US3789730A - Automatic weapon with self locking bolt breech block - Google Patents

Automatic weapon with self locking bolt breech block Download PDF

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Publication number
US3789730A
US3789730A US00174369A US3789730DA US3789730A US 3789730 A US3789730 A US 3789730A US 00174369 A US00174369 A US 00174369A US 3789730D A US3789730D A US 3789730DA US 3789730 A US3789730 A US 3789730A
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breech block
weapon
locking bolt
breech
cartridge
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Expired - Lifetime
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US00174369A
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A Helmes
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Rheinmetall Industrie AG
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Rheinmetall GmbH
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    • 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
    • F41A9/37—Feeding two or more kinds of ammunition to the same gun; Feeding from two sides
    • 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
    • F41A3/00—Breech mechanisms, e.g. locks
    • F41A3/12—Bolt action, i.e. the main breech opening movement being parallel to the barrel axis
    • F41A3/36—Semi-rigid bolt locks, i.e. having locking elements movably mounted on the bolt or on the barrel or breech housing
    • F41A3/38—Semi-rigid bolt locks, i.e. having locking elements movably mounted on the bolt or on the barrel or breech housing having rocking locking elements, e.g. pivoting levers or vanes
    • F41A3/40—Semi-rigid bolt locks, i.e. having locking elements movably mounted on the bolt or on the barrel or breech housing having rocking locking elements, e.g. pivoting levers or vanes mounted on the bolt

Definitions

  • An automatic weapon including a self locking bolt which comprises a weapon casing defining a loading chamber.
  • a breech block moves forwards and back and is adapted to insert a cartridge into the loading chamber during the forward movement of the breech block.
  • At least three laterally pivotable locking bolts are provided symmetrically to the longitudinal central axis of the breech block, for complete locking of the breech block against the weapon casing.
  • the present invention relates to an automatic weapon with self locking bolt breech block.
  • Breech blocks for automatic weapons in which the breech block is locked to the breech housing by means of pivotable locking bolts, are generally referred to as self locking bolt breech blocks.
  • the locking bolts are pivotally mounted at both sides in the breech block.
  • the locking bolts pivot outwardly and engage in appropriate recesses provided in the breech housing, in which case the forces acting on the breech block of the breech at the time of firing are transmitted by the locking bolts to the weapon or breech housing.
  • considerable surface pressure is applied to the support faces at the breech block and the breech housing.
  • a comparatively short recoil path for the breech block and a comparatively small recoil force of the breech block are desired.
  • the breech block should thus, on the one hand, be as short as possible and, on the other hand, should be kept as small as possible in lateral dimension. Further, a short recoil path for the breech block is very desirable, so that despite the desired high rate of fire the velocity of the breech block can be kept comparatively low, which, together with a short breech block enable a favorably low recoil force to be obtained.
  • the recoil path of the breech block is dependent both on the cartridge length and on the distance between the cartridge magazine and loading chamber. Thus, attempts are made to keep this distance as small as possible, in order to facilitate a rapid insertion of the cartridges, into the loading chamber.
  • one object of the present invention to provide an automatic weapon with a self locking bolt breech block which with the same or smaller dimensions relative to known breech blocks of this type, provides an increase in efficiency of the gun; in particular with comparatively small dimensions and low weight relative to customary locking bolt breech blocks, the breech block should facilitate a greater rate of fire and provide a capacity to withstand greater supporting forces.
  • this has the advantage that, with the same or even smaller width relative to the customary arrangement, the breech block can support greater forces and secondly, the centering of the breech block is improved. Therefore, without any danger of tilting, the breech block can be kept shorter, which in addition helps towards the desired reduction of the breech block weight despite an increase in efficiency.
  • one of the locking bolts is advantageously located in the vertical, longitudinal central plane of the gun, due to which the width of the breech block and the gun can be kept small.
  • two cartridge magazine devices can be brought close to the gun and to'the breech block by which means a rapid change from one type of ammunition to another is possible.
  • two apertures for the cartridge magazine are provided in the gun casing which seen in cross section are located respectively between two adjacent locking bolts.
  • FIG. 1 is a partial longitudinal section through the casing of an automatic weapon and the breech block
  • FIG. 2 is a cross-section along the lines II II of FIG. 1;
  • FIG. 3 is a cross-section along the lines III III of FIG. 1.
  • the weapon casing 1 is located a multi-part breech block 2, which moves back and forwards, and which for each forward movement inserts a cartridge into a loading chamber 3 of the gun.
  • the breech block is self locking and consists essentially of a breech head 4, a breech block body 5 and support flaps 6 and 6.
  • the breech head there are provided three locking bolts symmetrical to the longitudinal central axis of the breech block which are mounted to pivot radially in the breech head by means or semi-cylindrical support faces 7.
  • the breech block body 5 is connected to the breech head 4 to slide by the length s.
  • the locking breech block body lags behind the breech block head by the length s, the locking bolt 6 being pivoted, as shown in dot-dash lines in F IG; 1.
  • the locking bolts are pressed outwards by means of the inclined faces 9 provided on the following locking breech block body, by which means they enter the recesses 10 provided in the weapon casing and the breech block assumes the locked position according to FIG. 1.
  • the breech block 2 is guided in the weapon casing by means of guide faces 11 and 11 arranged in a circular arc, these guide faces being located radially to the locking bolts 6 and 6. Symmetrical to the vertical longitudinal central plane there are provided in the weapon casing in the region between two adjacent guide faces supply openings 12, 12 cartridges, in which the bodies 13, 13' of cartridge supply magazines engage. In order to be able to supply the cartridges as near as possible to the breech block 2, the latter has chord-like truncations 14, 14' in the peripheral region between the guide haces 11 and 11.
  • the cartridge supply magazines are pivotally connected to each other by a small amount, so that either a cartridge from the case 13 or the case 13 is gripped at will by the forward face of the counterrecoiling breech block head and is inserted into the loading chamber 3.
  • an extractor claw 15 is guided to move radially against the force of a spring 16.
  • the spring 16 consists of a closed spring ring (FIG. 2), which is arranged in a groove 16 located near the forward face of the breech head 4.
  • An automatic weapon including a self locking bolt comprising a weapon casing defining a loading chamber
  • breech block moving forwards and back and adapted to insert a cartridge into said loading chamber during the forward movement of said breech block
  • At least three laterally pivotable locking bolt means provided symmetrically to the longitudinal central axis of said breech block, for complete locking of said breechblock against said weapon casing,
  • one of said locking bolts is arranged in the vertical longitudinal central plane of said weapon casing,
  • said weapon casing has two apertures for receiving one end of each of said cartridge magazines,
  • each of said cartridge magazines is disposed between two adjacent locking bolt means.
  • An automatic weapon including a self locking bolt comprising a weapon casing defining a loading chamber,
  • breech block moving forwards and back and adapted to insert a cartridge into said loading chamber during the forward movement of said breech block
  • At least three laterally pivotable locking bolt means provided symmetrically to the longitudinal central axis of said breechblock, for complete locking of said breech block against said weapon casing,
  • said weapon casing includes guide faces constituting arcs of a circle in cross-section arranged around a closed sector thereof for guidance of said breech block during its forward and backward movement, and
  • said guide faces are provided radially to said locking bolt means
  • said breech block in cross section, has chord-like truncations between said guide faces.

Abstract

An automatic weapon including a self locking bolt which comprises a weapon casing defining a loading chamber. A breech block moves forwards and back and is adapted to insert a cartridge into the loading chamber during the forward movement of the breech block. At least three laterally pivotable locking bolts are provided symmetrically to the longitudinal central axis of the breech block, for complete locking of the breech block against the weapon casing.

Description

limited States Patent [1 1 Helmes AUTOMATIC WEAPON WITH SELF LOCKING BOLT BREECH BLOCK Alfred Helmes, Willich, Germany Rheinmetall GmbI-ll, Dusseldorf, Germany Filed: Aug. 24, 1971 Appl. No.: 174,369
Inventor:
Assignee:
Foreign Application Priority Data Sept. 11, 1970 Germany 2044964 US. Cl. 89/183, 42/25, 89/33 SF, 89/190 Int. Cl. F4ld 3/00, F4ld 9/02 Field of Search 42/25; 89/33 SF, 176, 182, 89/183, 190
References Cited UNITED STATES PATENTS Hampton 89/190 Feh.5,1974
2,948,195 8/1960 Linder 89/190 FOREIGN PATENTS OR APPLICATIONS 617,142 2/1949 Great Britain 42/25 12,181 1891 Great Britain 42/25 Primary ExaminerStephen C. Bentley Attorney, Agent, or FirmErnest G. Montague [5 7] ABSTRACT An automatic weapon including a self locking bolt which comprises a weapon casing defining a loading chamber. A breech block moves forwards and back and is adapted to insert a cartridge into the loading chamber during the forward movement of the breech block. At least three laterally pivotable locking bolts are provided symmetrically to the longitudinal central axis of the breech block, for complete locking of the breech block against the weapon casing.
2 Claims, 3 Drawing Figures I 3.7mm
PATENTEBHB 5 197 INVENTOR Mai/M IE E E AUTOMATIC WEAPON WITH SELF LOCKING BOLT BREECII BLOCK The present invention relates to an automatic weapon with self locking bolt breech block.
Breech blocks for automatic weapons, in which the breech block is locked to the breech housing by means of pivotable locking bolts, are generally referred to as self locking bolt breech blocks. In this case the locking bolts are pivotally mounted at both sides in the breech block. After the completed countercoil of the breech block, after it has inserted a cartridge in the loading chamber of the gun barrel, the locking bolts pivot outwardly and engage in appropriate recesses provided in the breech housing, in which case the forces acting on the breech block of the breech at the time of firing are transmitted by the locking bolts to the weapon or breech housing. Thus considerable surface pressure is applied to the support faces at the breech block and the breech housing.
In an effort to increase the efficiency of the guns and the ammunition, and in order to obtain as high as possible rate of fire, a comparatively short recoil path for the breech block and a comparatively small recoil force of the breech block are desired. The breech block should thus, on the one hand, be as short as possible and, on the other hand, should be kept as small as possible in lateral dimension. Further, a short recoil path for the breech block is very desirable, so that despite the desired high rate of fire the velocity of the breech block can be kept comparatively low, which, together with a short breech block enable a favorably low recoil force to be obtained. In addition, the recoil path of the breech block is dependent both on the cartridge length and on the distance between the cartridge magazine and loading chamber. Thus, attempts are made to keep this distance as small as possible, in order to facilitate a rapid insertion of the cartridges, into the loading chamber.
It is thus, one object of the present invention to provide an automatic weapon with a self locking bolt breech block which with the same or smaller dimensions relative to known breech blocks of this type, provides an increase in efficiency of the gun; in particular with comparatively small dimensions and low weight relative to customary locking bolt breech blocks, the breech block should facilitate a greater rate of fire and provide a capacity to withstand greater supporting forces.
It is another object of the present invention to provide an automatic weapon with self locking bolt breech block, wherein three locking bolts are provided symmetrically with respect to the longitudinal central axis of the breech block. Firstly, this has the advantage that, with the same or even smaller width relative to the customary arrangement, the breech block can support greater forces and secondly, the centering of the breech block is improved. Therefore, without any danger of tilting, the breech block can be kept shorter, which in addition helps towards the desired reduction of the breech block weight despite an increase in efficiency.
It is yet another object of the present invention to provide an automatic weapon with self locking bolt breech block, wherein one of the locking bolts is advantageously located in the vertical, longitudinal central plane of the gun, due to which the width of the breech block and the gun can be kept small. In this way, the requirements for a further advantageous embodiment of the invention are simultaneously provided, in that two cartridge magazine devices can be brought close to the gun and to'the breech block by which means a rapid change from one type of ammunition to another is possible. For this purpose two apertures for the cartridge magazine are provided in the gun casing which seen in cross section are located respectively between two adjacent locking bolts.
It is still another object of the present invention to provide an automatic weapon with self locking bolt breech block, wherein in order to achieve a good centering of the breech block and for the transmission of the supporting forces to the gun casing, it is also of advantage, if the breech block is guided in the breech housing by means of guide faces located around a closed sector and if these guide faces are located radially relative to the locking bolts.
It is a further object of the present invention to provide an automatic weapon with self locking bolt breech block, wherein in a further advantageous embodiment, seen in cross section the breech block has chordlike truncations between the guide faces. Due to this the magazines for supplying cartridges can be brought still nearer to the loading chamber, which, in accordance with the objects of the present invention, has a favorable effect on the dimensions of the breech block and on the breech block recoil path length.
It is still a further object of the present invention to provide an automatic weapon with self locking bolt breech block, wherein in addition, a further feature of the present invention contributes to keeping the length of the breech block as short as possible, in that the spring-loading of the ejector claw consists in known manner of a closed spring ring, which is inserted in an annular groove provided in the ejector claw and near the front face of the breech block. Due to this further cross sectional weakenings of the breech block head are avoided, which weakenings are present in many other arrangements extractor claws and their springloading arrangements.
With these and other objects in view, which will become apparent in the following detailed description, the present invention, which is shown by example only, will be clearly understood in connection with the accompanying drawing in which:
FIG. 1 is a partial longitudinal section through the casing of an automatic weapon and the breech block;
FIG. 2 is a cross-section along the lines II II of FIG. 1; and
FIG. 3 is a cross-section along the lines III III of FIG. 1.
Referring now to the drawing, the weapon casing 1 is located a multi-part breech block 2, which moves back and forwards, and which for each forward movement inserts a cartridge into a loading chamber 3 of the gun. The breech block is self locking and consists essentially of a breech head 4, a breech block body 5 and support flaps 6 and 6.
In the breech head there are provided three locking bolts symmetrical to the longitudinal central axis of the breech block which are mounted to pivot radially in the breech head by means or semi-cylindrical support faces 7. The breech block body 5 is connected to the breech head 4 to slide by the length s. During the forward movement of the breech block the locking breech block body lags behind the breech block head by the length s, the locking bolt 6 being pivoted, as shown in dot-dash lines in F IG; 1. After the insertion of a cartridge 8 into the loading chamber and as soon as the breech block head, has reached its forward position, the locking bolts are pressed outwards by means of the inclined faces 9 provided on the following locking breech block body, by which means they enter the recesses 10 provided in the weapon casing and the breech block assumes the locked position according to FIG. 1.
As can be seen from FIGS. 2 and 3, the breech block 2 is guided in the weapon casing by means of guide faces 11 and 11 arranged in a circular arc, these guide faces being located radially to the locking bolts 6 and 6. Symmetrical to the vertical longitudinal central plane there are provided in the weapon casing in the region between two adjacent guide faces supply openings 12, 12 cartridges, in which the bodies 13, 13' of cartridge supply magazines engage. In order to be able to supply the cartridges as near as possible to the breech block 2, the latter has chord-like truncations 14, 14' in the peripheral region between the guide haces 11 and 11. In the plane of the drawing the cartridge supply magazines are pivotally connected to each other by a small amount, so that either a cartridge from the case 13 or the case 13 is gripped at will by the forward face of the counterrecoiling breech block head and is inserted into the loading chamber 3. In the forward face of the breech head 4 an extractor claw 15 is guided to move radially against the force of a spring 16. The spring 16 consists of a closed spring ring (FIG. 2), which is arranged in a groove 16 located near the forward face of the breech head 4.
While I have disclosed one embodiment of the present invention, it is to be understood, that this embodiment is given by example only and not in a limiting sense.
I claim:
1. An automatic weapon including a self locking bolt comprising a weapon casing defining a loading chamber,
a breech block moving forwards and back and adapted to insert a cartridge into said loading chamber during the forward movement of said breech block,
at least three laterally pivotable locking bolt means provided symmetrically to the longitudinal central axis of said breech block, for complete locking of said breechblock against said weapon casing,
one of said locking bolts is arranged in the vertical longitudinal central plane of said weapon casing,
cartridge magazines,
said weapon casing has two apertures for receiving one end of each of said cartridge magazines,
the latter are arranged, in cross-section symmetrical with respect to the vertical longitudinal central plane of said weapon casing, and
each of said cartridge magazines is disposed between two adjacent locking bolt means.
a 2. An automatic weapon including a self locking bolt comprising a weapon casing defining a loading chamber,
a breech block moving forwards and back and adapted to insert a cartridge into said loading chamber during the forward movement of said breech block,
at least three laterally pivotable locking bolt means provided symmetrically to the longitudinal central axis of said breechblock, for complete locking of said breech block against said weapon casing,
said weapon casing includes guide faces constituting arcs of a circle in cross-section arranged around a closed sector thereof for guidance of said breech block during its forward and backward movement, and
said guide faces are provided radially to said locking bolt means, and
said breech block, in cross section, has chord-like truncations between said guide faces.

Claims (2)

1. An automatic weapon including a self locking bolt comprising a weapon casing defining a loading chamber, a breech block moving forwards and back and adapted to insert a cartridge into said loading chamber during the forward movement of said breech block, at least three laterally pivotable locking bolt means provided symmetrically to the longitudinal central axis of said breech block, for complete locking of said breechblock against said weapon casing, one of said locking bolts is arranged in the vertical longitudinal central plane of said weapon casing, cartridge magazines, said weapon casing has two apertures for receiving one end of each of said cartridge magazines, the latter are arranged, in cross-section symmetrical with respect to the vertical longitudinal central plane of said weapon casing, and each of said cartridge magazines is disposed between two adjacent locking bolt means.
2. An automatic weapon including a self locking bolt comprising a weapon casing defining a loading chamber, a breech block moving forwards and back and adapted to insert a cartridge into said loading chamber during the forward movement of said breech block, at least three laterally pivotable locking bolt means provided symmetrically to the longitudinal central axis of said breechblock, for complete locking of said breech block against said weapon casing, said weapon casing includes guide faces constituting arcs of a circle in cross-section arranged around a closed sector thereof for guidance of said breech block during its forward and backward movement, and said guide faces are provided radially to said locking bolt means, and said breech block, in cross section, has chord-like truncations between said guide faces.
US00174369A 1970-09-11 1971-08-24 Automatic weapon with self locking bolt breech block Expired - Lifetime US3789730A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2044964A DE2044964C3 (en) 1970-09-11 1970-09-11 Automatic rapid fire weapon with support bolt lock

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US3789730A true US3789730A (en) 1974-02-05

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CH (1) CH524801A (en)
DE (1) DE2044964C3 (en)
FR (1) FR2107438A5 (en)
GB (1) GB1338897A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4119012A (en) * 1975-10-18 1978-10-10 Rheinmetall Gmbh Double-feed sprocket arrangement for munition changing
US7107715B2 (en) 2003-05-23 2006-09-19 Ra Brands, L.L.C. Bolt assembly with locking system
US8733009B2 (en) 2012-01-06 2014-05-27 Ra Brands, L.L.C. Magazine cutoff
US8800422B2 (en) 2012-08-20 2014-08-12 Ra Brands, L.L.C. Bolt assembly for firearms
US9417019B2 (en) 2012-08-24 2016-08-16 Ra Brands, L.L.C. Fire control for auto-loading shotgun

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3045831C2 (en) * 1980-12-05 1984-06-14 Mauser-Werke Oberndorf Gmbh, 7238 Oberndorf Support flap for a rigidly closing breech of automatic firearms
ITRM20130425A1 (en) * 2013-07-18 2015-01-19 Piergiorgio Cataldi RESET MECHANISM FOR SEMIAUTOMATIC HUNTING AND / OR SHOOTING WEAPONS

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB617142A (en) * 1945-09-21 1949-02-01 Zbrojovka Brno Np Improvements connected with breech bolts for small arms and cartridge extractor actuating springs therefor
US2861374A (en) * 1957-02-01 1958-11-25 Samuel L Hampton Slide bolt action for firearms
US2948195A (en) * 1957-02-07 1960-08-09 Mach Tool Works Oerlikon Admin Breech mechanism for automatic firearms

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB617142A (en) * 1945-09-21 1949-02-01 Zbrojovka Brno Np Improvements connected with breech bolts for small arms and cartridge extractor actuating springs therefor
US2861374A (en) * 1957-02-01 1958-11-25 Samuel L Hampton Slide bolt action for firearms
US2948195A (en) * 1957-02-07 1960-08-09 Mach Tool Works Oerlikon Admin Breech mechanism for automatic firearms

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4119012A (en) * 1975-10-18 1978-10-10 Rheinmetall Gmbh Double-feed sprocket arrangement for munition changing
US7107715B2 (en) 2003-05-23 2006-09-19 Ra Brands, L.L.C. Bolt assembly with locking system
US20070107290A1 (en) * 2003-05-23 2007-05-17 Ra Brands, L.L.C. Bolt assembly with locking system
US7219461B1 (en) 2003-05-23 2007-05-22 Ra Brands, L.L.C. Bolt assembly with locking system
US8733009B2 (en) 2012-01-06 2014-05-27 Ra Brands, L.L.C. Magazine cutoff
US8800422B2 (en) 2012-08-20 2014-08-12 Ra Brands, L.L.C. Bolt assembly for firearms
US9417019B2 (en) 2012-08-24 2016-08-16 Ra Brands, L.L.C. Fire control for auto-loading shotgun

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Publication number Publication date
DE2044964B2 (en) 1975-03-06
GB1338897A (en) 1973-11-28
CH524801A (en) 1972-06-30
DE2044964A1 (en) 1972-03-16
DE2044964C3 (en) 1975-10-23
FR2107438A5 (en) 1972-05-05

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