US 3253362 A
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May 31, 1966 w. c. GlTCHELL BOLT ACTIONS FOR RIFLES 3 Sheets-Sheet 1 Filed April 21, 1964 mm ww INVENTOR. W/L BUR 0. 6/ TOHEL L AT TOHNEY 3 S heet s-Sheet 2 W. C. GITCHELL BOLT ACTIONS FOR RIFLES May 31, 1966 Filed April 21, 1964 May 31, 1966 w. c. GITCHELL BOLT ACTIONS FOR RIFLES 3 Sheets-Sheet 5 Filed April 21, 1964 INVENTOR. W/LBUR C. GITCHELL ATTORNEY United States Patent 3,253,362 BOLT ACTIONS FOR RIFLES Wilbur C. Gitchell, P.O. Box 283,
Point Reyes Station, Calif. Filed Apr. 21, 1964, Ser. No. 361,429 13 Claims. (Cl. 42-16) This invention relates to a bolt action for rifles.
In bolt actions previously used in rifles the primer, which is the weakest part of a cartridge, is not supported. In previous actions, whether bolt or otherwise, when the primer is struck by a straight firing pin, the cartridge goes oif and builds gas pressure. When the pressure is sufliciently great, it flattens out the primer on the bolt face and depresses the firing pin pushing it back through the firing pin hole. This cuts a small hole in the primer letting gas escape rearward, which can damage the action as well as cause injury to the shooter.
Furthermore, previous actions do not support the cartridge case head completely. Some bolt actions are counterbored in the bolt face and these are the strongest actions to date. However, even these do not fill the extractor groove and when the pressure becomes great enough, the brass in the case head will flow into any open space not backed by steel or otherwise, thereby it deforms the cartridge case and prevents reuse of the same and also it damages the extractor.
The primary features of this invention are the provision of a bolt action, which completely seals the firing pin hole and supports the primer so as to prevent primer blow out thereby increasing the strength of the bolt action and rendering it absolutely gasproof; and also to grip the cartridge case head so as to completely fill the extractor groove with steel so there can be no movement or flow of brass in the case head.
Other features of the invention are to provide suitable means for controlling the extractors movable relatively to the bolt into and out of the extractor groove of the cartridge head according to the movement of the bolt action into and out of the receiver of the rifle.
I am aware that some changes may be made in the general arrangements and combinations of the several devices and parts, as well as in the details of the construction thereof without departing from the scope of the present invention as set forth in the following specification, and as defined in the following claims; hence I do not limit my invention to the exact arrangements and combinations of the said device and parts as described in the said specification, nor do I confine myself in the exact details of the construction of the said parts as illustrated in the accompanying drawings.
With the foregoing and other objects in view, which will be made manifest in the following detailed description, reference is had to the accompanying drawings for the illustrative embodiment of the invention, wherein:
'FIG. 1 is a perspective exterior view of the bolt action removed from the receiver.
FIG. 2 is side elevation of the receiver showing the trigger longitudinal.
FIG. 3 is a sectional view, broken away in part, the section being taken on lines 33 of FIG. 2, showing the action in the receiver in cocked attitude.
FIG. 4 is a partially fragmental longitudinal sectional view of the bolt action in the receiver in withdrawn position ejecting the empty case.
Patented May 31, 1966 FIG. 5 is cross-sectional view, the section being taken on lines 55 of FIG. 3.
FIG. 6 is cross-sectional view, the section being taken on line 66 of FIG. 4.
FIG. 7 is a cross-sectional view, the section being taken on lines 77 of FIG. 3.
FIG. 8 is a cross-sectional view, the section being taken on lines 8-3 of FIG. 3.
FIG. 9 is a perspective detail view of the movable extractor.
FIG. 10 is a partly section, fragmental subassembly view showing the relative position of the trigger to the cocking parts of the bolt action.
FIG. ll'is a partly fragmental end view of FIG. 3.
In the general organization, my bolt action 1 is movable into and out of a receiver 2 suitably secured, usually threaded, on the end of the barrel breech 3 of a rifle. The barrel breech 3 has the usual firing chamber 4 into which fits a cartridge case 6. Usually the cartridge case 6 has a case head 7 with an extractor groove 8 near the base of the case head. In the middle of the case head 7 is a primer or primer cup 9 of the usual type.
A bolt body 11 slidably fits into the recess 12 of the receiver 2. In the illustrative embodiment herein the bolt body Ill has three spaced rows of locking lugs 13. In each set of lugs 13 there are three circumferentially spaced lugs 13, and the lugs 13 of the spaced series are axially aligned so as to be slidable in the corresponding longitudinal or axial grooves 14 in the receiver recess 12. The receiver recess 12 has a series of radial locking grooves 16 spaced to correspond to the positions of the locking lugs 13 in the locked position of the bolt action so that as the bolt body 11 is turned in the locking position, the locking lugs 13 enter the respective locking grooves 16 and positively lock the bolt action in firing position. For the manipulation of the bolt action, there is a usual bolt handle 17 which works in a peripheral recess 13 in the wall of the receiver 12. In the firing or forward end of the bolt body 11 is formed a frusto-conical valve seat 19. A firing valve 21 is seated on the valve seat 19 so that the forward face 22 of the valve 21 is spaced inwardly from the end face 23 of the bolt body 11. The space thus created accommodates a firing tit 24 located opposite the center of the primer cup 9 in proper firing position. A cross pin 26 extends across an elongated slot 27 in a valve stem 23 and is secured in the bolt body 11. A coil spring 29 between the rear end of the elongated slot 27 and the cross pin 26 normally pulls the valve stem 23 rearwardly so as to seat the firing valve 21 on the valve seat 119.
A firing pin 31 extends rearwardly spaced from the.
end of the valve stem 28. The bolt body 11 has an axial bore 32 extending from the rear end so that the bottom 33 of the bore is spaced from the firing face 23 of the bolt body 11. The valve stem 28 projects through the bottom 33 into the bore 32 so as to allow for the short travel or movement of the firing pin 31 necessary to fire the cartridge.
In the rear end of the bore 32 is threaded the stem 34 of a bolt collar 36, which latter surrounds the rear end of the bolt body 11. The bolt collar 36 and its stem 34 have an axial recess 37 therethrough in which is slidable the body 38 of cocking piece 39. The rear end of the firing pin 31 is suitably secured in the cockingpiece body 38, by interlocking lugs 41 and pockets a, Q 42. The cocking piece 39 is connected to the trigger mechanism 40 of the rifle as shown in FIG. 10 for suitably cocking the firing pin 31 and for firing at will. For this purpose in the cocking piece 39 is a cam groove 43, which fits over and against a cocking cam 44 on the end of a hub 50 of the bolt collar 36. In the cam groove 43 is cam pin 45 offset 60 from the cocking cam 44 so as to be engaged by the latter when the bolt body 11 is turned 60 into retracting attitude. A firing pin spring 46 around the firing pin 31 bears against the inner end of the bolt collar stem 34 and at its other end against a flange 47 on the firing pin 31 so as to normally urge the firing pin against the rear end of the valve stem 28.
When the cocking piece 39 is cocked, it compresses the firing pin spring 46 so that when the cocked cocking piece 39 is released, the firing pin spring 46 rams the firing pin 31 against the rear end of the valve stem 28 thereby to ram the firing valve 21 toward the primer cup 9 and thus drive the firing tit 24 into the primer cup 9. As the gas pushes the primer cup 9 rearwardly, or any gas that may escape, forces the firing valve 21 against the valve seat 19 and positively seals the bolt action against any escape of gas.
In the bolt bore 32 is an actuator sleeve 48 which surrounds the firing pin spring 46 and the flange 47 and is slidable relatively to the same. The sleeve 48 is shorter than the distance between the inner end of the cocking piece body 38 and the bottom 33 of the bore 32. A coil spring 49 between the inner end of the cocking piece body 38 and the sleeve 48 normally urges the sleeve 48 toward the bottom 33 of the bore 32. The forward end of the sleeve 48 is spaced from the bore bottom 33 so as to allow relative travel of the sleeve 48. The sleeve 48 is an extractor release and it has suitable slots 51 near its forward end to be engaged by lever arms 52 of extractors 53. Each extractor 53 is curved so as to conform to one-third of the outer periphery of the bolt body 11 and is located between the bolt body 11 and the receiver recess 12. The lever arm 52 extends generally at right angles from about the middle of each extractor S3,
as shown in FIG. 9, and then pivoted in slot 54 in the bolt body 11 into the adjacent slot 51 of the extractor release sleeve 47. Each extractor 53 has its outer end bent inwardly to fit against a mitered wall 56 under the inner end of the barrel breech 3 and against the firing end of the bolt body 11. The inner end of rim of each extractor is cut so as to form a claw 58 which projects and fits into one-third portion of the extractor groove 8 of the cartridge case head 7. The claw end of rim 58 of each extractor 53 also fits over the outer periphery of the base flange 59 beyond the extractor groove 8 of the cartridge case head 7 so as to firmly and tightly hold the bottom of the cartridge case against the firing end face 23 of the bolt body 11.
The bolt body 11 also has a fixed extractor claw 61 formed thereon for the remaining third of its periphery. Thus the fixed extractor claw 61 and the claws 58 of the pivoted extractors 53 completely fill the extractor groove 8 of the cartridge and positively hold the cartridge during the firing and also during the loading and during the first portion of the extracting of the cartridge.
The receiver recess 12 has an enlarged periphery 62 from about its middle to the rear end so that as the bolt action is retracted from the receiver recess 12 after the swingable extractors 53 pass into this enlarged recess periphery, the extractor release spring 49 pushes the extractor sleeve 48 forwardly and thereby swings the extractors 53 outwardly into the enlarged recess periphery 62 thereby withdrawing the claws 58 from the extractor groove 8 to facilitate the ejection of the cartridge in the usual manner. The enlarged recess periphery 62 is circumferentially about two-thirds of the entire recess periphery and conforms to the location of the swingable extractors 53 after the bolt is turned for retracting from the receiver recess 12. In order to facilitate the insertion of the swingable extractors 53 into the receiver recess 12, the inner end of the enlarged periphery 62 is formed into a tapered shoulder 63.
To facilitate the ejection of the cartridge, there is provided an ejector pin 64 in the firing end face 23 of the bolt body 11. This ejector pin 64 has an elongated slot 66 therein through which a limit pin 67 extends to limit the outward movement of the ejector pin 64 under the action of an ejector spring 68 between the inner end of the ejector pin 64 and the bottom of the pocket 69 into which the ejector pin 68 is pushed by the base of the cartridge. When the swingable extractors 53 are permitted to swing outwardly and thereby release two-thirds of the extractor groove 8, then the spring pressed ejector pin 64 operates to push the cartridge away from the inner end face 23 of the bolt body 11, as shown in FIG. 4.- F or this purpose, the ejector pin 64 is located diametrically opposite from the fixed claw 58 thereby to cause suitable tilting of the cartridge for ejection in the usual manner of rifle actions.
The cocking piece 39 is suitable engaged by a part of the usual trigger 40 for cocking the firing pin 31. In the illustrative embodiment herein the cocking piece 39 is substantially cylindrical in cross section as shown in FIGS. 10 and 11. From the bottom 71 of the cocking piece 39 extends a cocking sear 72 to be engaged by the trigger sear 73 on the trigger cam 74. The trigger cam 74 is fulcrumed on a pivot 76 transverse relatively to the bolt and is pressed by a suitable trigger spring 77 into an initial position to hold the trigger sear 73 in the path of the cocking sear 72. The trigger lever 78 is engageable by a finger in the usual manner to turn the trigger cam 74 so as to withdraw the trigger sear 73 from the cocking sear 72, thereby to release the cocking piece 39 and allow the firing pin spring 46 to ram the firing pin 31 against the valve stem 28. The cocking sear 72 rides in a cocking groove 79 in the usual upper tang 81 on the rear end of the receiver so that rotation of the cocking piece 39 is prevented.
In operation the bolt body 11 is slidable and rotatable within the receiver 2. The bolt collar 36 is held also by a set screw 82 so as to rotate with the bolt body 11 relatively to the cocking piece 39. The cartridge 6 is inserted into the receiver 2 ahead of the retracted bolt body 11 in the usual manner. Then the bolt body 11 is pushed into the receiver 2. As the pivoted extractors 53 reach the tapered shoulder 63 of the receiver periphery, they are pushed inwardly against the bolt body 11 and the claws 58 thereof enter into the extractor groove 8 of the cartridge. The remaining portion of the extractor groove 8 is engaged by the fixed claw 61. The cartridge 6 is thus pushed into the firing chamber 4 of the barrel breech 3 as shown in FIG. 3. Then the bolt body 11 is turned so as to interlock the locking lugs 13 with the locking grooves 16 of the receiver 2. As the bolt body 11 is pushed into the receiver 2 the trigger sear 73 blocks the cocking sear 72 before the bolt body 11 is completely inserted thereby to cock the firing pin 31 and compress the firing pin spring 46. When the trigger is pulled and the cocking sear 72 is released, then the firing pin spring 46 rams the firing pin 31 against the valve stem 28 and thus rams the firing tit 24 into primer cup 9. The gases generated by firing push the primer cup 9 against the firing valve 21 and seat the valve 21 on its valve seat 19, thereby sealing the passage in the bolt body 11. After the firing the bolt body 11 is turned so as to withdraw the locking lugs 13 from the locking grooves 16 and then the bolt body 11 is withdrawn from the receiver 2. As the pivoted extractors 53 pass rearwardly beyond the tapered shoulder 63, the action of the extractor spring 49 pushes the extractor actuator sleeve 43 forward so as to push the lever arms 52 forward and thereby urge the extractors 53 outward, to release the extractor groove 8 of the cartridge 6. Thereupon the ejector pin 64 tilts the cartridge about the fixed claw 61 as a fulcrum toward and out through the ejection port 83.
Then the rifle may be reloaded and fired again as heretofore described. The cocking piece 39 is cocked also when the bolt body 11 is turned about sixty degrees from the full line position shown in FIG. 8 to the dotted line position of the handle 17. The steepness and depth of the cocking cam 44 on the end of the receiver hub 50 is such that by such sixty degree turn into open or retracting position of the bolt relatively to the cocking piece39, the interaction of the cam pin 45 and the cocking cam 44 pushes the cocking piece 39 away from the bolt collar hub 50 so that the cocking sear 72 is pushed over and beyond the trigger sear 73 and is held cocked by the latter. During the full retraction of the bolt the aforesaid cam action holds the cocking piece in such spaced attitude so that when the bolt is reinserted into the receiver 2 and turned back sixty degrees to the locked firing position then the cam pin 45 and the cocking cam 44 are out of alignment and spaced from one and other as needed for the action of the firing pin, as shown in FIG. 3.
1. In a bolt action in firearms for loading and ejecting a cartridge having a casing with a flat end and having a primer in the center of said fiat end,
(a) a bolt body having a flat faced firing end and a cocking end,
(b) said flat faced firing end'having an axial recess therein conforming generally to the contour of said primer,
(c) a valve seat formed in the bottom of said recess,
(d) a firing valve in said recess seated on said valve seat by the gas generated by the firing of said primer thereby to prevent escape of gas from said primer and from said recess,
(e) a firing member on said valve to fire said primer,
(f) cockable ramming means in said bolt spaced from said valve when cocked,
(g) means on said valve slidable in said flat faced firing end for coacting with said ramming means for ramming said valve and said firing member against said primer for firing the primer,
(h) releasable means for cocking said firing pin.
2. The bolt action defined in claim 1, and
(g) said firing member on said valve being a projection extended from said valve toward said primer.
3. The bolt action defined in claim 1, and
(g) said cockable ramming means including a firing pin axially aligned with said valve and (h) resilient means to ram said firing pin against said valve.
4. In a bolt action as defined in claim 1, and
(i) said cartridge having an extractor groove adjacent said flat end,
(j) claw means engaging said extractor groove to hold said fiat end of said cartridge against said flat faced firing end.
5. The bolt action defined in claim 4, and
a (k) said claw means engaging the extractor groove of said cartridge all around.
6. The bolt action defined in claim 4, and said claw means including (k) a fixed claw extending from the firing end of said bolt and around one-third of the periphery of the end of said bolt, and
(l) a pair of movable claws, each extending around another one-third of the periphery of said bolt,
(m) and means coacting with said receiver for closing and opening said movable jaws respectively as the bolt is inserted and retracted.
7. The bolt action defined in claim 4 and (k) resilient means to urge said valve normally onto said valve seat.
8. The bolt action defined in claim 7.
(i) said valve seat having a recess in front of said valve for accommodating said firing projection.
9. In a bolt action for firearms, means for loading and 6 extracting a cartridge, said cartridge having a primer in its base and an extractor groove around its base periphery, comprising,
(a) a bolt body having a firing end and a cocking end (b) means in the firing end of said bolt for ramming said primer for firing said cartridge (c) a fixed claw extended from the firing end of said bolt around a portion of the periphery thereof for engaging a portion of the periphery of said extractor groove (d) a plurality of pivoted claws extending from said firing end of said bolt into engagement with all the remaining portions around said extractor groove thereby to clamp the entire groove periphery and prevent swelling of said casing at said groove (e) a receiver on the firearm for receiving said bolt having an ejection port on a side thereof (f) means in said receiver to press said ivoted claws into said extractor groove at about the point of loading in said receiver during the movement of said bolt inwardly of said receiver and to release said pivoted claws at said loading area of the receiver during the retracting of said bolt from said receiver (g) said fixed claw being aligned with the ejection port of said receiver during the retracting of said bolt (h) and ejector means in the firing end of said bolt abutting the base of said cartridge eccentrically and generally diametrically opposite to said fixed claw thereby to tilt and eject the cartridge through said ejection port.
10. The bolt action defined in claim 9, and
(i) resiliently yieldable means in said bolt connected to said pivoted claws normally to urge said pivoted claws into cartridge releasing position.
11. In a bolt action for firearms, means for loading and extracting a cartridge, said cartridge having a primer in its base and an extractor groove around its base periphery, comprising,
(a) a bolt body having a firing end and a cocking en (b) means in the firing end of said bolt for ramming said primer for firing said cartridge (c) a fixed claw extended from the firing end of said bolt around a portion of the periphery thereof for engaging a portion of the periphery of said extractor groove (d) a plurality of pivoted claws extended from said firing end of said bolt into engagement with the remaining port-ions all around said extractor groove, said pivoted claws being movable radially away from said bolt (e) a receiver on the firearm for receiving said bolt (f) said receiver having an enlarged periphery beginning at about the point of loading in said receiver to accommodate the movement of said pivoted claws away from said extractor groove thereby to disengage them from said cartridge (g) and releasing means to move said pivoted clawsout of said groove at said enlarged periphery.
12. The bolt action defined in claim 11, said releasing means comprising (h) a sleeve slidable in said bolt (i) a lever extended from the pivot of each pivoted claw connected to said sleeve so as to swing the pivoted claw outwardly from the end of said bolt during retraction of the bolt (j) resilient means to urge said sleeve toward the firing end of said bolt to swing said pivoted claws.
13. The bolt action defined in claim 11 (f) said receiver having an ejection port on one side thereof for the ejection of the cartridge g) said fixed claw being so located as to be on the sideof the bolt adjacent to said ejection port during the retracting of the bolt (h) an ejector device in the firing end of said bolt lo- 7 8 cated generally opposite from the location of said 2,711,041 6/1955 Harvey 42-25 fixed claw to tilt the cartridge about said fixed claw 3,114,290 12/1963 Harvey et a1 8926 for ejection through said ejection port. FOREIGN PATENTS 19,8 1 t B 't References Cited by the Examiner 5 120 2? 32? giig gggf UNITED STATES PATENTS 427,587 5/1890 Mauser 42 25 BENJAMIN A. BORCHELT, Przmary Examiner. 1,294,454 2/1919 Hammond 42 16 SAMUEL FEINBERG, FRED C. MATTERN, JR., ,345,565 7/1920 Thompson 42-69 10 Examiners.