US3711983A

US3711983A - Autoloading firearm

Info

Publication number: US3711983A
Application number: US00151694A
Authority: US
Inventors: H Allyn
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-01-21
Filing date: 1971-06-10
Publication date: 1973-01-23
Anticipated expiration: 1990-01-23

Abstract

An autoloading firearm of the blowback type wherein the assembled components are brought into operative relationship by the tightening of an assembly screw at final assembly.

Description

United States Patent [191 [111 3,71 1,983 Allyn [451 Jan. 23, 1973 AUTOLOADING FIREARM [56] References Cited Inventor: Harold D. Allyn, Garfield Street, Springfield, Mass. 01 108 2,765,563 10/1956 Roper et al. ..42/75 C [22] Filed: June 10, 1971 [21] Appl. No.: 151,694 Primary ExaminerStephen C. Bentley Attorney-Kenwood Ross and Chester E. Flavin Related U.S. Application Data [63] Continuation-impart of Ser. No. 792,694, Jan. 21, [57] ABSTRACT 1969' 3584533 An autoloading firearm of the blowback type wherein the assembled components are brought into operative [52] U.S. Cl. ..42/75 C relationship by the tightening of an assembly Screw at [51] Int. Cl. ..F41c 23/00 fina assembly [58] Field of Search ..42/18 R, 75 C 4 Claims, 43 Drawing Figures PATENTEDJin 2 3 F975 SHEET 1 OF 5 YNVENTOR.

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HAROLD D. ALLYN BY firm/00d @014 AUTOLOADING FIREARM The application is a continuation-in-part of my application, Ser. No. 792,694 filed Jan. 21, 1969, now US. Pat. No. 3,584,533.

The invention teaches a firearm in which the components and certain surfaces thereof are brought into operative operation as a takedown screw is tightened, all so that various loosely-assembled parts, including the barrel in the receiver, are locked together to form a completely assembled firearm upon final assembly.

Additionally, the invention features a magazine housing having an integral feed ramp and barrel alignment surface and a rearwardly extending arcuate lug or lugs for embracing the walls of the receiver and the cam lug or lugs.

The invention also features a bedding plate having a forwardly facing lower bedding surface, a forwardly facing stop surface and a rearward lower can surface and rear bifurcated portions.

In the drawings:

FIG. 1 is a fragmentary sectional view, in side elevation, of the firearm in closed ready-to-fire position;

FIG. 2 is a fragmentary view, in side elevation, partly in section, of the firearm immediately following release of the hammer by the sear;

FIG. 3 is a fragmentary sectional view, in side elevation, showing the firearm at the moment of firing;

FIG. 4 is a view, similar to FIG. 3, showing the firearm in full recoil position;

FIG. 5 is a view, similar to FIG. 4, showing the firearm immediately prior to the release of the trigger forwardly;

FIG. 6 is a partial view, in bottom plan, of the rear portion of the receiver, showing the sear block portion of an alternate form of safety in fire position;

FIG. 7 is a partial view, in top plan, of the rear end of the receiver, showing the thumb piece of the FIG. 6 form of safety in safe position;

FIG. 8 is a partial view, in side elevation, of the rear end of the receiver, showing the sear block portion of the FIG. 6 form of safety in safe position;

FIGS. 9 and 10 are views, in rear and side elevation respectively, of the recoil spring washer;

FIG. 1 1 is a view, in bottom plan, of the extractor;

FIG. 12 is a view, in side elevation, of the recoil spring guide;

FIG. 13 is a view on line l3-13 ofFIG. 12;

FIG. 14 is a partial sectional view of the front portion of the breech bolt, as viewed from the top;

FIG. 15 is a view, in rear elevation, showing the firing mechanism removed from the stock and the triggersear pin in place;

FIG. 16 is a view, in section, on line l616 of FIG.

1, showing the trigger-sear pin retained by the stock;

FIG. 17 is a view, in section, on line l7-17 of FIG.

FIG. 18 is a view in section, on line l818 of FIG. 2;

FIG. 19 is a view in section, on line 19-19 of FIG. 38;

FIG. 20 is a view, in section, on line 20-20 of FIG. 38;

FIGS. 21 and 22 are views, in rear and side elevation respectively, of the sear;

FIGS. 23 and 24 are views, in rear and side elevation respectively, of the magazine housing;

FIGS. 25 and 26 are views, in side and front elevation respectively, of the take down cam;

FIGS. 27 and 28 are views, in rear and side elevation respectively, of the trigger;

FIG. 29 is a partial view, inside elevation, of the front portion of an alternate form of trigger;

FIGS. 30 and 31 are views, in side and front elevation respectively, of the takedown lug;

FIG. 32 is a view, in bottom plan, of the receiver;

FIG. 33 is a schematic view of the assembly locking means;

FIGS. 34 and 35 are views, in side and front elevation respectively, of the magazine catch and ejector;

FIGS. 36 and 37 are partial views, in rear and side elevation respectively, of the magazine showing the magazine retaining lug;

FIG. 38 is a vertical longitudinal sectional view of the bedding plate and associated components;

FIGS. 39 and 40 are views, in top plan and elevation respectively, of the bedding plate;

FIG. 41 is a partial view, in top plan of the rear portion of the mechanism, showing the safety;

FIG. 42 is a view in side elevation of the rear portion of the mechanism, showing the safety and trigger-sear pin; and

FIG. 43 is a fragmentary sectional view, in side elevation, partly in section, of an alternate form of the lug and feed ramp of the magazine housing.

The firearm includes a stock 2, a trigger guard 3, a fore end 4, a butt stock 6, a barrel 8, and a receiver 9, as shown in FIG. 1, and a sear 10 (best shown in FIGS. 21 and 22), a trigger 11 (best shown in FIGS. 27 and 28), and a safety 13 and trigger sear pin 12 (best shown in FIG. 42).

A centrally-located longitudinally-extending slot in the lower portion of receiver 9 accommodates sear 10, and an adjoining longitudinally-extending slot, best seen in FIG. 32 which is a bottom plan view of the receiver, accommodates trigger 11.

A laterally-extending trigger-sear pin 12, extended through aligned openings in receiver 9 and trigger 11 and sear 10 and safety 13, retains these components in proper relative positions. With respect to sear l0 and safety 13, the aligned openings comprise elongated horizontally-extending

slots

14 and 15 respectively.

The rear of receiver 9 has a vertically-disposed longitudinally-extending fiat face. Safety 13, positioned thereadjacent, is retained by a spiral portion 16 of trigger-sear pin 12. See FIGS. 15 and 16.

Spiral portion 16 provides a detent tension for the safety and also bears upon the inner wall of stock 2 to preclude lateral movement of the trigger-sear pin. And as shown in FIG. 41, spiral portion 16 has a retaining bend l7 receivable in an opening 118 in the safety.

Due to elongated slot 15 in safety 13, a spring tension urges the safety forwardly and allows a detent portion 19 of the safety to operate within vertically-disposed detent slots in the receiver rear.

A forwardly-extending sear block portion 20 of safety 13 is located downwardly ofa thumb piece 21 so that, with the detent portion of the safety located in a left-hand or fire detent notch in receiver 9, the sear block portion is disposed adjacent the left-hand side of the sear to allow free vertical movement of its rearward end. With detent portion 19 in a right-hand or safe detent notch, the sear block portion is interposed between a horizontal flat portion of the receiver and the extreme upper rear portion of the sear to prevent sear vertical movement and preclude gun discharge.

A protrusion between the fire and safe detent notches in the receiver allows safety detent portion 19 to pass thereover owing to elongated slot and also to the resilience of a spiral coil adjacent the forward portion of the safety. A shoulder on the outboard side of each of the fire and safe detent notches retains thumb piece 21 within the confines of the detent notches, when the safety is thrown.

With the firearm in uncocked position, safety 13 cannot be thrown from fire to safe position.

Safety 13, shown in fire position in FIGS. 2-5, cannot be thrown to safe position, the extreme upper rear portion of sear 10 being in a rearward position blocking lateral movement of the forward end of sear block portion of the safety.

When a breech bolt 22 is in closed, hammer-cocked position, and when trigger 11 is released forwardly (FIG. 1), sear 10 is in forward position and safety 13 is free to be moved from fire to safe position, enabling the operator to determine the cocked or uncocked condition ofa hammer 24.

Receiver 9 has a centrally-located longitudinally-extending front opening to allow the breech bolt and hammer to reciprocate freely therein, with the rearward face of the hammer contacting a recoil surface 26 of the receiver upon termination of the recoil stroke. See FIG. 4. Rearwardly and centrally of this front opening, a second opening of reduced size freely accommodates a hammer spring 28. Rearwardly and centrally of this second opening, a third opening of reduced size freely houses a recoil spring 30 embracing a recoil spring guide 32.

An alternate form of trigger 11a is shown in FIG. 29 wherein a hook 100 may be provided so that the upper inside portion 102 of the hook may replace upper horizontal surface 56 of the trigger as the means for arresting unwanted forward movement of the finger portion of the trigger.

An alternate form of safety is shown in FIGS. 6-8. The rear portion of receiver 9 is shown in bottom plan view in FIG. 6 with the modified safety in tire position, the finger portion of the trigger held to the rear and the mechanism in the full recoil position as shown in FIG. 4. Here the safety has been combined with a modified form of trigger-sear pin 120, the pin having a safety portion 13a which includes a sear block portion 20a and a thumb piece portion 21a aligned thereabove. A loop 16a replaces spiral 16 of the first described trigger-sear pin 12 and supplies the desired forward detent tension. In such modification, trigger-sear pin 12a extends through receiver 9 in a manner similar to the preferred form of trigger-sear pin and the verticallydisposed longitudinally-extending flat portion on the rear end of the receiver may be eliminated accordingly.

Thumb piece portion 21a is shown in safe position in FIG. 7 and sear block portion 20a is shown in safe position in FIG. 8 wherein the mechanism is in the boltclosed hammer-cocked position as shown in FIG. 1.

In FIG. 12, recoil spring guide 32 is seen to terminate rearwardly in an enlarged portion. The front end of the enlarged portion serves as a recoil spring shoulder and its extreme rear end is configured to contact an upwardly-extending rearward portion 34 of sear 10.

The forwardly-facing surface of portion 34 is inclined to provide a camming action and in urging the rear end of the sear downwardly and conjointly, a

pivoting action at trigger-sear pin 12 urges the sear front end upwardly. These joint camming and pivoting actions enable recoil spring 30 through recoil spring guide 32, to provide an upward urging of the front end of scar 10 to cause a sear point to pivot in a sear notch in hammer 24.

The forward end of recoil spring 30 seats in a recoil spring washer 36 (FIGS. 9 and 10), which washer is receivable in an opening in the rear end of breech bolt 22.

The sides of the forward portion of recoil spring guide 32 (FIGS. 12 and 13), rearwardly ofa full diameter forward retaining end, are flattened to allow passage through a slot in recoil spring washer 36 as the breech bolt recoils rearwardly.

Hammer spring 28, circumscribing recoil spring 30, is wound in opposite hand therefrom, and its front portion nests in a hammer spring opening in hammer 24. The rear portion of the hammer spring rests on a shoulder at the juncture of the hammer spring opening and the recoil spring opening in receiver 9.

An opening, of sufficient size to allow free through passage of recoil spring 30, extends forwardly from the hammer spring opening to the forward face of hammer 24. See FIG. 1.

An opening in breech bolt 22 allows clearance for the forward portion of recoil spring guide 32 when the breech bolt is in full recoil position (FIG. 1

A bolt handle 38 (FIGS. 2, l8, and 19) allows manual operation of the breech bolt and a longitudinally-extending bolt handle slot 40 in receiver 9 prevents breech bolt rotation during its reciprocating travel.

A retaining notch 42 allows the bolt handle to be rotated upwardly, carrying the breech bolt therewith, and the breech bolt may be thereby retained in a rearward open position, when desired (FIGS. 2, l8 and 32).

THE FIG. 1 POSITION. (CLOSED, READY-TO- FIRE) In the closed, ready-to-fire position of FIG. 1, the front portion of recoil spring 30, through recoil spring washer 36, pushes forwardly upon breech bolt 22 to maintain same in closed position, and the rear end of the recoil spring bears on the enlarged head of recoil spring guide 32 to push rearwardly on upwardly-extending rearward portion 34 of sear 10 to cause the sear to pivot on trigger-sear pin 12 and to maintain the sear point of the sear in the sear notch of hammer 24.

The pressure of the recoil spring on the sear, owing to elongated slot 14 in the sear, pushes the sear rearwardly along trigger-sear pin 12, but with the sear point of the sear in the sear notch of the hammer and with the breech bolt in forward ready-to-fire position, the recoil spring is under preload (to keep the breech bolt in closed position) and the hammer spring is under full load.

The greater force (exerted by the hammer spring in pushing forwardly on the hammer which is connected to the sear in that the sear point of the sear is maintained in the sear notch of the hammer) overcomes the weaker force (of the recoil spring pushing rearwardly on the sear through sear rearward portion 34), wherefor the sear is motivated forwardly along triggersear pin 12 until stopped when the rear wall of the elongated slot abuts the trigger-sear pin.

The finger portion of trigger 11, forwardly biased by means to be described, is in forwardmost position and a bent portion 44 of sear is under a pull surface 46 of the trigger.

THE FIG. 2 POSITION (THE TRIGGER HAVING BEEN PU LLED AND THE HAMMER HAVING BEEN RELEASED BY THE SEAR) FIG. 2 shows the firearm immediately following the release of the hammer by the sear, the trigger having been pulled. The scar point of sear 10 has been withdrawn from the sear notch of hammer 24 as pull surface 46 of trigger l1 presses downwardly on bent portion 44 of the sear. Rearward movement of the finger portion of the trigger, following the release of the hammer by the sear, is precluded by the fact that the extreme upper rear of the trigger strikes the lower rear portion of receiver 9.

Further in this view, the hammer will be observed to have moved slightly forwardly under the tension of the hammer spring. The sear, relieved of the forward ten sion exerted by the stronger fully-loaded hammer spring through the sear notch of the hammer engaging the sear point of the sear, is now under a rearward pressure of the weaker preloaded recoil spring 30 through the recoil spring guide pressing upon rearward portion 34 of the sear. So relieved of the forward tension of the hammer spring, the sear has been able to move rearwardly under the rearward tension of the recoil spring and along trigger-sear pin 12 until further movement is precluded when the forward wall of the elongated slot in the sear abuts the trigger'sear pin. Bent portion 44 of the sear has moved rearwardly therewith and out of contact with the pull surface of the trigger. Meanwhile, relieved of the downward pressure exerted by the pull surface of the trigger, the sear point of the sear has been urged upwardly until the sear point is in contact with the hammer periphery rearwardly of the sear notch.

Elongated slot 14 is rearward with respect to triggersear pin 12 and the finger portion of the trigger is in the rearmost position, held there by the finger of the operator.

THE FIG. 3 POSITION THE MOMENT OF DISCHARGE) The FIG. 3 showing exemplifies the components in their positions at the moment of discharge with hammer 24, under tension of hammer spring 28, having moved forwardly, struck a firing pin 47, and fired the cartridge. The rear end of the hammer has cleared the sear point of the sear so that the forward end of the sear has moved upwardly until such upward movement is precluded when a flat on its upper forward portion contacts the lower cylindrical surface of receiver 9. Bent portion 44 of the sear has also moved upwardly into a position slightly rearwardly of a retaining notch 48 in the trigger.

Elongated slot 14 in the sear has remained rearwardly with respect to trigger-sear pin 12. Hammer spring 28 and recoil spring 30 are now both in a preloaded condition. The finger portion of the trigger is now under no spring tension, there being no contact between the sear and trigger at their forward ends. The trigger is held rearwardly by the operators finger.

A slight camming angle may be provided on the forward face of bent portion 44 and a corresponding angle may be provided on retaining notch 48 of the trigger.

THE FIG. 4 POSITION (FULL RECOIL) FIG. 4 exemplifies the full recoil position wherein breech bolt 22 has recoiled to the rear, an extractor 50 has pulled the fired shell (not shown) from the chamber, and an ejector point 51 of a magazine catch and ejector 52 has thrown the shell outwardly from the ejector port 54 (see FIGS. 11, 14, 34, 35 and 38).

Breech bolt 22 and hammer 24 have been stopped from further rearward movement by the rear end of the hammer which strikes recoil surface 26 of receiver 9. The sear point of the sear has first moved downwardly as the rear portion on the hammer passed thereover, and has then moved upwardly into the overtravelled portion of the sear notch of the hammer, the sear point being biased upwardly by fully-loaded recoil spring 30 through recoil spring guide 32.

As trigger 11 was pulled, elongated slot 14 in the sear remained rearwardly with respect to trigger-sear pin 12. Bent portion 44 of the sear remained, unchanged from the FIG. 3 position, rearwardly of retaining notch 48 in the trigger. Hammer spring 28 and recoil spring 30 are both in fully-loaded condition.

The finger portion of the trigger is held rearwardly but remains under no spring tension. If the operators finger were removed from the trigger, the position of the trigger would remain unchanged or, if pushed forwardly, would remain in forward position, the condition prevailing because bent portion 44 of the sear is not in contact with the forward part of the trigger.

At the completion of its rearward recoil stroke, breech bolt 22 (under tension of recoil spring 30) and hammer 24 (under tension of hammer spring 28) move forwardly unisonly until the sear notch of the hammer engages the sear point of scar l0. Thereupon, the sear retains the hammer, and the breech bolt continues forwardly under the recoil spring tension, through recoil spring washer 36. Meanwhile, the sear moves forwardly with the hammer which is under the forward tension of the fully-loaded hammer spring. The hammer moves forwardly and pulls the sear forwardly therewith a distance equal to the clearance between the front of bent portion 44 of the sear and retaining notch 48 in the trigger, all accomplished by the fact that the sear point of the sear is engaged in the sear notch of the hammer and overcomes the weaker partly loaded recoil spring pushing rearwardly on the sear through the rearwardly enlarged portion of the recoil spring guide bearing on the upwardly extending portion 34 on the sear.

THE FIG. 5 POSITION (IMMEDIATELY PRIOR TO THE RELEASE OF THE TRIGGER FORWARDLY) In FIG. 5, the firearm is shown immediately prior to the release of the trigger forwardly. Trigger sear pin 12 is disposed between the rearward and forward walls of elongated slot 14 in the sear, the breech bolt having closed and being under tension of the recoil spring under preload through the recoil spring washer, the hammer having been cocked, and the finger portion of the trigger being held in rearward position by the operators finger.

During closing movement, the cartridge has been stripped from the magazine and loaded into the chamber.

The forward end of bent portion 44 of the sear is in contact with trigger retaining notch 48 at a point below the trigger pivot point on trigger-sear pin 12. Forward pressure exerted by the fully-loaded hammer spring, through the sear notch of the hammer and the sear point of the sear upon retaining notch 48 of the trigger, biases the trigger in a counterclockwise direction overcoming the weaker preloaded recoil spring, as the sear moves forwardly, so as to urge, when the operator releases the trigger, the front end of the trigger upwardly and the finger portion of the trigger forwardly.

Retaining notch 48 has moved upwardly to a point where it no longer holds the sear in rearward position, wherefor the sear moves forwardly and the bent portion thereof moves under pull surface 46 of the trigger until further forward movement is precluded when the rear wall of the elongated slot abuts trigger-sear-pin l2 and further forward movement of the finger portion of the trigger is precluded when an upper horizontal surface 56 of the trigger contacts the lower outside portion of the receiver.

The components thus again assume the Fig. l position, with elongated slot 14 being forwardly with respect to trigger-sear pin 12, bent portion 44 of the sear being under pull surface 46 of the trigger, the hammer being cocked, the breech bolt being in closed position, and the finger portion of the trigger being in forwardmost position so that, if again pulled, the firearm will discharge.

As sear slides along trigger-sear pin 12, the sear is stopped from further longitudinal movement at the extremities of its travel by the respective end walls of the elongated slot.

Magazine catch and ejector 52 is a stamping with its main body being twisted so that its lower part is normal to the plane of its upper part. The extreme lower portion consists of a magazine retaining surface 66 and a thumb piece 68. See FIGS. 34 and 35. A bend in the top of the magazine catch and ejector (FIGS. 18 and 35) offsets the upper portion thereof from the center line of the receiver so as to align adjacent the right hand side of a left hand (as viewed from the rear) magazine clearance slot 69 of breech bolt 22, wherefor ejector point 51 provides the ejector function.

The magazine catch and ejector extends through a centrally-located longitudinally-extending slot in the lower portion of the receiver and rearwardly of an opening for admitting a magazine housing 70.

A pair of guide ears may be formed forwardly from the lower portion of the magazine catch and ejector for freely embracing the lower rear outer surfaces of the magazine housing so as to prevent lateral movement of the lower portion of the magazine catch.

The magazine catch and ejector exploits an inherent spring tension to retain a magazine 72 and is assembled under preload whereby forward pressure is exerted by the lower forward portion of the catch on the lower rear portion of magazine housing 70.

Magazine retaining surface 66 overhangs the rear wall of the magazine housing and extends under the rear portion thereof.

Magazine 72 (FIGS. 36 and 37) is pushed upward into the magazine housing, with the forward surface of thumb piece 68 being cammed rearwardly (when contacted by a lug 73 on the back wall of the magazine) and remaining in a rearward position until the magazine is fully seated in the magazine housing. At this time, the magazine catch moves forwardly by means of its inherent spring tension and magazine retaining surface 66 moves underneath the lug and retains the magazine in place. Rearward pressure of the operators thumb on thumb piece 68 enables the magazine to be withdrawn from the magazine housing.

The vertically-extending lateral portion of the magazine catch, which provides spring tension thereto, may be hollow to give greater resilience.

Magazine housing 70, in the form of a rectangular downwardly-extending hollow member, is provided with retaining means secured to its upper front and rear outside surfaces. As shown in FIGS. 23 and 24, an upper rearwardly-extending arcuate lug on the magazine housing embraces the lower inside wall of the receiver and, if desired a lower rearwardly-extending arcuate lug may also be employed to embrace the lower outside wall of the receiver, as shown in FIG. 1, all to prevent vertical movement of the rear of the housing.

An integral feed ramp portion 74, for guiding the cartridges from the magazine into the chamber, extends from the upper front surface of the magazine housing. A lug portion 75, integral with and forwardly of the feed ramp portion, is receivable in a laterally-extending opening in the rear face of the barrel below the chamber, thereby preventing vertical movement of the front end thereof. Lateral movement of the magazine housing is prevented by the upper outside walls of the housing contacting the inner vertical longitudinal surfaces of the magazine opening in the lower portion of the receiver.

Rearward pressure, from the cam surfaces on the lower rear portion of a bedding plate 76 on the forwardly facing cam surfaces of the magazine housing lugs 95, firmly locks the magazine housing and ejector in place upon the tightening of a takedown screw 77.

Firing pin 47 seats in a centrally-located opening in the upper portion of the breech bolt and a rearwardlylocated downwardly-extending retaining lug is disposed in an opening of sufficient length to allow necessary longitudinal movement. Vertical movement of the firing pin is prevented by contact of its lower portion with the lower surface of a firing pin opening in the breech bolt and by contact of its upper portion with the upper inside surface of the receiver.

The front of the firing pin is offset downwardly to allow the front end of the pin to contact the cartridge primer. See FIGS. 1 and 19.

A longitudinally-extending spring (not shown) may be provided to retain the firing pin in a rearward position, when out of contact with the hammer.

Proper clearance is maintained at the lower forward end of the breech bolt to clear the top portion of the magazine and the ejector (See FIG. 19).

With reference to FIG. 14, extractor 50 is formed of .round stock and bent in the form of a U, with the front end slabbed off at an angle to form the extractor hook. The extractor is retained in place by a flat extractor spring 79 biased downwardly on the rear end of the U bend in the extractor. To remove the extractor from the breech bolt, the forwardly and outwardly extending front end of the extractor spring may be lifted outward with a thumb nail so that the spring may be pulled forwardly from its opening in the breech bolt. Thereafter, the extractor may be lifted laterally from the extractor opening in the breech bolt.

The upper portion of a takedown lug 81 (FIGS. 30 and 31) extends laterally through a dovetailed opening in the rear lower portion of the barrel and through a mating clearance opening in the forward lower portion of the receiver. A threaded vertical opening in the lower portion of the takedown lug accepts upwardlyextending takedown screw 77, which passes through an opening in the lower portion of a U-shaped cam lock 84, the bottom of which is adjacent bedding plate 76.

An alternate form of cam lock 84a made from a stamping, may be provided and same is shown in FIG.

The bedding plate (FIGS. 39 and 40) and associated components may best be observed in FIGS. and 38.

Laterally-extending cam surfaces 86 on the upper ends of cam lock 84 bear on mating cam surfaces 87 on the lower front portion of the receiver.

An escutcheon 88, bedded in the lower portion of the stock, accepts takedown screw 77 therethrough. The portion of the takedown screw within the escutcheon also serves as a recoil lug.

Bedding plate 76, a longitudinally-extending member, is U-shaped in cross section. Cam surfaces on the lower rear bifurcated portion contact complementary forwardly-facing cam surfaces on magazine lug 95 thereby urging the magazine housing downwardly and rearwardly as the bedding plate is pulled downwardly by takedown lug 81 as it contacts the lower inside portion of the bedding plate while being pulled downwardly by takedown screw 77. An elongated opening in the bedding plate, the takedown screw passing therethrough, allows longitudinal movement of the bedding plate. See FIG. 39.

A forwardly-facing stop surface on the front end of the bedding plate contacts a complementary stop surface 91 in the fore end to prevent forward movement of i the bedding plate as it cams the magazine housing rearwardly.

A lower forward flat portion 90 of the bedding plate bears on a complementary surface 92 of fore end 4 that acts as a front begging surface. Metal or plastic inserts (not shown) may be placed on bedding surface 92 and stop surface 91 of the fore end to prevent wear. See FIG. 38.

The firearm assembly and the locking action of the bedding plate is now described, bearing in mind the schmatic showing of the assembly locking means in FIG. 33. Safety 13 is placed adjacent the vertical flat on the rear of the receiver with detent portion 19 of the safety placed in the fire detent. The trigger and sear are placed in their respective slots. The elongated openings in the safety and sear and the circular opening in the trigger are then aligned with the lateral opening in the receiver for reception therethrough of the straight portion of trigger-sear pin 12.

Retaining bend 17 of the trigger-sear pin is pulled rearwardly under tension and placed in opening 18 in the safety.

Recoil spring guide 32 is placed within the coils of recoil spring 30 and the spring abutting the enlarged rear portion of the recoil spring guide is compressed upon'the shaft thereof.

The slotted portion of recoil spring washer 36, with its concave side facing rearwardly, is assembled upon the rectangular portion of the recoil spring guide. The recoil spring is released to allow the foremost coils to bed within the concave portion of the recoil spring washer and the forward circular portion of the recoil spring guide retains the recoil spring and recoil spring washer upon the shaft of the recoil spring guide.

An end of hammer spring 28 is placed in the hammer spring opening in the rear end of hammer 24. With the hammer spring to the rear, hammer and hammer spring are assembled in receiver 9 from the front end, the free end of the hammer spring being receivable within the hammer spring opening in the receiver.

The recoil spring, with the recoil spring washer forwardly, is assembled through the recoil spring opening in the front end of the hammer and is passed therethrough until rearward travel is terminated by the rear face of the recoil spring washer contacting the forward end of the hammer.

Should the recoil spring washer inadvertently become lost, the recoil spring guide and recoil spring and hammer spring may still be assembled in the receiver but buckling of the recoil spring must be avoided.

Extractor 50, with its hook portion forward, is placed laterally in the extractor opening in the breech bolt. The flat end of extractor spring 79 is pushed rearwardly into the provided longitudinally-extending opening in the breech bolt until further movement is precluded by the rear end of the extractor spring striking the end of the opening, by which time the forward end of the extractor spring will have passed rearwardly over the mid or high portion of the inverted U of the extractor thereby retaining the extractor spring in place and providing lateral or inward bias of the extractor. Firing pin 47 is then placed in the longitudinally-extending slot in the uppermost portion of the breech bolt.

The breech bolt, with the extractor forwardly, is pushed rearwardly into the front of the receiver. The enlarged portion of the recoil spring guide clearance opening in the rear end of the breech bolt aligns with the forward end of the recoil spring guide and the forward portion of the recoil spring washer nests itself therein.

Further rearward movement of the breech bolt enables the bolt handle opening in the breech bolt to be aligned with ejector port 54 whereby bolt handle 38 may be placed in the proper opening in the breech bolt. Ejector port 54 being of greater width than the diameter of the bolt retaining portion 93, the bolt handle may be assembled therethrough and into the appropriate opening in the breech bolt whereby the bolt retaining portion may be fully seated in the concentric large diameter opening in the side of the breech bolt.

With the safety in fire position, the bolt handle is pulled to the rear, carrying the breech bolt therewith, and the neck portion of the bolt handle is caused to enter bolt handle slot 40 in the receiver. Thereafter, the bolt handle is pulled further rearwardly until its neck portion is aligned with bolt handle retaining notch 42 and is then pulled upwardly to rotate the breech bolt, thereby retaining the breech bolt in a rearward position.

With the barrel in place, the bolt handle cannot move forwardly to a point where it enters the ejector port and is therefore retained in place.

The upper portion of the magazine catch and ejector, below the offset bend, is pushed rearwardly into the longitudinally-extending opening in the lower portion of the receiver, rearwardly of the opening for receiving the magazine housing. Rearward movement is precluded when the rear portion of the catch within the slot strikes the rear end of the slot.

Upward movement of the front end of the magazine catch and ejector is precluded by the lower portion of notch 94 in the upper front end of the catch bearing on the under side of the lower rearwardly-extending arcuate lug on the upper rear portion of the magazine housmg.

If the lower arcuate lug is omitted, notch 94 would be moved upwardly, replacing an opening in the magazine catch and ejector that provides a clearance for the upper arcuate lug (FIGS. 34 and 38). The lower portion of notch 94, in its new location, will then contact the underside of the upper arcuate lug to prevent unwanted upward movement of the magazine catch and ejector.

Downward movement of the catch is prevented by the lower portion of the offset bend bearing on the lower inside surface of the receiver (FIG. 18) and upward movement of the rear portion is precluded by a rearwardly-extending portion bearing on the lower outside surface of the receiver (FIG. 1

The extreme front end of the upper portion extends slightly forwardly into the magazine housing opening so as to be contacted by the rear end of magazine housing 70 at the final tightening of the takedown screw.

The upper portion of the magazine housing is pushed upwardly and forwardly into the appropriate opening in the lower portion of the receiver. The front end is dropped slightly while the magazine housing is moved rearwardly and the two rearwardly extending arcuate lugs are caused to embrace the lower portion of the receiver at the rearmost end of the housing opening therein.

The rear end of the barrel is placed in the opening in the front end of the receiver and pushed rearwardly and the laterally extending opening in the rear of the barrel just below the chamber, is caused to be aligned with lug portion 75 of feed ramp portion 74 attached to magazine housing 70. The lug portion fits snugly into the laterally-extended slot in the barrel.

Continuing the barrel movement rearwardly in the receiver causes lug portion 75 to fully enter the laterally-extending slot in the barrel and the dovetailed slot in the barrel to be aligned with an appropriate opening in the forward lower portion of the receiver.

The upper male dovetailed portion of takedown lug 81 is pushed laterally through the complementary opening in the lower front end of the receiver and into the dovetailed slot in the barrel, thereby retaining the barrel loosely in the receiver. The opening is of sufficient size to provide a slight all around clearance in the receiver for the dovetailed portion of the takedown lug.

Cam lock 84 is pushed upwardly to embrace the downwardly extending portion of the takedown lug. The upwardly extending arms of the cam lock are bent slightly inwardly to provide sufficient tension to enable the cam lock to be retained on the takedown lug during preliminary assembly.

The bedding plate, with its bifurcated portion to the rear, and with its elongated slot downwardly, is pushed rearwardly over, and embraces, the assembled takedown lug and cam lock. Continuing rearwardly, the lower rear portions of the bifurcations are caused to contact the complementary magazine housing lugs 95 which are attached to or made integral with magazine housing 70.

To assemble the mechanism to the stock, the barrel and receiver with all parts attached thereto including the rear bifurcated portion of bedding plate 76 resting on magazine housing lugs 95 are grasped with the left hand. The thumb and fingers hold the forward portion of the bedding plate rearwardly and upwardly toward the barrel.

With the stock in the right hand, the lower portions of the assembled mechanism are placed in appropriate openings in the stock. The takedown screw is pushed upwardly through the escutcheon and the elongated opening in the bedding plate and through the circular opening in the cam lock and is screwed by hand into the threaded opening in the takedown lug whereby, when the takedown screw is further tightened, locking action ensues.

The tightening of the takedown screw with a large coin or the like pulls the takedown lug downwardly as the head of the takedown screw presses upwardly on the bottom surface of the stock through the escutcheon (See FIGS. 33 and 38). The upper dovetail portion of the takedown lug bears upon the complementary dovetails in the lower rear end of the barrel and centers the takedown lug in relation to the dovetail slots as the barrel is pulled downwardly and the bottom of the barrel contacts the inside bottom of the front of the receiver.

The receiver, with the barrel attached, continues downwardly until the rear bottom portion thereof contacts rear receiver bedding surface 98 of the stock and the lower rear cam surfaces of the bedding plate 76 firmly contact cam surfaces of magazine housing lugs 95, forward portion of which now contacts front bedding surface 92 and the rear end thereof contacts the cam surfaces of magazines housing lugs 95. Thereupon, as the rear end of the receiver is pulled downwardly, upper cam surfaces 86 of cam lock 84 are forced into firm contact with complimentary receiver cam surfaces 87 centering the barrel longitudinally in the receiver in relation to cam lock 84 and to the takedown lug.

Meanwhile, additional downward pressure is applied by the rear cam surfaces of the bifurcated portion of the bedding plate on the cam surfaces of magazine housing lugs pulling the receiver firmly against rear bedding surface 98 of the stock and urging the bedding plate forwardly until the front end firmly contacts complementary vertical fore end bedding surface 91 and the lower forward end of the bedding plate bears on the front bedding surface 92 of the fore end.

Meanwhile, downward pressure on the cam surfaces of the magazine housing lugs by the lower rear cam portions of bedding plate 76, forcing it rearwardly and downwardly therewith and causing the bifurcated portion to press rearwardly and downwardly on the magazine housing forcing the rear wall thereof against the forwardly protruding front portion of magazine catch and ejector 52, rearward movement of same being terminated by the rear portion of the catch that is within the slot in the bottom of the receiver striking the rearmost wall of the slot.

As the magazine housing is forced rearwardly by magazine housing cam lugs 95, it is also forced downwardly, through aforesaid magazine housing lugs by the rear end of bedding plate 76, as described.

The arcuate lugs on the rear portion of the magazine housing embrace the lower wall of the receiver and in conjunction with lug portion 75 on the feed ramp of the magazine housing, within the laterally-extending slot on the rear face of the barrel, limits downward movement of the magazine housing. The magazine housing and the magazine catch and ejector are locked in place thereby and the lower rear end of the receiver is bedded on receiver bedding surface 98 in the stock and lower front end 90 of bedding plate 76 bedded on front bedding surface 92 of the fore end and the front end of the bedding plate bears against the vertical bedding surface 91.

In FIG. 43, an alternate form of feed ramp 74a of the magazine housing is illustrated with a lug portion 7511 that has a lower arcuate surface which bears on the lower inside surface of the receiver underneath a slabbed off portion of the rear of the barrel instead of being inserted in a lateral slot in the rear of the barrel underneath the chamber.

Final tightening of the takedown screw finalizes the locking action by pulling the receiver downwardly thereby increasing pressures previously described and further securely locking the barrel in the receiver, the magazine housing in the receiver, the magazine catch in the receiver and the barrel-receiver and related parts securely in the stock. The barrel is free floating in the fore end.

In assembly locking, the final tightening of the takedown screw centers the barrel longitudinally in respect to the takedown lug, centers the barrel and takedown lug longitudinally in respect to the receiver by means of cam surfaces 86 and 87, centers the barrel laterally in the receiver, locks the barrel in place in the receiver, locks the takedown lug in the barrel, locks the cam lock on the bedding plate, cams the magazine housing rearwardly through the magazine housing lugs, locks the magazine catch and ejector in the receiver, locks rear end of the receiver on the rear bedding surface of the stock, locks the front end of the bedding plate on the front bedding surface of the fore end, locks the front end of the bedding plate against the stop surfaces of the fore end, locks the rear end of the bedding plate down upon the ears of the magazine housing, locks the upper portion of the magazine housing in the receiver, and locks the head of the takedown screw (through the escutcheon) to the bottom of the stock hence locking the entire firearm mechanism securely in the stock.

From the foregoing description, it will be appreciated that what we have disclosed is an autoloading firearm of the blowback type which is operable with but a pair of helical springs so arranged that a pressure differential between a fully-loaded hammer spring and a preloaded recoil spring, with the hammer cocked and with the breech bolt driving forwardly to closed position, is such as to cause a sear to move forwardly along a pin which also provides spring tension for the safety serving as both a trigger pivot pin and a sear pivot pin through the means of an elongated slot in the scar, and also so as to cause the sear to move and a bent portion thereof also moves forwardly therewith beneath a pull surface of the trigger whereby the finger portion of the trigger is biased forwardly. The hammer spring serves the function of the usual trigger spring, and the recoil spring exerts a continuous rearward pressure upon an upwardlyextending portion of the sear, above the pivotal elongated slot, so as to bias upwardly a forward portion of the sear wherefor an uppermost sear point of the sear engages in a peripherally-located sear notch of the hammer at the appropriate time whereby the recoil spring serves the function of the usual sear spring.

The scar, with its upwardly-extending rearward portion and elongated slot therebelow cooperating with a bent portion which contacts a pull surface of the trigger functions as a disconnector, due to a longitudinal movement allowed by the elongated slot.

Rearward pressure from a recoil spring guide, forced rearwardly by the recoil spring which biases the forward portion of the sear upwardly, allows the sear point of the sear to contact the sear notch of the hammer, thereby eliminating the dictate :for a separate sear spring.

Forward pressure through the sear point due to a fully-loaded hammer spring causes the bent portion of the sear to contact the retaining surface of the trigger with the trigger held rearwardly and to bias the finger portion of the trigger forwardly when the trigger is released thereby eliminating the dictate for a trigger spring.

The trigger-sear pin provides the pivoting means for both the trigger and the sear, with one extremity of the pin being coiled so as to provide a detent notch tension.

In order to prevent undue stress upon the trigger-sear pin by the kinetic energy imparted thereto by the stoppage of the sear, the elongated slot may be lengthened and the sear may be configured so as to be caused to strike the rear of the recoil spring bore in the receiver prior to the contacting of the front wall of the slot.

Additionally, forward movement of the sear may be arrested by a forwardmost portion of the sear being caused to abut the forward wall of the sear opening in the lower rear portion of the receiver.

With the engagement of a single takedown screw by a coin or similar object, the entire weapon including the barrel and receiver may be completely assembled or disassembled, without the use of additional tools. 7

The breech bolt and hammer and associated parts are assembled or disassembled from the forward end of the receiver, permitting a streamlining of the receiver rearward end to make it integral with the cylindrical forward end and avoiding the usual unsightly receiver midsection.

The trigger sear and safety are operative upon a common pivot pin which, significantly, is the only pin in the firearm.

The trigger-sear mechanism is capable of semi-automatic fire without a trigger spring or sear spring.

The magazine catch and ejector are combined into a unitary component, utilizing its own inherent spring tension for magazine retention and held fast in the lower portion of the receiver by means of the magazine housing and without the usual pins or screws.

The magazine housing in situ by its own upper forward end portion and defines a feed ramp entering a lateral slot in the rearward barrel face, while the rearward end of the magazine housing is retained by a pair of arcuate rearwardly-extending projections and engageable with the lower portion of the receiver at the rear of the magazine housing opening.

The takedown screw, the only screw in the operating mechanism, may be tightened so as to force the rearward end of the bedding plate downwardly and the magazine housing rearwardly and downwardly to lock the magazine housing and the magazine catch-ejector in place and render them immovable. Simultaneously a takedown lug, drawn downwardly by the takedown screw, solidly locks and centers the barrel with respect to the receiver and the entire mechanism is locked in place with respect to the stock.

Whereas normally, in firearms of this type, only the trigger is blocked when the safety is placed in safe position, herein the safety blocks the trigger against pulling rearwardly therewith and additionally precludes unwanted vertical reciprocation of the sear.

If desired, receiver 9 could be provided with a vertical undercut, not shown, adjacent the forward end of its vertically-disposed longitudinally-extending flat portion and extending forwardly for freely accommodating the forward end of safety 13 and the safety could be provided with a forwardly-extended portion for reception in the receiver undercut to maintain the front of the safety in contacting relationship with the receiver flat portion. I claim: 1. In a semi-automatic firearm, the combination of: a stock having a rear bedding surface, a fore end having front bedding and stop surfaces, a receiver having a rear end and a cam surface, a barrel, a breech bolt and firingpin reciprocable in the receiver, a takedown screw, a takedown lug, a cam lock having cam surfaces, a bedding plate having front and rear ends, a magazine housing having lugs, and a magazine catch and ejector, the takedown screw being tightenable for locking the barreland the magazine catch and ejector and the magazine housing in the receiver and locking the bedding plate in the fore end and in the lugs of the magazine housing and locking the cam lock to the takedown lug and locking the complete assembly to the stock. 2. In the firearm of claim 1, including a takedown screw being tightenable for locking together all of the firearm components upon final assembly.

3. In the firearm of claim 1 including a bedding plate,

a cam lock, a takedown lug, and a takedown screw extendable through the bedding plate and cam lock and bearing against the stock with the takedown lug bearing upon the barrel for the centering of the barrel relative to the stock and receiver.

4. In the firearm of claim 1, including a bedding plate having a bifurcated portion to the rear, an elongated slot downwardly and being movable rearwardly over, and embracing the assembled takedown lug and cam lock.

Claims

1. In a semi-automatic firearm, the combination of: a stock having a rear bedding surface, a fore end having front bedding and stop surfaces, a receiver having a rear end and a cam surface, a barrel, a breech bolt and firingpin reciprocable in the receiver, a takedown screw, a takedown lug, a cam lock having cam surfaces, a bedding plate having front and rear ends, a magazine housing having lugs, and a magazine catch and ejector, the takedown screw being tightenable for locking the barrel and the magazine catch and ejector and the magazine housing in the receiver and locking the bedding plate in the fore end and in the lugs of the magazine housing and locking the cam lock to the takedown lug and locking the complete assembly to the stock.

2. In the firearm of claim 1, including a takedown screw being tightenable for locking together all of the firearm components upon final assembly.

3. In the firearm of claim 1 including a bedding plate, a cam lock, a takedown lug, and a takedown screw extendable through the bedding plate and cam lock and bearing against the stock with the takedown lug bearing upon the barrel for the centering of the barrel relative to the stock and receiver.