Abstract: A replacement centerfire bolt assembly for a rimfire rifle having a two-piece bolt with a detachable bolt head assembly and a method for modifying a bolt are disclosed. In accordance with the method, the bolt is first removed from the rifle, and then the rimfire bolt head assembly is removed from a remainder of the bolt. Next, a centerfire bolt head assembly is attached to the remainder of the bolt in place of the rimfire bolt head assembly. This centerfire bolt head assembly includes a bolt head having a central longitudinal axis, a cartridge end, a striker end, and an exterior size and configuration functionally identical to a size and configuration of a rimfire bolt head of the rimfire bolt head assembly. A bore is provided along the central longitudinal axis of the bolt head, with this bore including an enlarged recess adjacent the striker end. A one-piece centerfire firing pin is located in the bore of the bolt head, which firing pin is longer than the bore.

Abstract: The invention relates to a breech mechanism in a bolt-action firearm, consisting of a breech body (2) reciprocating in the receiver (1) and rotatable into locking position, and having on its front portion a locking lug (3, 4, 5) placed in three sectors. The locking lugs (4, 5) in at least two sectors have been formed in a breech mechanism provided with a parallel loading magazine (6) such that there are four guide surfaces (7, 8, 9, 10) limiting breech rotation between the receiver (1) and the breech body (2).

Abstract: A muzzle-loading firearm having a bolt, a receiver, a striker mounted in the bolt and a breech plug or other part of the receiver carrying a percussion cap in which the bolt has an extension engageable with the breech plug to prevent inadvertent engagement of the striker and percussion cap when the plug is not properly seated. Further, the bolt extension may prevent bolt locking when the plug is not properly seated.

Abstract: Bolt mechanism for an electronic firearm adapted to eliminate rearward axial motion of the bolt plug with respect to the bolt body on closing the bolt assembly.

Abstract: A mechanical tight cartridge casing release of the invention is preferably for inclusion with a large cartridge rifle bolt and includes a pivot mounting of a rifle bolt arm or handle to the bolt whereby, after the arm or handle is moved to an unlocked position, an application of a force to the arm or handle end wil pivot that arm or handle relative to the bolt surface such that an arm or handle forward shoulder engages a surface of the rifle receiver producing a lever action and providing a mechanical advantage to the force applied by an operator or shooter that arm or handle to "break loose" the spent cartridge casing from the barrel chamber, with the bolt to then be moved rearwardly to where the casing is ejected.

Abstract: A locking mechanism for a self-loading hand-held firearm includes a breech block carrier mounted for sliding movement in the longitudinal direction of the weapon and a breech block head which is rotatable about a longitudinal axis between a locked position and an unlocked position. The breech block head has a transverse control pin which is received in an oblique sliding guide formed in the breech block carrier. The sliding guide has first and second guide edge opposite to each other with different angles of inclination with respect to the longitudinal axis.

Abstract: A firearm having a reciprocating bolt assembly comprising a spring biased ejection port cover operatively connected to the bolt assembly to cover the ejection port when the bolt assembly is in the forward breech closed position, and which moves with the bolt assembly to uncover the ejection port when the bolt assembly is in the rearward breech open position.

Abstract: A firearm cartridge case capable of withstanding internal gas pressures of at least about 50,000 psi has two substantially cylindrical portions of significantly different diameters interconnected by a frusto-conical shoulder portion. The case has a ratio of its overall length to its diameter, at a location 1.25 inch from its base, of no more than about 4.2, giving it an unusually short, fat profile. The base of the case has a rim with an outer diameter substantially no less than the case diameter at the aforementioned location, to facilitate reliable feeding of the cartridge from the magazine. The corresponding firearm chamber which matingly accepts the cartridge is capable of withstanding internal gas pressures of at least about 65,000 psi.

Abstract: A loading lever assembly for a hand-operated firearm has a loading lever which can be pivoted from a released position in which it lies in the longitudinal direction of the weapon to an end-of-swing position on either side of the weapon. The lever is pivotally connected to a mounting strip on the breech block carrier by means of an oblong slot formed in an end of the loading lever and a pivot pin on the mounting strip. The oblong slot allows the lever to be moved from an end-of-swing position to an operation position in which the loading lever engages two end stops on the mounting strip to prevent the lever from swinging forward or rearward. A spring-loaded cam arrangement provides the restoring force for returning the lever to the released position from the end-of-swing positions.

Abstract: A repeater mechanism for a rifle that allows the breech to be pulled straight back, while the rifle remains in a supported stable position, for example, on the shoulder of the shooter. Breech, trigger assembly, pistol grip and a forward stock portion form a repeater mechanism that may be pulled back and moved forward along slide rails. A rearward stock portion comprises an opening for accommodating, in telescoping fashion, the forward stock portion when the repeater mechanism is pulled back. During the manipulation of the repeater mechanism, the rearward stock portion remains resting on the shoulder of the shooter and the shooter's hand, that manipulates the trigger, remains resting on the grip and thus, the stability of the rifle during quick manipulation of the repeater mechanism, is achieved.

Abstract: A sealing device for sealing the combustive gases of a caseless munition is mounted between a barrel and a firing chamber of a small caliber weapon. The sealing device includes a ring-shaped sealing element with a first end forming a radially extending sealing surface structured to press against the rear face of the barrel, and a second end includes an outwardly facing axially extending lip designed to press against an inner wall of the firing chamber. A cooling element reduces the rise in temperature of the sealing element, which comes into contact with the combustive gases.

Abstract: The present invention relates to an extractor for a firearm which incorporates internal extraction to withdraw a cartridge from the chamber of the firearm. The extractor includes an outwardly extending lip for engagement in a cavity defined in the rear of the cartridge. The cavity includes an inwardly extending flange and the lip of the extractor is positioned behind the flange during extraction. The extractor includes a first pivot point about which the extractor rotates in order to allow the extractor lip to enter the cartridge cavity. The extractor also includes a second pivot point about which the extractor exerts a positive rotational force to extract the cartridge from the chamber.

Abstract: A lever action firearm having a receiver, a hammer, a lever pivotal about a fixed point, a bolt and a link which link is pivotal on both the bolt and the lever. The pivotal lever includes first surface means to engage second surface means on the hammer to cause the hammer to be cammed back during unloading. The lever, link and bolt are configured such that when they are in the fire position and are subjected to forces of firing they function as a joint lock to prevent unloading of the bolt and lever. Locking surfaces on the receiver and bolt strengthen the joint lock at the moment of firing.

Abstract: A firearm frame constructed of plastic material having slide rail guidance members in the forward, central and rear portions of the frame. The frame is useful with a barrel unit which is cammed back and down by slide reciprocation and by a cam block which with barrel movement being arrested by the walls of a frame cavity. Forces and energy created in arresting such back and down movement of the barrel and block is transferred to the frame by the block hitting the frame cavity. A slide stop pin passing through openings in the frame and cam block also assist in transferring energy to the frame. Forces causing the slide to move upward during the arresting of barrel and block is prevented buy the rail guidance members. The trigger rotates about a trigger trunnion located in such frame cavity below the cam block.

Abstract: A firearm bolt prepared from an alloy of tungsten, nickel and iron having a density of about from 14.1 g/cc to 18.0 g/cc. The alloy preferably also contains at least one of molybdenum, cobalt, rhenium, tantalum and gold. The alloy is preferably manufactured by standard powder metallurgical techniques followed by a liquid phase sinter and vacuum anneal. The bolt can also be manufactured using solid state sintering. The bolt can also be manufactured by mechanically working the material after sintering, after annealing, or after both sintering and annealing.

Abstract: A portable firearm employs a frame and an upper mechanism having a bolt and a sliding hammer. A barrel assembly is supported on the frame and has an axis, a muzzle and a breech. The sear transversely straddles the barrel assembly and can project above its axis for restraining the hammer. A trigger mechanism employs a reciprocatable member coupled to the sear for selectively operating the sear automatically or semi-automatically. An intervening member is mounted to reciprocate transversely to the axis of the barrel assembly. This intervening member can retract upon the hammer moving against the intervening member. The intervening member is bifurcated to straddle and reciprocate transversely to the axis of the barrel assembly.

Abstract: An in-line muzzle-loading firearm in which the firing pin is cocked by a bolt action permits the use of a stronger firing pin spring, a firing pin of reduced mass, and reduced firing pin travel, resulting in reduced lock times.

Abstract: A semi-automatic pistol includes a polymeric frame, a barrel secured to the frame medially of its front end and rear end. A slide is slidable relative to the frame without direct engagement therewith. A retainer and guide member is removably secured adjacent a rear portion of the frame and includes a pair of outwardly extending guides. Each of the guides slidably fits within one of a pair of opposing inwardly facing longitudinal grooves. Each of the grooves is disposed along opposed inner surface portions of the slide for retaining and guiding the slide in generally parallel spaced relation to the frame. The pistol includes a second retainer and guide means adjacent the front end and includes, at least in part, a generally circular aperture in a depending front wall of the slide and wherein the muzzle end of the barrel extends through the aperture. The aperture has a predetermined chamfer to enable the slide to disassembled from the pistol after the first retainer has been disconnected from the frame.

Abstract: A breech bolt lock-up device for a firearm absorbs linear inertial forces and utilizes the absorbed inertial force to linearly cycle the firearm. The lock-up device includes an inner lock sleeve and an outer lock sleeve. A locking device will releasably lock the inner lock sleeve with the outer lock sleeve. A cam member is axially aligned with the inner lock sleeve and the outer lock sleeve. The cam member is engagable with the locking device for releasing engagement between the inner lock sleeve and the outer lock sleeve. The cam member linearly reciprocates relative to the gun barrel. A cam spring is provided for storing linear inertia energy when the cam member moves forward. A recoil spring will store linear inertia energy when the cam member moves rearwardly.

Abstract: An automatic weapon includes a housing; a bolt movably received in the housing; a weapon barrel replaceably received in the housing and having a recess; and a locking member movably supported in the housing to assume locking and releasing positions. In the locking position the locking member projects into the recess for locking the weapon barrel to the housing and in the releasing position the locking member is withdrawn from the recess. There are further provided a spring for urging the locking member into the releasing position; a shaft rotatably supported in the housing and a cam secured to the shaft for rotating therewith as a unit and for contacting the locking member. The cam has a first angular position in which it holds the locking member in the locking position and a second angular position in which the spring holds the locking member in the releasing position.

Abstract: A manually actuated rifle which maintains the aesthetics of a semi-automatic rifle, but which is incapable of semi-automatic or automatic fire. A piston guide member is provided which has at least one aperture therein for preventing actuation of the action by gas pressure.

Abstract: A gun equipped with a mobile handshield for controlling gun loading, includes a casing (1), a barrel (2) mounted onto this casing (1) and extending axially, a mobile part (6) extending in the axial direction in relation to the casing (1) for controlling a loading mechanism mounted in the casing. The handshield (5) is fixed to this mobile part (6) and is guided by guiding means (11-12), such that the handshield (5) is fixed in a tilting manner to the mobile part (6). The guiding means (11-12) of the handshield (5) are such that they make the rear end of the handshield (5) tilt downwards when it is moved backwards, such that the outer rearward end of the handshield (5) can move over a distance under the casing (1).

Abstract: An improved bolt carrier for a gas operated automatic or semi-automatic firearm of the AR15 or M16 type having a substantial increase in the number and area of lands in the forward end of the bolt carrier. This results in increased accuracy of the firearm and makes the action smoother and more consistent.

Abstract: In the breech mechanism for a firearm the receiver (2) attached to the barrel has a radially inwardly directed conical locking shoulder (16). A breech head (9) and a locking sleeve (7) are arranged in a slider (3) slidable relative to the breech housing (1) in the barrel direction. The locking sleeve (7) is divided into a plurality of spring tongues (7b), each of which carries a locking element (13) with radially inwardly and outwardly directed cone sections. A spreading cone is arranged in the vicinity of the front end (9a) of the breech head (9) and cooperates with the locking elements (13). An actuating lever (18) is arranged on the slider, connected to a pivot shaft (17). The pivot shaft (17) is connected to a locking lever (19). A two-armed intermediate lever (20) is pivotally mounted on the slider (3) behind the locking lever (19), pivoting about an axis (20a) parallel to the pivot shaft (17) and cooperating with an abutment (22) arranged on the breech housing (1).

Abstract: A lock-up device for a firearm which utilizes a ball and cam arrangement to interlock two members. The interlocked members include ball engagement surfaces which are curved so that a substantial portion of the ball surface is in contact with the engagement surfaces. The lock-up device disposed in a firearm absorbs inertia forces and utilizes the absorbed inertia force to cycle the firearm.

Abstract: A bolt assembly is provided for a double-barrel firearm, such as a rifle or a shotgun. The bolt assembly is adapted to fit in the receiver of the double-barrel firearm. The bolt assembly comprises a bolt body which connects to first and second breech bolts, and which also couples to a bolt collar. The bolt collar has a bolt handle for operating the bolt assembly. The bolt body and breech bolts have recesses for accepting first and second firing pin assemblies. The firing pin assemblies include first and second cocking pieces, which are both cocked by means included in the bolt collar. Once cocked, the cocking pieces can be released independently of each other for firing using trigger means. Pulling the bolt assembly rearwards ejects the fired cartridges through an ejection port on the receiver. The receiver also includes a cartridge injector port which couples to a magazine capable of storing additional cartridges.

Abstract: A bayonet-connector-like breech lock has a breech housing and a breech block with at least two radially projecting locking components. The enlarged region needed to rotate the locking components takes the form of an annular space wherein a locking sleeve is fitted to rotate between an open and a locked end position. The locking sleeve has a widened section for each locking component aligned with a widened part of the breech block bore in the open end position. The annular space is completely filled by the locking sleeve and the pushed-in breech block.

Abstract: The breech mechanism for a firearm is provided with a breech housing, a locking head connected to the barrel and having a radially inwardly directed conical locking shoulder oriented rearwardly of a cartridge carrier, and a substantially cylindrical breech block movable relative to the breech housing in a direction toward and away from the barrel. A locking sleeve concentrically surrounding the breech block and axially slidable relative thereto to a limited degree, is divided at its front end by a plurality of longitudinal slots into a plurality of spring tongues and carries at the free, front end of each spring tongue a locking element formed in one piece therewith and in the form of an annular segment. Each locking element has a radially outwardly directed cone segment bearing on the locking shoulder in a locking position and having on its front end a radially inwardly directed cone segment with which it bears on a spreading cone arranged in the vicinity of the front end of the breech block.

Abstract: A rack and pinion system for a lever action firearm provides the rack element as a floating gear and includes a cam lever extension of the lever member. The cam lever extension applies rearward force directly to the bolt body and compresses a spring between the lever member and the rack element. After the bolt breaks free from the locking lugs, force is applied to the rack element by the lever member through the spring, whereby to complete the rearward movement of the bolt.

Abstract: An automatic machine pistol is provided, which is not subject to fouling, which is compact and light while incorporating a pneumatic recoil buffer, which resists muzzle climb, and which can be accessed and cleaned without disassembly. The machine pistol is comprised of a reciprocating bolt within a housing of the pistol. The reciprocating bolt is carried within the housing on four rails by eight roller bearings. No sliding contact is made between the bolt and any other portion of the pistol. A portion of the high pressure gas from the barrel is bled through a bleed hole in the barrel block or barrel into a gas port tube which is telescopically inserted into the bolt. The gas port tube delivers the portion of the discharge gas in a forward direction in opposition to the motion on recoil. An upwardly directed nozzle is communicated to the receiving bore within the bolt.

Abstract: A receiver assembly for a firearm slidably and rotatably carries a bolt having a non-rotating cartridge extractor-guide at the forward end which allows the bolt to rotate relative thereto and the bolt head has locking lugs which engage a locking surface in the forward or barrel end of the receiver when the bolt is in the firing position. A flexible feeding ramp in the firing chamber surrounds the extractor and serves as a cartridge guide and pre-loads the bolt axially in the firing position. A firing pin carrier assembly provides axial center line absorption of the firing mechanism forces while providing an off center firing pin tip required for rimfire ammunition. During the initial firing sequence the feeding ramp absorbs vibrations caused by the moving components of the firing mechanisms and the impact of the firing pin and the subsequent shock of ignition, and bullet movement.

Abstract: A brech bolt for use in a gas powered gun features a plunger operated ball detent for releasably retaining the bolt in a breech closed position. A method is disclosed for assembling the ball detent.

Abstract: A bolt action rifle having a flange projecting from a ring captured between the barrel and the receiver, the flange mating with the undercut in the bolt needed to pass the cartridge during loading into the grip of the extractor to achieve controlled round feeding, the flange serving to support the cartridge during detonation in the area of the cartridge which otherwise would be unsupported.The mating of the flange with the undercut of the bolt requires a non-rotating bolt. An inner bolt sleeve is provided, axial movement thereof serving to control rotating locking lugs at the front of the bolt which lock the bolt during detonation.

Abstract: A cocking-bar, target-framing and range-finding, carrying, hanging, and standing device for weapons and firearms, comprises, in its preferred embodiment, a rigid handle of triangular-frame configuration constructed of any ferrous or nonferrous metal alloys or material of similar strength and enduring toughness to withstand repetitive use. This cocking bar is an accessory, adapter and/or replacement device for existing encumbering cocking knobs, cocking handles, cocking bolts or other cocking devices on weapons and firearms. By means of a superior hand-to-surface-area ratio, this device's features are designed to provide augmentation and enhancement of the proficiency of the user's performance in activating the bolt-actuating mechanisms of weapons and firearms in facilitating cocking. The device also serves well in target location, framing and range finding by means of provides striae.

Abstract: A firing mechanism having a trigger operated breech block. A crank, connected between the trigger and the breech block, has a first camming surface for moving the breech block forwardly and locking it in a firing position, and a second camming surface for cocking and releasing the firing pin during the breech block's forward movement.

Abstract: A bolt assembly for a firearm is constructed with three locking lugs, one of which is oriented down in unlocked condition as it is withdrawn past the magazine of the firearm. The body of the bolt is of reduced diameter with respect to the bolt head which carries the locking lugs. A cartridge depressor is mounted in association with the bolt body to effectively increase the diameter of the bolt body in the vicinity of the magazine to that of the bolt head.

Abstract: The present invention relates to a locking lug insert which is inserted into the locking lug recess of a bolt action receiver. The insert defines a central aperture aligned with an elongated chamber in the receiver and one or more cut-out portions opening into the central aperture, one cut-out aligned with each locking lug groove. The cut-out portions are equal in number to the number of locking lug grooves formed in the receiver. The cut-out portions are sized so as to accommodate the locking lugs of the bolt when the bolt is in its closed position. The insert is caused to rotate in the locking lug recess when the bolt rotates, due to the interengagement of the locking lugs, with the cut-out portions.

Abstract: A breech bolt firearm in which the bolt is mounted turnably but axially immovable in a guide sleeve is improved by placing a projection on part of the bolt which when aligned with a longitudinal recess provided on the sleeve allows dismantling of the breech bolt mechanism. Also a safety is provided which latches both the firing pin nut and the bolt handle.

Abstract: A simple to manufacture high pressure rechargeable ammunition cartridge comprising a hollow pressure casing 20 providing a gas storage space 19 to hold compressed gas therein, with a discharge passage 25 in a front part of said casing said gas storage space; an actuation passage 24 extending into said casing from the rear; a valve opening 52 at a front end of said actuation passage, and a valve member which has a normal position wherein it closes said valve opening and blocks said discharge passage, and is movable bodily forwards as shown from said normal position to open both said valve opening and said discharge passage to allow gas to escape from the pressure casing directly through both of said passages to drive a missile. The valve member may be modified so as to be dischargeable from the cartridge and may form part of a missile.

Abstract: The invention relates to a device in a repeating rifle with a cylinder bolt mechanism with a receiver and a bolt, comprising a bolt body with a mainspring and a firing pin, a rotatable bolt head, a handle, and in the receiver studs or some corresponding locking means interacting with the bolt head. A lockable lock (15) is arranged in the cylinder mechanism, said lock when in its locking position preventing the bolt head (9) from being turned from its position in engagement with said studs or corresponding locking means (4) in the receiver (2), thereby preventing the gun from being opened, i.e. the bolt (1) from being moved rearwards in the receiver (2).

Abstract: A firearm (10) adapted for blowback operation has a receiver incorporating a longitudinally reciprocatable bolt assembly (24) having an inertia firing pin (40) which is movable between retracted or recoil and battery positions in the receiver (14). A trigger (68), including a sear (72), is pivotally mounted in the receiver. A hammer (74) is pivotally mounted in the receiver in such a manner that movement of the bolt assembly from the battery position to the recoil position urges the hammer into a cocked position. The hammer includes a first sear abutment (82) to engage the sear on the trigger, a second sear abutment (84) and a stop abutment (86). A disconnector (76) is pivotally mounted on the trigger pin (70). The disconnector includes a hook sear abutment (88) on an intermediate portion which is adapted to engage the second sear abutment on the hammer when the trigger is in a depressed position.

Abstract: This invention relates to a firearm and more particularly to a firearm having a bolt action in which a bolt is arranged for axial and rotational movement in a receiver and an extractor system operable in combination with the movement of the bolt relative to the bolt receiver. The bolt includes lugs having a locking surface which engages a locking wall formed on a cooperating lug on the receiver when the bolt is in the firing position. Both the locking surface and locking wall are arranged at cooperating angles and are conically shaped so as to insure that the axis of the bolt and receiver will be concentric when the bolt is locked in the firing position. In the event of a cartridge rupture the angle of the locking wall causes some of the forces generated by the rupture to be diverted at an angle from the axis, thereby minimizing the shearing stresses on the receiver lugs.

Abstract: A bolt action rifle of simplified, economical and durable construction resembling an assault rifle is disclosed. An elongated action tube connected between a barrel and stock houses and guides the bolt in all positions of the latter. A unified housing member attached to the action tube defines a magazine having communication with the interior of the action tube and a mounting for a simplified firing and safety mechanism involving a minimum number of parts.

Abstract: A gun is provided which is capable of firing a variety of projectiles driven by a variety of propellants. The barrel may be readily disconnected from the stock of the gun. The breech is designed to receive a standard gauge shotgun shell. Inserts are also provided with the same general configuration of a standard gauge shotgun shell, and when placed into the breech, allow the gun to fire a variety of projectiles. Inserts are provided which allow the gun to fire both center fire and rim fire rounds through a bore in the insert. A rocket insert is also provided which contains a smooth bore and is capable of firing rockets. An inertial firing pin is provided, which operates in conjunction with a floating breech plate. The floating breech plate is used in the firing of compressed gas bottles. A dual action spring drive is provided which is used to provide the necessary force to drive the firing pin and which also absorbs a portion of the recoil.

Abstract: A unitary bolt and chamber adapter for field replacement, without tools, of the conventional bolt assembly of rifles of the type M16 and AR-15 provides for the use of conventional .22 caliber long rifle rimfire ammunition in the rifle instead of the larger conventional centerfire ammunition. The bolt functions in semiautomatic fire by conventional blowback action. Through cooperation with an improved .22 caliber rimfire magazine adapter, the breech automatically remains open after firing the last round from the magazine. The bolt guide rails are flexibly attached to the chamber providing for reliable operation in a larger number of rifles. A spring actuated forward locator on the bolt assembly keeps the adapter seated in the rifle chamber, compensating for differences in gun receiver lengths. An undercut bolt face provides the positive extraction of a double extractor system with a single extractor, and a groove-and-land chamber adapter provides reliable operation with good and poor quality ammunition.

Abstract: A unitary bolt face and firing pin device for firearms consisting of a self-adjusting head space block on the front of the bolt assembly facing the chamber in firing alignment with the primer of a cartridge inserted into said chamber, the face of said head space block having integrally formed thereon a firing pin for impacting with said cartridge primer when said bolt assembly is closed against said chamber.

Abstract: An inactivating selector arrangement for a bolt action firearm for inactivating the sear and trigger and for inactivating the bolt. The multiposition selector is rotatable to a first position to restrain the sear-trigger; to a second position to restrain both sear-trigger and bolt and to a third position in which neither sear-trigger nor bolt is restrained.

Abstract: In a firearm with a cylinder bolt mechanism, a locking chamber (27) is arranged in a space in the barrel between the rear end of the barrel and the rear end of the cartridge chamber for a bolt tip (28) on the bolt. Behind the locking chamber in the barrel is arranged a separate locking ring (23) between a stop (25) in the receiver and the rear end of the barrel. The locking ring is provided with lugs and grooves, and the bolt head is provided with corresponding claws which are able to pass through the grooves in the locking ring and to be rotated into the locked position ahead of the lugs in the ring. By introducing the bolt complete with the bolt head into the barrel and locking it securely in this position, it is possible to achieve greater accuracy because the bolt head acts as a stiffening connection between the barrel and the receiver, so that these components of the firearm are unable to move relative to each other as the result of oscillations in the barrel when the cartridge detonates.

Abstract: A trigger mechanism wherein the trigger moves about a first fulcrum for sear release of the firing pin and a second fulcrum for further retraction of the sear away from the bolt assembly to permit rearward removal of the latter. The trigger is configured to provide two spaced apart pivots which coact with the underside of the rifle receiver. Sear retraction for bolt assembly release is accomplished with minimal trigger movement.

Abstract: A firearm bolt comprises a base having a plurality of outwardly radially ending lugs. Transition surfaces between adjacent lugs are each concavely curved toward the base so that each lug has a broad base area connecting the lug to the base.