US2331405A - Firearm - Google Patents

Description

Filed Feb. 27, 1941 2 Sheets-Sheet 1 Crew INVENTOR 0rd C. Loomm AGENT 0a. 12, 1943. Q LO'OMIS 2,331,405

FIREARM Filed Feb. 27, 1941 2 Sheets-She et 2 INVENTOR I Urdu ford (-Loomz-s AGENT Patented Oct. 12, 1943 FIREARM Crawford 0. Loomis, Ilion, N. Y assignor to Remington Arms Company, Inc :a corporation of Delaware Application February 2'7, 1941; Serial No. 380,

16 Claims.

This invention relates in general to firearms and more particularly to fire control mechanism therefor.

As disclosed in the prior art, the fire control mechanism of firearms and more especially firearms of the bolt action type embody, in most instances, an impact device or striker springurged to a position where it or a member mu.- ated by it, such as a firing pin, strikes the primer of a cartridge. The impact device is usually held against the action of the firing spring by a holding device or sear which is, in turn, urged into striker holding position by some suitable restraining means and released from such position by the trigger. .In addition to these fundamental elements, restraining means such as springs and adjustable screws maybe associated with the sear and trigger assembly for' varying the weight of the trigger pull, for effecting a positive but adjustable. stop tor the trigger and for limiting the movement of the trigger before and ait'er release of the sear, etc,. Heretofore these restraining elements have'been mounted usually in holes or securing means drilled or otherwise formed in or on the firearm receiverfor stock-. the dispersion of the. holes or securing means be:

ing determined more or less by the proximity of adjacent. portiphsrof' the respectivefire control elements, Thispractic'e hasproyen. dis'advantg.-. geous in that the restraining'and adjusting ele-' ments have often been located in inconvenient or substantially inaccessible places in the assembled sun so. that'the -r'ifleinan eXDriencesifcon-.

siderable difiicu'lty in "making necessary adjustments, Furthermcrerthe requirement of. a. 111.

r-ality .of dljill edgholestosflit. the severallrestrainlng means or adjustingscr'ews tends to Weaken the gun receiver or stoclcand also adds to the cost of construction and assembly. The present invention has been conceived to overcome these characteristics of the. (prior. art

, by combining all of the-restraining anti/6r adarranged so that fit-combines. inutlle structure; a plurality-of were log elements ior maintaining the-proper operation of the fire control-mechanism.

A further object is to combine sear mg means and trigger restraining means in a single device constructed and arranged so that it may -.be removably secured to a firearm by a single fastening means comprising a positive trigger stop.

Another object of this invention is to provide in a firearm a scar holding device arranged so that it combines both an adjustable trigger restraining element for taki-ngup excessive movemen-t vof the. trigger immediately following letoff" and an element for adjusting the Weight of the trigger pull.

- Qther objects, features and advantages (of the invention will become apparent from the following description tal ienlin connection with the ac companvine d a in in which I shows a side elevation mostly in section, of-a portion of-a firearm-having a. trigger cushion sprin assembly mounted thereon.

2 is a plan .view of the underside of the s ring cushion trigger assembly.

'3 shows a side elevation .of the spring u hi n assembly of Fig. 1 when the striker ha been released. Dotted lines indicate relative positions of trigger m chanism when bolt i bein Wi hdrawn- .4- is. a. side elevation of a modified spring cusbionasscmblyin com ination witba. modified fifil Rterr neio Figthe invention in its Pre en m odiment i Shown for the purpose of illustrationannlied-to a rifle of theholt action type, e ibodvins a. b l .0 moun e for d ng mov men mim rifle frame QI Z IBCGiVEIQ indic t -d er lyhy-nuirieral ll. and having the usual striker orifiring pin .l 2 the ,bolt ll) being capable of manual retraction, against normal urging 'of its spring jsand maintained in retracted position by restraini means such as a r L i t dat. libetween the side Walls of the receiver frame L The seal" 14,, as embodied in. .this invenon. Diale ts e rwe dl and w y rom, t some 1. bein vot ot e g r-1'6 y a matin Pivot 11mm co rising a s adept ed tdengage a.-s e.ar notch l9 formed in the undersidebrthe'strike L. Intbe particular sear no e s vn in ie- 1 the angle o h ta i surface 20 of the. nose is substantially at.

fight ansiest a radios times the nivot fis that; the surface {in has substantiallytengent to mam tom sis e I 's t t nde t d howeverfthat'thenn le of the surface gt relative.

to the adius through the pivot [.5 ma b? Varied climatic-negative, whereby the surface 20 and he sumac fln th t iker notc l9 contact each other at substantially the angle of repose. The trigger I6 is constructed to be supported between the side walls of the receiver on a pivot pin 22 and is urged forwardly by a trigger spring 23 preferably housed in a well 24 in the trigger, which well also receives part of a spring pilot 25 projecting upwardly from the upper surface 26 of the trigger. The trigger spring 23 exerts a constant force tending to swing the floating pivot I! of the trigger 16 in a clockwise (Fig. 1) direction about the pivot 22- so as to urge the sear M in a counterclockwise direction about its pivot I and hence hold the sear surface in engagement with the adjacent surface 2| of the sear notch 13 to prevent the release of the striker which is under the constant urge of the striker spring I3. The aforesaid pilot 25, urged by the trigger spring 23, controls the usual safety member 21 mounted on a stud 28. The parts above described constitute the usual features of bolt action firearms and in themselves are not herein claimed as novel.

In the drawings the novel trigger cushion spring assembly of this invention is'indicated, in general, by the numeral 30 and comprises a blanked and formed member made of spring steel or equivalent material having a central hub or shoulder portion 3| and two substantially diametrically opposed resilient arm portions 32 and 33 respectively. The hub 3|, as shown in Fig. 2, is of relatively large overall area as compared to the width of the resilient arms 32 or 33, and is punched or drilled out to have a smooth walled hole-34. A headed screw 35, vkerfed 'to'take a screwdriver, is adapted to pass through the drilled hole of the hub and to be threadedly engaged in a tapped hole in the bottom wall of the receiver so as to secure the spring assembly thereto and form in efiect a fulcrum for each resilient arm 32 and 33. The screw 35 is further designed to pass clear through the wall 35 of the receiver. and is provided on its projecting end with a substantially flat bearing surface 36 for thejpurpose hereinafter described. The arms 32 and 33 are of different dimensions, as shown,

the arm 32 being somewhat narrower and longer than the arm 33 so that its inherent stiifness is substantially less than that of the relatively short broad springarm 33. The terminalportion. or end of each arm 32 and 33 isbentor otherwiseformedinto a.U' as indicated 11513! and: 38 respectively, the reverse bend at the end of the arm 33 being in a downward direction: as shown. while the reverse bend on the end of the arm 32 is upward. These U-shapedends 31 and 38 of the aforesaid arms are adaptedto be drilled and tapped as at 33, 40 and 4l, 42 respectively of the drawingsand'suitable adjustablescrew bolts 43,,and 44 assembled therein. By slightly compressing each U-shaped end or loop when assembling its respective screw therein, a constant tension is maintained on the screw to prevent it from loosening. Each screw 43 and 4 4 compriss, in combination with its respective spring arm 32 and .33, adjustable restraining means forv effecting! a. restraining force against the movement of co-operating elements of the mee ing col mechanism. More particularly the screw 43 'isfconstructed and. arranged sc the-t the end 45..thereof bears directlyand continuously-against the underside of the sear and rearward of'i ts pivot J5, whereby the latter is restrained against clockwise movement about said: pivot. In this respect the screw 43 and its resilient arm 32 comprise, in efl'e'ct, a sear restraining means, the tension of which may be readily varied by turning the screw bolt 43 so as to flex the spring arm 32 from its fulcrum point 35. It will be seen that inasmuch as the weight of the trigger pull is, in accordance with the sear-trigger connection ll, directly proportional to the resiliency of the sear restraining means, the same screw and spring arm 43-42; also comprise the restraining means for adjusting the weight of the trigger pu1lthis adjustment being similarly obtained by turning the screw bolt 43. In accordance with the device of Fig. 1 a variation in trigger pull of from approximately three to seven pounds is possible, but it will be appreciated that slight changes in shape and dimensions of the device may be made within the scope of this invention whereby other minimum and maximum limits may be obtained. The adjustable screw bolt 44 is adapted, as shown, to underlie the underside of the trigger I6 and may be readily arranged to contact continuously therewith. If this is done the screw 44 and its co-operating spring arm 33 comprise restraining means which assist the force of'the trigger spring 23 in holding the sear nose I8 in the sear notch IQ of the firing pin l2. A further function of the restraining means 4433 is carried out (see Fig. 3) when the screw bolt 44 is backed off from the trigger just sufficiently to be engaged by the trigger immediately after let-on," i. e. the instant when the sear nose has just disengaged the striker notch 19, whereby substantially all further movement or overtravel (if the trigger is prevented. To this latter end'the spring arm 33 is relatively short, being ful'cr umed at bolt 35 so as tohave a stiff restraining 'fp'rce such that the trigger is arrested by tis, for this purpose, a solid or positive stop. ver, as hereinafter described, in order to with raw the bolt H] the trigger l6 may be,

pull'dback further against the restraining force of the spring 33 so asto lower the bolt-stop 46 he path of the usual bolt-lug. A final top to limit themaximum movement of ggehse ar assembly (indicated by dotted 36 of the 's'crew'3 5 which is constructed I e angedto; be engaged by the underside of the t ggeresear assembly when the latter is drawn down far enough to permit removal of thebolfithe foregoing description it will be noted th the eleunentsof the fire control mechanism in-the positions'shown in Fig. 1 the arm is'in' condition for firing. The force of the trigg'fer spring, 23, augmented by the force exerted on. the sear M by adjusting the screw 43 so as to flex the spring arm 32, restrain. the nose {8 of the sear l4 in the sear notch IQ of the striker I22 It will be, manifest that the adjustable screw 43 and, the spring arm 32, when flexed by the screw, comprise, in effect, a sear restraining means Furthermore, inasmuch as. the force of thetrigger spring is constant the force neces-- sary for the pivotal increment of thetrigger or the ,weight of the trigger pull will be directly proportional to the sear restraining force and henceit will be clear that by turning the adjustingflscrew fl an'd flexing its spring arm 32 the weight of the trigger pull may be readily controlled. Ast he shooter pulls back on the trigger he overcomes the weight of the trigger pull (or the restrainingforce of the sear restraining means) and also the force of the trigger spring so that the sear nose-l3 is withdrawn from the Fig, 3) is obtained by the aforementioned.

sear notch i9 and the striker I2 is released and springs forward due to the urge of the striker spring l3. whereupon the arm is discharged. Si-

muitanecu-sly with the release of the striker I! the trigger brings up against the adjustable trigger restraining stop 44 (as shown in Fig. 3) whereby any trig er overtra-vel after 1et-off" is prevented. The parts are now in the position shown by the full lines in Fig. 3 the striker h aving engaged the primer portion of the cartridge and exploded the charge. In this'position of the fire control mechanism it will be noted that the scar spring 32 isfiexed below its normal position (see Fig. 1) which puts a tension upon the pivoted sear, tending to return it to its original or cooked position. However no noticeable deflection of the spring 33 occurs at this time since the stiffness of the latter is such that it acts, in effect, as an immovable stop for the trigger. The firearm is reloaded in the well known manner by lifting the bolt. handle and subsequently re-locking it, whereby the sear nose It isre-engaged in the sear notch H) of the striker 12 by the tension of the flexed scar spring .32.

The dotted lines in Fig. 3 show the relative positions of the trigger-sear mechanism .to permit removal of the-bolt from the receiver. When the trigger is pulled back not only to let-01f position -but sufliciently far beyond so that the sear is rocked clockwise to thepositio-n shown by the dotted lines, the bolt-stop '46 is withdrawn from the path of the u s'ual'ho l tlug, thusnerrnitting removal of the bolt. It. will he noted tlaat in this position the resilienttriggenstop 33. 44 has beerr'ii'exed downwardly. as indicate by the dotted lines, the trig er pull necessary for flex mg the .sfiring to' this position being considerably greater than the normal trigger pull at let-- oil. Furthermore, "in, this position the searfirigger assembly is at the-"limit of .its downward movement and further movement is pre iented sser Qushionspring a, modified sear 5!].

5i 'lravinga' face 52, the angle of 'iyhose, plane is, relative to a rarlius Ugh i) ht 53, greater than 'iififi's' at surface andfthe sur- 11* mils oi'tneifiriri pin 12 race iii or t are substantially at as single, of terms rdrthese surfaces. motion is deemed desirable g iroi ceretween 15rd parts to be =-di sex 1'ga ed"arrd hence fo'r efli fig. "letmij or rele s -citri striker by an ,extre 'e-. 1y sent-c1 mioareid emenwrme trigger aster-emarter described, j I sear "5 is connected" to the trigger "by the usual floating sweets; said trigger hein'gj hi tdted at t-1 in the reenter ream-e andhavirig the-usualtrieger springjnct shown) Other elements or far ng metric-mm not shown a'reiieemed to'be wen untier'stoodby those skilled seams-asses noh=essential to the ca'r-" out of resent-intention, and hence are notdescribed j numer tor: represents a modified trigger-cushion spring which may be co'n'sii'l udted from stee l stock' or other suitableresilient material and is 'formed or strayed he as an orbrcken having u-sriapee ends evadesrs and an joined" by substanflchy pemiilelsine element/s ot spring arms fl and 58 Each-spring arm--61 most is provided-With eorfiiednele fl and 50' resnectively. A screw-r-boit'= t0 ls to pa-as Tded' with a sear. nose so as to secure the latter and hence the entire cushion spring to'the lower side of the receiver.

The'drilled hole 69 ofthe spring arm 68 is con structed large enough and arranged so that the kerfed head of the bolt .60 may pass therethrough and be easily accessible for assembly or adiustlng purposes. As in the construction shown inFig-s. land 3, the'bclt or screw fit projects through-the receiver wall 6! so that its projecting end 82 comprises a positive trigger stop. Each U-shaped endorloop 63, 64 isprcvided with an adglusting screw 65. 66 respectively in the manner and for the purpose already described in connection with the spring assembly of Fig. 1, the definition and function of each element of the modified cushion spring assembly being sub.- stantially identical to that of its corresponding part in that trigger spring assembly.- However the modified spring is characterized" by somewhatsimpler construction inthat the U-shaped ends-are .formed by reverse bends both made in an upward direction and so arranged that the adjustable screw 56 isadaptedto act as the fulcrum for the resilient spring arm 68 of the adjusting screw 65, whereby the stiffness of said spring arm is considerably less than the stillness which characterizes the corresponding spring arm 32 of the device of Fig- '1. This =feature. taken in combination with the modified sear nose and sear noto'jh constru ction,. wherein the adjacent surfaces. contact each other at an obtuse angle, efiectsan extrernel-y sensitive re straining means for controlling the. fire control mechanism. By arranging the adjusting screw 65 s that t end 12 Just .tnllnhes the underside of the sear 50, it noted that the force of he su lt'ri'gger sprin not how is subs a daily the only restraining ens acting to hold the sear iircoiitact the striker. In this case it nasbeen found-that atrigger pull .of as little -as one and ,dne-ha-lf to trim pounds is ef-- fective to release the striker. In accordance with this invention the "eight of the trigger pull may be uniformly increased in .increments of substantially one pound for -.tu'rn---,0- the ad- "the are controlhniechanism 1e modified tri er s i is. se th -sam asfl r reconnection wifliia d3. I.t' willbe r alizedffiowevefi. that iiia as. he 'slobe of surface szcfthe sear ,n sobtuse, the pressure e" I oI'tlie s notch upon the.sur-. sar'jno'seil reads toinove the sear wise and trigger counter lockwi e, which .ovement i -rei rairred sii snanriauy nl byjthe'fd cc of thtrigger ring. As the shooter 1 1111 1 X th'eitri' efi a.fi is s re.i s..qll iikly reached sufficient to were me the static fricticn ofthe sur a s. 5:. s4 and app ximately drain t {time 9t fi t igger sprin whereupon thestraining eats: the latter .is overcome adder hrust ofthe st i e? s p'r neov mic' fricti n. l 'rcthsr re r thafifihe .fili face ir m h s tqf ffihe e rndw md t e .armd h "s a This errc aetion; i; 'e. the-roekingawey of the sear nose rrchithe striifernotch; occurs without anynfiditioneilbufl-on the trigger and therefore} since-there messed no sudden release of the resistance to the pull of the finger upon the trigger, there 'i's ne'trigger-tfumiii' "This trigger constructed and arranged to form a positive trig ger stop engaging said resilient element intermediate the extremities thereof.

9. In a firearm, firing mechanism embodying an impact member; an actuating spring for the member; holding means for the member to resist the spring; a trigger having means engaging said holding means and shiftable to change the position of the holding means to be overcome by the spring in giving the member a firing throw; a positive trigger stop; and a leaf spring secured to said firearm by said stop, said spring having an extremity constructed and arranged to resist the displacement of said holding means by said trigger and a second extremity constructed and arranged to resist the movementof the trigger.

10. In a firearm, firing mechanism embodying an impact member; an actuating spring for the member; holding means for the member to resist the spring; a trigger having means engaging said holding means and shiftable to change the position of the holding means to be overcome by the spring in giving the member a firing throw; a positive trigger stop; a leaf spring secured to said firearm by said stop, said spring having diametrically opposed extremities; holding means engaging means adjacent one extremity to resist the displacement of said holding means by said trigger; and trigger engaging means adjacent the opposite extremity to effect an extremely stiff resilient trigger stop.

11. ha firearm, firing mechanism embodying an impact member; an actuating spring for the member; holding means for the member to resist the spring; a trigger having means engaging said holding means and shiftable to change the position of the holding means to be overcome by the spring in giving the member a firing throw; a positive trigger stop; and a leaf spring secured to said firearm by said stop, said spring having an arm provided adjacent the end thereof with adjustable means engaging said holding means to set the weight of the trigger pull and having a second arm diametrically opposed to said first arm and provided adjacent the end thereof with adjustable trigger engaging means to effect a resilient trigger stop.

12. In a firearm, firing mechanism embodying an impact member; an actuating spring for the member; a scar for the member to resist the spring; a trigger having means engaging said sear and shiftable to change the position of the sear to be overcome by the spring in giving the member a firing throw; a positive trigger stop; a sear spring secured to said firearm by said stop, said sear spring comprising diametrically opposed arms having U-shaped extremities; and an adjusting screw in each extremity, one screw being constructed and arranged to resist the displacement of the sear by the trigger and the second screw being constructed and arranged to resist further displacement of the trigger following let-off.

13. In a firearm, firing mechanism embodying an impact member; an actuating spring for the member; holding means engageable with the member constructed and arranged to resist the spring when said means and member are in static frictional engagement but adapted to be displaced from engagement with said member by said spring when said means and member are in dynamic frictional engagement; a trigger having means engaging said holding means and shiftable to transform said static frictional engagement of said holding means and member to dynamic friction; and means having an adjustable member in engagement with said holding means for resisting the displacement of said holding means by said trigger.

14. In a firearm, firing mechanism embodying an impact member; an actuating spring for the member; holding means engageable with the member constructed and arranged to resist the spring when said means and member are in static frictional engagement but adapted to be displaced from engagement with said member by said spring when said means and member are in dynamic frictional engagement; a trigger having means engaging said holding means and shiftable to transform said static frictional engagement of said holding means and member to dynamic friction; means having an adjustable member in engagement with said holding means for resisting the displacement of said holding means by said trigger; and means to mount said resisting means on said firearm comprising a positive trigger stop.

15. In a firearm, firing mechanism embodying an impact member having an oblique surface; an actuating spring for the member; holding means having an oblique surface engageable with the oblique surface of the member to resist the spring when said oblique surfaces are in static frictional engagement but displaceable by said spring when said oblique surfaces are in dynamic frictional engagement; a trigger having means engaging said holding means and shiftable to impart movement to said holding means thereby transforming said static frictional engagement of said oblique surfaces to dynamic friction; a resilient element secured to said firearm having members supported thereon constructed and arranged to resist the displacement of said holding means by said trigger and to resist the movement of the trigger respectively.

16. In a firearm, firing mechanism embodying an impact member having an oblique surface; an actuating spring for the member; holding means having an oblique surface engageable with the oblique surface of the member to resist the spring when said oblique surfaces are in static frictional engagement but displaceable by said spring when said oblique surfaces are in dynamic frictional engagement; a trigger having means engaging said holding means and shiftable to impart movement to said holding means thereby transforming said static frictional engagement of said oblique surfaces to dynamic friction; a positive trigger stop; and a leaf spring secured to said firearm by said stop, said spring having an extremity constructed and arranged to resist the displacement of said holding means by said trigger and a second extremity constructed and arranged to resist the movement of the trigger.

CRAWFORD C. LOOMIS.

Images