US2099035A - Upturn-and-pullback bolt-action firearm - Google Patents

Description

A. A. ROWLEY UPTURN-AND-PULLBACK BOLT ACTION FIREARM 2 Sheets-Sheet l Filed March 21, 1934 uWfTiTTiuum Fl i Nov. 16, 1937. A. A. RowLEY UPTURN-AND-PULLBACK BOLT ACTION FIREARM Fi 1ed March 21, 1954 2 Sheets-Sheet 2 Patented Nov. 16, 1937 UNETED STA Qt'lCiF.

UPTURN-AND-PULLBACK BOLT-ACTION FIREARM Application March 21, 1934, Serial No. 716,588

3 Claims.

This invention relates to an improvement in bolt-action firearms, and particularly to boltaction firearms of the upturn-and-pullback type wherein the firing-plunger is projectable through the rear end of the breech-bolt.

In the event of the rupture of primers of cartridges being fired in firearms of the type referred to, the resultant blast would drive the firing-pin or -plunger rearwardly with such violence as to, in some instances, actually eject the same from the firearm and thus endanger the marksman and possibly others. The rupturing of cartridgeprimers, while infrequent, is a potential source of danger, and may result from many different causes, such, for instance, as a faulty primer, a burred firing-pin point, etc.

The main object of the present invention is to provide a firearm of the upturn-and-pullback bolt-action type having simple, reliable and effective means to guard against the possible tearing loose of the firing-plunger or other firing member, in the event of a ruptured primer.

Other objects and advantages will appear to those skilled in the art from the following, considered in conjunction with the accompanying drawings and the appended claims.

In the accompanying drawings:

Fig. l is a broken view in side elevation of one form of upturn-and-pullback bolt-action firearm embodying the present invention;

Fig. 2 is a view mainly in vertical central section through the receiver, bolt and a portion of the barrel, and showing the firing-plunger in the position which it assumes at the instant of the firing of a cartridge;

Fig. 3 is a similar View, but showing the firingplunger forced rearwardly to a degree sufficient to tightly compress the firing-spring as the result of a blow-back incident to a ruptured cartridgeprimer;

Fig. 4 is a transverse sectional view taken on the line %l of Fig. 2;

Fig. 5 is a similar view taken on the line 5--5 of Fig. 2;

Fig. 6 is a broken perspective view of the firing-plunger, detached; and

Fig. '7 is a perspective view of the springabutment sleeve, detached.

The particular upturn-and-pullback bolt-action firearm herein chosen as illustrative of the present invention includes a skeletonizecl receiver H] having a longitudinal passage I l and a loadingand-ejection opening l2. Reciprocating in the longitudinal passage ll of the receiver H3 is an oscillating:and-reciprocating bolt 13 having the usual complementary pair of locking-lugs I4l4 at its forward end designed to have their respective rear faces respectively engaged with forwardly-facing locking-shoulders !5l5 formed at the junction of the longitudinal passage ll before 5 referred to, and an enlarged bore H5 at the forward end of the said receiver.

Forwardly of the locking-shoulders |5-|5, the said bore iii in the receiver I9 is provided with internal threads [1 interengaging with similar threads l8 formed upon the periphery of the shank 59 of the firearm-barrel 20. The rear end of the said barrel 2!) is formed with the usual cartridge-chamber 2| for the reception of cartridges such as 22, having the usual primer (not shown) adapted to be struck by the firing-point 23 of a firing-plunger 24, which latter is mounted for reciprocation in a longitudinal passage 25 in the bolt I3 before referred to.

Adjacent its rear end the bolt I3 is provided with a rigid offsetting bolt-handle 26 by means of which the said bolt may be oscillated and reciprocated in the usual manner of upturnand-pullback bolt-action firearms. Immediately rearwardly of the bolt-handle 26 the bolt 13 is provided with a detachable bolt-head 27 having a forwardly-extending externally-threaded sleevelike extension 28 fitting within the internallythreaded rear end of the longitudinal passage 25 in the said bolt. The said bolt-head 21 under ordinary conditions thus forms a part of the bolt l3 and for the purpose of description may be regarded as a unit therewith.

The firing-plunger 24 before referred to is provided at its rear end with a head 29 and bears in the sleeve-like extension 28 of the bolt-head 2?, so as to be guided thereby. Encircling the firing-plunger 2 3 is a helical firing-spring 30 bearing at its rear end against a spring-abutment 3! formed by the forward end of the sleevelike extension 28 of the bolt-head 21, and bearing at its forward end against the rear end of a spring-abutment sleeve 32 fitted over the firingplunger E i and in turn bearing at its forward end against integral abutment-lugs 33--33 offsetting at diametrically-opposite points from the said firing-plunger 24 adjacent the forward end thereof. i

For the purpose of enabling the spring-abutment sleeve 32 to be maneuvered over the forward end of the firing-plunger 24 and properly seated against the forward faces of the lugs 3333, the said sleeve is formed in its forward wall 34 with a polygonal passage 35 of such size and shape as to readily pass rearwardly over the 55 firing-plunger and lying intermediate the abutment-lugs 3333 and the annular groove 36, whereby the sleeve 32 will be held against both rotary and forward axial movement with respect to the firing-plunger 24. H V

The head 29, already referred to, of the firingplunger 24 is formed on its underside with a forwardly-facing cocking-abutment 38 adapted to be engaged with the rear face of a sear-nose 39 upstanding from a pivotal sear 40, which requires no detailed description herein other than to say that it is rocked for disengaging the said sear-nose 39 from the cocking-abutment 38 by means of a pivotal trigger 4|.

Just forwardly of the head 29 of the firingplunger 24, the periphery of the latter is formed with a relatively-long-and-shallow notch 42 having a forwardly-and-outwardly-sloping transversely-extending forward wall which constitutes a safety-abutment 43 engageable, under certain conditions as will hereinafter appear, with a safety-abutment in the form of an abutment-pin 44. The said pin 44 is mounted tangentially in the bolt-head 21 so as to pass through the notch 42 for being engaged by the sloping One, end of the abutment-pin 44 isprovided with an ex' safety-abutment 43 just referred to.

ternally-threaded and kerfed head 45 fitting within an internally-threaded counterbore 46 forming the outer end of a tangential passage 41 into which the said pin 44 fits.

For the purposeof description, let it be pre- 7 sumed that the firing-plunger has just been re- I leased by the trigger 4| to the action of the firing-spring 30, which latter will thereupon drive the firing-plunger forwardly to cause the firingpoint 23 thereof to indent the primer (not shown) of a cartridge 22 in the cartridge-chamber 2I of the barrel 20, as indicated in Fig. 2 of the draw-'- ings. If, now, for any reason, the impingement of the firing-point 23 upon the cartridge-primer should occasion the rupture of the latter, a blowback of the powder-charge will occur and cause the firing-plunger 24 to'be sharply driven rearwardly against the counterurge of the firingspring 30, usually with sufficient force to tightly compress the convolutions of the said firingspring 30, as indicated in Fig. 3.

As thus positioned by the blow-back as just described, the now completely-compressed firingspring 30 will form a solid abutment and throw the full strain of checking the further rearward movement of the firing-plunger upon the portion of the front wall 34 of the spring-abutment sleeve :35: vglaiich is engaged with the abutment-lugs Under some conditions, the blow-back of burning gases as above described may be of suficient force to occasion a breakage of the slender forward portion of the firing-plunger 24 or possibly a shearing-away of the portions of the forward wall 34 of the spring-abutment sleeve 32 which are engaged with the abutment-lugs 3333. In such event the firing-plunger, or at least the rear portion thereof, would be free for being forcibly ejected from the rear end of the bolt I 3, were it not for the safety-abutment 43 and the abutment-pin 44, which are preferably so positioned with respect to each other as to interengage only after the firing-pin has been moved rearwardly sufhciently to completely compress the firingspring 30, as indicated in Fig. 3.

If the breakage of the parts as above described should occur, the rearward travel of the firingplunger will be definitely checked by the engagement of the safety-abutment 43 with the abutment-pin 44, and owing to the slopingicharacter of the said safety-abutment 43, a jamming or wedging action will be exerted upon the abutmentpin 44 of such character as to effectively check the rearward motion of the firing-plunger.

From the foregoing it will be seen that the firing-spring 33 and the spring-abutments 3| and the rear end of the sleeve 32 constitute what may beappropriately termed a primary stop for checking the rearward travel of the firingplunger. The features just referred to will ordinarily serve to completely check the rearward travel of the firing-plunger without any breakage of parts, so that the safety-abutment 43 and the abutment-pin 44 would not be interengaged and consequently distorted under ordinary conditions.

In the'event of an extremely severe rearward blow-back from a ruptured primer, or in the event of repeated blow-backs therefrom, the slender portions of the firing-plunger or the forward wall of the spring-abutment sleeve 32 may give way, in which case the safety-abutment 43 and the abutment-pin 44 will effectively prevent the ejection of the firing-plunger from the arm and consequent injury to the marksman or others.

:iIt may also here be noted that the firing-spring 30 'does not become fully compressed so as to participate, with its associated parts, in acting as a primary stop for the firing-plunger 24, until the latter has been moved rearwardly more than thedistance required to interengage its cocking-abutment 38 with the rear face of the searnose 39.

By means of the embodiment of the present invention herein shown and described, the safetyiabutments 43 and 44 are in effect stand-bys under ordinary conditions, and are not, therefore, subjected during the normal operation of the firearm to such strains as might distort or weaken them and thus measurably reduce their capacity for effectively acting in an emergency, such, for instance, as when either an unusuallysevere blow-back or oft-repeated blow-backs from ruptured cartridges take place.

The invention may becarried out in other specific ways than that herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiment is therefore tobe considered in all respects as illustrative and not restrictive, and all changescoming within the meaning and equiv,- alency range of the appended claims are intended to be embraced therein.

I claim:

1. In an upturn-and-pullback bolt-action firearm, the combination with the bolt thereof; of a firing-plunger reciprocatable in said bolt and projectable from the rear end thereof; and two complementary interengaging safety-abutments, one of which is in the form of a transverse pin carried by and supported at each of its respective opposite ends in the said bolt and the other of which is of sloping form and carried by the said firing-plunger and positioned so as to interengage when and only when the said firingplunger is moved rearwardly beyond its cocked position, to thereby guard against the rearward ejection of the said firing-plunger from the said bolt under the urge of a ruptured cartridgeprimer.

2. In a bolt-action firearm, the combination with the reciprocatable bolt thereof, the said bolt having a longitudinal firing-plunger-receiving passage therein and also having a transverse passage only partly intersecting the said firingplunger-receiving passage; a firing-plunger movable in the firing-plunger-receiving passage of the said bolt and projectable from the rear end thereof, the said firing-plunger also having a notch, the forward wall of which extends transversely thereacross; and a transverse safety stoppin installed in the transverse passage of the said bolt and laterally projecting partially into the firing-plunger-receiving passage therein into position to be engaged by the forward wall of the notch in the said firing-plunger.

3. In a bolt-action firearm, the combination with the reciprocatable bolt thereof, the said bolt having a longitudinal firing-plunger-receiving passage therein and also having a transverse passage only partly intersecting the said firingplunger-receiving passage and extending into the material of the said bolt on both sides of the said firing-plunger-receiving passage; a firing-plunger movable in the firing-plunger-receiving passage of the said bolt and projectable from the rear end thereof, the said firing-plunger also having a notch, the forward Wall of which extends transversely thereacross; and a transverse safety stoppin installed in the transverse passage of the said bolt and laterally projecting partially into the firing-plunger-receiving passage therein into position to be engaged, intermediate its respective opposite ends, by the forward wall of the notch in the said firing-plunger, the said safety stoppin being supported at each of its respective opposite ends in the said transverse passage in the said bolt.

ARTHUR A. ROWLEY.

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