the tang presses upwardly against the lever to rock the lever against depressor 52, whereby the depressor is actuated to release the cartridges in the magazine in rear channel 32.
Thus, When a magazine 36 is latched in front channel 34 and another magazine 36 is latched in rear channel 32, rifle 12 is loaded. During firing, cartridges 38 in front magazine 36 are stripped therefrom by head 24 and chambered in barrel 14 during counterrecoil movement of bolt assembly 18 to battery position. During cyclic reciprocation of bolt assembly 18, when feeding from the front magazin 36, cartridges 38 in the rear magazine are held depressed by depressor 52 away from contact by feed pawl 26 as it moves along opening 48.
When the next to the last cartridge 38 is elevated to a stripping position in front magazine 36, tang 45, in such front magazine, contacts lever 56 causing displacement thereof against depressor 52 which is pivotally rocked to slip over the base of the leading one of the cartridges in the rear magazine. When the leading cartridge 38 in rear magazine 36 is freed, it pops up to the stripping position against the corresponding one of the lips 46 by the bias of spring 44 and is ready to be picked up by feed pawl 26 during the next displacement of bolt assembly 18 to battery position. Cartridge 38 is transferred from the rear magazine 36 into the magazine in front channel 34 ready for pickup by head 24 during the next operating cycle of firearm 12.
When cartridge 38 is picked up by feed pawl 26, it is moved longitudinally from the rear to the front'magazine 36 because of the guiding contact of the cartridge with the underside of carrier as is best shown in FIG. 3. When cartridge 38 enters front magazine 36, the ogive of the cartridge projectile cammingly depresses follower 40 of the front magazine while being moved thereinto. During the recoil stroke of bolt assembly 18, cartridge 38 in front magazine 36 is elevated to the stripping position by spring 44 after head 24 passes by the cartridge and thereby the cartridge is ready for pickup by the head during the following counterrecoil stroke of bolt assembly 18.
Although a particular embodiment of the invention has been described in detail herein, it is evident that many variations may be devised within the spirit and scope thereof and the following claims 'are intended to include such variations.
I claim:
1. In a firearm including a barrel and a receiver with a bolt disposed for reciprocation therein in recoil and counterrecoil strokes, a feeding device including a magazine housing depending from the receiver adjacent the rear end thereof, a magazine for releasably holding a supply of cartridges spring-biased to a stripping position, means in said housing for receiving a pair of said magazines tandemwise in a front and a rear position respectively, means for starting transfer of the cartridges from the rear one of said magazines to the barrel without interruption of feeding when the front one of said magazines is emptied, a head of said bolt disposed at the front end thereof in cooperation'with the front one of said magazines for successively stripping the cartridges therefrom, and a feed pawl mounted on the rear end of the bolt for cooperation with the rear one of said magazines for successively stripping the cartridges therefrom.
2. The feeding device as defined in claim 1 including a depressor arranged for holding the cartridges in the rear one of said magazines depressed and out of contact by said feed pawl, and a lever operationally disposed between said depressor and a spring-biased follower in the front oneof said magazines for actuating said depressor to release the cartridges in the rear one of said magazines when the next to the last one of the cartridges in the front one of said magazines is raised to the stripping position by said follower therein.
3. The feeding device as defined in claim 1 wherein said feed'pawl, the reciprocal travel of the bolt and the tandem relationship of said magazines are arranged in cooperation so that the cartridges are transferred by said feed pawl from the rear to the front one of said magazines during counterrecoil travel of the bolt and are transferred by said head from the front one of said magazines into the barrel during the next counterrecoil travel of the bolt.
4. The feeding device as defined in claim 3 wherein said magazine includes a spring-biased follower arranged so that said follower in the front one of said magazines is depressed by the cartridge transferred from the rear to the front one of said magazines and so as to elevate the cartridge into stripping position for transfer contact by said head when said head is displaced clear thereof in recoil travel of the bolt.
References Cited in the file of this patent UNITED STATES PATENTS 1,709,399 Herlach et al. Apr. 16, 1929 2,391,756 Vesely Dec. 25, 1945 2,399,900 Vesely May 7, 1946
Claims (1)
1. IN A FIREARM INCLUDING A BARREL AND A RECEIVER WITH A BOLT DISPOSED FOR RECIPROCATION THEREIN IN RECOIL AND COUNTERRECOIL STROKES, A FEEDING DEVICE INCLUDING A MAGAZINE HOUSING DEPENDING FROM THE RECEIVER ADJACENT THE REAR END THEREOF, A MAGAZINE FOR RELEASABLY HOLDING A SUPPLY OF CARTRIDGES SPRING-BIASED TO A STRIPPING POSITION, MEANS IN SAID HOUSING FOR RECEIVING A PAIR OF SAID MAGAZINES TANDEMWISE IN A FRONT AND A REAR POSITION RESPECTIVELY, MEANS FOR STARTING TRANSFER OF THE CARTRIDGES FROM
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US286874A US3140554A (en) | 1963-06-10 | 1963-06-10 | Double, tandem-arranged magnazine feeding device |
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Application Number | Priority Date | Filing Date | Title |
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US286874A US3140554A (en) | 1963-06-10 | 1963-06-10 | Double, tandem-arranged magnazine feeding device |
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US3140554A true US3140554A (en) | 1964-07-14 |
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US286874A Expired - Lifetime US3140554A (en) | 1963-06-10 | 1963-06-10 | Double, tandem-arranged magnazine feeding device |
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3196568A (en) * | 1964-01-07 | 1965-07-27 | Frederick P Reed | Switching device for a tandem-type magazine feeding system |
US20060180134A1 (en) * | 2005-02-11 | 2006-08-17 | Illuzzi Louis M | Combination solid projectile and paintball gun, and solid projectile adapter for paintball gun |
RU2519571C1 (en) * | 2012-12-25 | 2014-06-20 | Николай Евгеньевич Староверов | Automatic arms - 4 /versions/ |
RU2553536C1 (en) * | 2013-12-18 | 2015-06-20 | Николай Евгеньевич Староверов | Automatic weapon-9 (versions) |
RU2576853C1 (en) * | 2015-01-12 | 2016-03-10 | Николай Евгеньевич Староверов | Small arms-2 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1709399A (en) * | 1926-04-28 | 1929-04-16 | Rheinische Metallw & Maschf | Automatic firearm |
US2391756A (en) * | 1940-12-31 | 1945-12-25 | Vesely Josef | Magazine for firearms |
US2399900A (en) * | 1942-08-14 | 1946-05-07 | Vesely Josef | Firearm |
-
1963
- 1963-06-10 US US286874A patent/US3140554A/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1709399A (en) * | 1926-04-28 | 1929-04-16 | Rheinische Metallw & Maschf | Automatic firearm |
US2391756A (en) * | 1940-12-31 | 1945-12-25 | Vesely Josef | Magazine for firearms |
US2399900A (en) * | 1942-08-14 | 1946-05-07 | Vesely Josef | Firearm |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3196568A (en) * | 1964-01-07 | 1965-07-27 | Frederick P Reed | Switching device for a tandem-type magazine feeding system |
US20060180134A1 (en) * | 2005-02-11 | 2006-08-17 | Illuzzi Louis M | Combination solid projectile and paintball gun, and solid projectile adapter for paintball gun |
RU2519571C1 (en) * | 2012-12-25 | 2014-06-20 | Николай Евгеньевич Староверов | Automatic arms - 4 /versions/ |
RU2553536C1 (en) * | 2013-12-18 | 2015-06-20 | Николай Евгеньевич Староверов | Automatic weapon-9 (versions) |
RU2576853C1 (en) * | 2015-01-12 | 2016-03-10 | Николай Евгеньевич Староверов | Small arms-2 |
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