Abstract: Firearms and bolt carriers having a bolt head including a bolt head axis and a plurality of locking lugs, wherein at least two recesses having a radius, measured with respect to the bolt head axis, are formed on the bolt head between at least two adjacent locking lugs. To improve the guidance of the bolt head, at least two centering ramps, which are designed obliquely to the bolt head axis and protrude in the axial direction toward the rear up to a central radius that is greater than the radius, for self-centering the bolt head during the bolt process are formed in the region of the recesses.

Abstract: A breech for a pistol including a barrel, which includes at least one barrel block and one chamber, as well as a slide and a breech guide, which is designed to move on a guide rail of a frame of the pistol and on which a socket having a breech face is formed. In order to increase the mechanical stability, the barrel block includes at least one recess on each side, which interacts with centering rails that are provided on the inside of the breech guide and are formed to be complementary to the recesses in terms of form and function.

Abstract: The invention relates to a firing pin safety of a firearm, which firearm comprises a firing pin safety, a hammer, a bolt, a bolt carrier, and a firing pin, in which the firing pin safety comprises a safety lever mounted on a bolt carrier of the firearm, which firing pin safety is configured to control movement of a firing pin of the firearm. The safety lever and the hammer are integrated functionally, the safety lever is turnable and has three main positions: a basic position, in which position the safety lever retains movement of the firing pin to a primer of a cartridge and from inside the bolt, a release position, in which the safety lever actuated by the hammer releases movement of the firing pin towards the primer of the cartridge but not from inside the bolt, and a dismantle position, in which position the safety lever of the firing pin safety can be dismantled and the firing pin can be removed manually from inside the bolt of the firearm without tools.

Abstract: A method of assembling a bolt handle to a bolt assembly of a firearm includes inserting the bolt handle through a handle opening defined by a bolt body. A distal end of the bolt handle is inserted through the handle opening until the distal end extends past an outer perimeter of the bolt body. At least a portion of a bolt shroud is inserted through a first portion of an aperture defined by the bolt handle. A force is applied to the bolt shroud while the bolt handle is retracted within the handle opening of the bolt body so that the bolt shroud is positioned within a second portion of the aperture. The bolt shroud is held in connection with the bolt handle when the bolt shroud is positioned within the second portion of the aperture to secure the bolt handle to the bolt body.

Abstract: Firearms including a secured firing pin retaining pin, the firearms having a barrel, a sliding block, a bolt head, a firing pin with a flange-like collar, a firing pin retaining pin with a safety device, and a weapon median plane. For facilitating handling, it is provided that the firing pin retaining pin is slidably mounted normally to the weapon median plane in a retaining bore, that it is designed as one piece and to be rotationally symmetrical with a head and a pin end and has two annular grooves. A locking pin mounted in a spring-loaded manner in the sliding block is designed such that, depending on the position of the firing pin retaining pin in the retaining bore, it can optionally engage in one of the annular grooves, which correspond to a holding position and a release position for the firing pin, respectively.

Abstract: A bolt action firearm has a frame defining a bolt passage, an elongated bolt assembly configured to reciprocate within the bolt passage, the elongated bolt assembly defining a firing pin passage, a firing pin assembly received in the firing pin passage, a bolt handle having an inner end configured to removably engage the firing pin assembly and an opposed free end, the bolt handle inner end having opposed spaced-apart prongs defining a bolt handle channel, the bolt handle defining a pocket associated with the bolt handle channel, the firing pin assembly having a handle engagement portion having a first section configured to be received in the bolt handle channel, and the firing pin assembly having a second section adjacent to the first section such that when the second section is biased into the pocket, the firing pin assembly is secured against passage through the bolt handle channel.

Abstract: A bolt assembly has a rear block configured for connection at the rear end of the bolt passage, a bolt carrier configured to reciprocate in the bolt passage, a support element between the rear block and the bolt carrier, a first spring between the support element and the rear block, the bolt carrier defining a bore, the support element including a guide rod slidably received in the bore, and a second spring encompassing the guide rod, having a rear end abutting the support element, and a forward portion received in the bore. The bolt carrier may include a bolt carrier body, and the bolt carrier may include a weight portion movably connected to the bolt carrier body. The weight portion may define a through hole receiving an intermediate portion of the guide rod and an intermediate portion of the second spring.

Abstract: A surgical instrument includes a jaw tool with two branches that can be closed for grasping tissue. In order to transmit the closing force to at least one branch, the branch is coupled with a preferably manually actuatable pull/push element, and, for coupling, an actuating pin that supports a sleeve interacts via the sleeve with a coupling track, in which case the sleeve rolls off the coupling track. In this manner, any deformation, abrasion or burr formation on the coupling track is prevented to such an extent that, even after numerous closing movements of the branches, the branches can still be actuated unimpaired by any wear of the coupling track and the actuating pin, respectively.

Abstract: System for a multi-caliber self-loading action. Specifically, the system is comprised of a multi-position locking assembly and a self-regulating gas assembly. The multi-position locking assembly is comprised of a bolt carrier, a spring, a bolt, a lock, and a cam assembly. The cam assembly will interface between the bolt carrier and the bolt to rotate the bolt through the bolt carrier. The lock will interface with the bolt, to lock the bolt in at least one locked position based on the caliber of the round inserted. The self-regulating gas assembly directs gas from the gas regulation to at least one piston cup, which will then cause the piston to act on the multi-position locking assembly.

Abstract: A firearm includes a barrel having a breech end. A receiver is engaged with the breach end of the barrel and defines a chamber. A vent path is through the barrel downstream from the breech end. A latch is downstream from the vent path. A bolt is at least partially inside the chamber. The bolt has a locked position to prevent the bolt from moving away from the breech end of the barrel and a released position that allows the bolt to move away from said breech end of the barrel.

Abstract: A self-locking bolt assembly is provided having a short stroke allowing the assembly to be contained within the receiver. The assembly has a base plate, a recoil rod with a spring, a bolt body, a bolt and a locking mechanism. The bolt is internally (i.e. lockable onto itself) lockable when the bolt is in battery. The locking mechanism, for example, can be a roller bearing, a lever lock, a cam rotary lock or a roller. The locking mechanism engages to recoil rod and prevents rearward motion of the bolt. Blowback and reciprocation of the bolt are temporarily delayed after a shot is fired until after the bolt is unlocked. Rearward movement of the bolt body due to inertia causes the locking mechanism to be disengaged to unlock the bolt and to allow for reciprocation of the bolt.

Abstract: The invention relates to a breech system for a firearm, having a bolt receiver and a bolt; the bolt receiver is embodied in the form of a hollow cylinder at least with engagement means protruding radially inward and there is also at least one bolt head, which has outward-protruding engagement means that correspond to the inward-protruding engagement means; the bolt head is supported in rotary fashion on a bolt carrier and there is also a bolt body, which is able to slide on a bolt head shaft of the bolt head, and between the bolt body and the bolt carrier, there is at least one compression spring, which tends to move the bolt body in the direction toward the bolt head; and on the bolt head shaft and on the bolt body, there are means that produce a rotation of the bolt head when the bolt body is slid on the bolt head shaft.

Abstract: A firearm for firing cased telescoped (CT) ammunition cartridges that includes a split chamber configured to fully support a CT cartridge when it is fired, and that includes i) a dynamic rear chamber portion defining a pocket in a face of a bolt, and ii) a static front chamber portion that is integral to the barrel and separate from the bolt. A cartridge extraction mechanism engages the CT cartridge prior to the CT cartridge being fired, and holds the CT cartridge in the pocket in the bolt face as the bolt moves rearward to pull the CT cartridge out of the static front chamber portion and into an ejection position. An ejector is operable to eject the CT cartridge from the pocket in the face of the bolt when the CT cartridge reaches the ejection position.

Abstract: A bolt carrier that facilitates seating a full magazine in the lower receiver of a magazine-fed gas-operated firearm with the bolt in a closed position. The bolt carrier includes a recessed portion that aligns with a top cartridge in a full magazine when the bolt carrier is in a closed position to provide additional space for the full magazine to be inserted into the magazine well. The recessed portion provides a space for the top cartridge to nest when the bolt carrier is in the closed position.

Abstract: A firearm as disclosures herein comprises a main receiver body, a barrel, a breech bolt structure, a buffer assembly, a trigger group assembly, a bolt catch and at least one of an auto-sear, a magazine adapter and a breech bolt anti-rotation structure. The main receiver body is preferably of a monolithic construction whereby the handguard and breech bolt carrying bore can be manufactured from a single piece of material. The auto-sear is tripped by engagement with a buffer of the buffer assembly. The magazine adapter has an exterior surface structure engaged with a mating interior surface structure of a magazine well space of the main receiver body. A distal end portion of the breech bolt anti-rotation structure is engageable by the buffer for limiting forward travel of the buffer when the barrel is detached from the main receiver body.

Abstract: A firearm is described herein. The firearm comprises a receiver assembly adapted to receive a cartridge, a bolt assembly including a firing device operable to fire the cartridge, a barrel adapted to receive the projectile after the cartridge is fired, and a gas assembly including a gas tube. The receiver assembly includes an upper receiver portion, a lower receiver portion, and an upper receiver cover. The upper receiver portion defines a longitudinal axis, and an indexing slot operable to receive the gas tube. The upper receiver portion includes at least one integrated exterior track extending generally parallel to the longitudinal axis adapted to slidably couple with the upper receiver cover and a plurality of interior tracks extending generally parallel to the longitudinal axis adapted to slidably couple with the bolt assembly. The upper and lower receiver portions are pivotally connected to one another.

Abstract: The present disclosure generally relates to a bolt catch device that prevents the bolt of a bolt carrier assembly of a firearm from moving to its forward position so as to prevent the firearm from being discharged until the user manually moves the bolt catch. The bolt catch is mechanically coupled to the selector of the firearm via a linkage, so that the bolt catch can be moved by way of the selector. This feature can prevent a self-loading firearm that otherwise could function on a semi-automatic basis from operating in such a manner.

Abstract: The invention relates to a breech system for a firearm, having a bolt receiver and a bolt; the bolt receiver is embodied in the form of a hollow cylinder at least with engagement means protruding radially inward and there is also at least one bolt head, which has outward-protruding engagement means that correspond to the inward-protruding engagement means; the bolt head is supported in rotary fashion on a bolt carrier and there is also a bolt body, which is able to slide on a bolt head shaft of the bolt head, and between the bolt body and the bolt carrier, there is at least one compression spring, which tends to move the bolt body in the direction toward the bolt head; and on the bolt head shaft and on the bolt body, there are means that produce a rotation of the bolt head when the bolt body is slid on the bolt head shaft.

Abstract: The invention relates to a firearm including a component carrier, a barrel having a cartridge chamber for accommodating a cartridge, and a slide that is supported on the component carrier in a longitudinally moveable manner and has a breech block for the barrel and a firing device for the cartridge. The slide bears an extractor for extracting a fired cartridge from the cartridge chamber. An ejector is supported on the slide in a longitudinally moveable manner, which ejector protrudes from the side into the extraction motion path of the cartridge and lies against a stop formed on the component carrier in the end phase of the rearward motion of the slide. The slide, together with the ejector, can be modularly replaced with a second slide having no ejector. For the second slide, said stop assumes the ejector function.

Abstract: Components of a firearm having a bolt with locking lugs improve shooting accuracy, due to increased coaxial alignment between the bolt, the cartridge, the receiver, and/or the barrel of a firearm. The receiver inner surface is shaped for lug-cleaning and for close tolerance/mating with the lugs only in the locked position and also with a non-threaded, axial surface of the barrel. Thus, the mating surfaces that are instrumental and/or that mainly control coaxial alignment of the receiver, bolt, and barrel are located between the lug stops and the threaded end of the receiver. The lugs may be axially curved or otherwise axially non-linear to tolerate dirt and other debris in a field environment.

Abstract: A firearm comprising a barrel assembly, forward receiver, and receiver brake. The barrel assembly comprises a barrel, compression spring, gas tube, and front and rear bushings. The gas tube is situated around the barrel between the front and rear bushings and is not attached to the barrel. The compression spring is situated around the barrel between the front and rear bushings and inside of the gas tube. The front and rear bushings are fixedly attached to the forward receiver. The barrel comprises a gas port that is covered by a gas regulator and is in fluid communication with a gas chamber situated between the front bushing and the gas regulator, which is fixedly attached to the barrel. The receiver brake is fixedly attached to the forward receiver on its distal end.

Abstract: A conversion set for a firearm having a grip and a slide locked by a moveable barrel and including an ejecting opening is disclosed. To permit timely opening of the slide when using a replacement barrel which does not lock the slide, the conversion set for use of a replacement barrel which does not lock the slide includes a jacket which may be connected to the slide in a detachable, form-fitting manner. The jacket has a defined mass for the predetermined movement of the slide following a shot being fired.

Abstract: A gas operating system for engaging the automatic or semi-automatic action of small arms. The system has a short, displaceable cylinder with a gas block ring secured thereto, a short, fixed piston attached coaxially to a gun barrel, and a single locking nut, advantageously in the form of a threaded flash suppressor. The piston includes gas block rings at its rearward exterior surfaces. The cylinder has a short stroke between radial forward and rear stops fixed on the barrel, which short stroke may be finely adjusted by threaded axial displacement of the rear stop. Pressurized combustion gas from fired ammunition fills a gas chamber formed by the interiors of the piston and cylinder, the gas entering through radial ports in the barrel. The system may be machined and assembled/disassembled with ease and may be readily adapted for employment in any small arms. The system may be fine tuned for usage with a wide spectrum of ammunition.

Abstract: A gas cycling firearm comprising a barrel having a breech end, a muzzle end, an inner surface defining a bore having a bore axis, and an outer surface, wherein the muzzle end is spaced a length L from the breech end, the barrel further having a port providing a fluid path between the bore and the outer surface, the port having an axis that intersects the bore axis at a position P from the muzzle end, where P is less than or equal to ? L; and a gas flowpath extending between the gas port and the piston system, the gas flowpath having a length G and a volume V, wherein G is greater than ? L.

Abstract: A cam pin system, includes a cam pin comprising a first cylindrical portion having a first length and a first diameter and a second cylindrical portion concentric with the first cylindrical portion and having a second diameter larger than the first diameter, the second cylindrical portion comprising a through-hole to accommodate the passage of a firing pin. The system includes an end plate detachably connected to the first cylindrical portion of the cam pin, a cylindrical bushing encircling the first cylindrical portion and having an outside diameter approximately equal to the second diameter and a bushing length approximately equal to the first length, and lubricant between the cylindrical bushing and the first cylindrical portion. The cam pin system is configured so that the cylindrical bushing can rotate freely about the first cylindrical portion.

Abstract: A bolt assembly for a firearm such as an auto-loading or pump action shotgun includes a bolt body, bolt carrier and a bolt head. The bolt head is received within the bolt body and is rotatable within the bolt body to lock the bolt assembly into battery prior to firing the weapon, but does not extend from the bolt body during such rotation. The bolt carrier translates axially relative to the bolt body so as to cause rotation of the bolt head. The extractor for the firearm can be pivotally attached to the bolt body, while the ejector further can be integrated into the bolt assembly for engaging and ejecting a shell or cartridge after firing.

Abstract: Disclosed is a bolt assembly that may include several lands that extend along the forward end of the bolt assembly that occupy only about 1 percent to about 12 percent of the surface area of the forward end. Also disclosed is a bolt carrier that defines a cam path that includes an increased unlock dwell time of approximately twice the unlock dwell time provided by a cam path shaped like a standard M-16 cam path. Also disclosed is a bolt carrier that includes a protrusion at a forward end of the bolt carrier with a bore that extends through the protrusion and the bolt carrier at a substantially constant bore diameter, where the protrusion is sized to be received in the barrel extension extends approximately one hundred thousandths of an inch from the end of the bolt carrier.

Abstract: Rotary lug breeches and weapons including such rotary lug breeches are disclosed. An example rotary lug breech includes a bolt carrier. Wherein when releasing the bolt, a cam section of a receiver converts a releasing motion into a screwing motion to release a cartridge. During the screwing motion, a first stud surface interacts with the cam section. During a locking process, the first stud surface engages the cam section to perform a pre-control process that rotates a control pin in a slot from a releasing position in which an advancement of the bolt carrier exerts substantially no torque on the bolt, to a control position in which a first slot surface of the slot interacts with the control pin. When the bolt carrier moves forward, the bolt carrier exerts a torque on the bolt to enable the bolt and the bolt carrier move relative to one another.

Abstract: A cam pin system, includes a cam pin comprising a first cylindrical portion having a first length and a first diameter and a second cylindrical portion concentric with the first cylindrical portion and having a second diameter larger than the first diameter, the second cylindrical portion comprising a through-hole to accommodate the passage of a firing pin. The system includes an end plate detachably connected to the first cylindrical portion of the cam pin, a cylindrical bushing encircling the first cylindrical portion and having an outside diameter approximately equal to the second diameter and a bushing length approximately equal to the first length, and lubricant between the cylindrical bushing and the first cylindrical portion. The cam pin system is configured so that the cylindrical bushing can rotate freely about the first cylindrical portion.

Abstract: An anti-rotation feature incorporated between a cotter pin and a sub caliber action device installable within an upper receiver of a firearm. A receiver plate exhibits a notched interior for seating a bolt in reciprocating fashion. A chamfer formed in a side of the bolt intersects a length extending channel of the bolt for seating within the notched interior. The chamfer seating a head of the cotter pin to prevent rotation during bolt travel. A rearward support sleeve seats an opposing guide rod associated with the receiver plate and in order to maintain the bolt assembly. A firing pin exhibits a notch at a location along its shaft and, upon installation within an interior aperture of the bolt, is retained in position by the cotter pin. The firing pin is configured so as to exhibit a reduced diameter end projection upon which is supported a coil spring.

Abstract: A firearm having a bolt carrier comprising an operating rod slot that is open at an end of the bolt carrier. The bolt carrier also includes a cam slot extending from the operating rod slot. The firearm includes a bolt having a protrusion extending from the bolt which enters and is movable within the cam slot. The firearm further includes an operating rod comprising a piston and a foot. The foot is disposed within the operating rod slot to prevent the separation of the bolt from the bolt carrier and to connect the operating rod to the bolt carrier.

Abstract: A bolt action firearm includes a bolt assembly with a bolt body having an outer surface defining a longitudinal guide channel extending along a length of the bolt body from a rearward end to a forward end. A receiver defines a central longitudinally extending bore for accommodating the bolt body. A bolt guide is configured to be coupled to the receiver. The bolt guide includes a projection configured for traveling in the guide channel when moving the bolt body in the receiver so as to ensure that the bolt body is at a predetermined correct angular orientation within the receiver.

Abstract: A bolt used in a self loading firearm employing a bolt carrier which in turn carries the bolt. The bolt includes a cam pin receptacle and a cam pin carried by the bolt. The cam pin includes a body having a received end and an exposed end. The received end is received in the cam pin receptacle with the exposed end extending outwardly from a surface of the bolt. A roller is rotatably coupled to the exposed end and rotatable around an axis of the body.

Abstract: A method of assembling a firearm is provided. The method includes providing a bolt assembly that includes a bolt carrier that includes a cammed slot and a first passage, a bolt member slidably coupled to the bolt carrier and positioned within the first passage, the bolt member includes at least one aperture and a second passage, a piston member slidably coupled to the bolt member and positioned within the second passage, the piston member includes an elongated slot and a third passage, wherein the elongated slot includes a first length, and a cam pin slidably coupled to at least one of the bolt carrier, the bolt member and the piston member, the cam pin includes a fourth passage; and coupling the bolt assembly within a cavity of the firearm such that the bolt assembly is slidably coupled to an upper receiver of the firearm.

Abstract: A bolt used in a self loading firearm employing a bolt carrier which in turn carries the bolt. The bolt includes a cam pin receptacle and a cam pin carried by the bolt. The cam pin includes a body having a received end and an exposed end. The received end is received in the cam pin receptacle with the exposed end extending outwardly from a surface of the bolt. A roller is rotatably coupled to the exposed end and rotatable around an axis of the body.

Abstract: The semiautomatic pistol has a rigidly fixed barrel and sights attached thereto. The body of the pistol receives a breechbolt that moves axially in line with the fixed barrel. Cartridges are transferred from the magazine up to the action in the breechbolt, and spent cartridge cases are ejected out of a side eject port disposed on the pistol. Dismounting of the breechbolt is facilitated by a pivotal dismounting post at the rear of the eject port.

Abstract: New and unique improvements of prior known M4/M16 firearms are disclosed that comprise (A) a bolt which, in addition to all of the normal M4/M16 features is configured or reconfigured to accept a bridged extractor spring which straddles the firing pin and presses against the bottom of the extractor with the bridging wire, and (B) a bridged extractor spring which is a single part, wound with dual spaced helical coils connected with a bridge wire that maintains the spacing at the top of the spring. The bridge wire preferably crosses diagonally between and is tangent to both coils.

Abstract: A breech device for bolt-action firearms includes a breech body reciprocating in the receiver and rotatable into locking position. In its front part, the breech body has locking lugs located in three sectors, the locking lugs in at least two sectors being formed in a breech device equipped with a magazine loaded in parallel so that there are four guide surfaces to limit rotation between the receiver and the breech body, and the breech body has a recessed locking surface for the cartridge at its end. The locking surface of the cartridge has been extended downwardly to form a glide surface passing between the locking lugs so that the rear surface of the cartridge case slides on the glide surface and the locking surface into locking position as the cartridge is ejected from the magazine into the cartridge housing.

Abstract: New and improved bolt assemblies for M4/M16 firearms capable of firing a remarkably greater number of rounds than previously available M4/M16 firearms are, disclosed that have right and left compression springs that are parallel to each other, straddle the firing pin bore and are retained in partial bores that have proximal and distal ramps descending from their open ends. Additionally, these bolt assemblies advantageously (A) have the extractor pivot pin receiving lug is positioned at the longitudinal center of the mass of the extractor, (B) walls of bolt lugs on the firearm bolt are angled tangent to full radius fillets joining adjacent bolt lugs, (C) the extractor contains a ceramic ball and a captive rubber spring to bias such ball against the extractor pivot pin to retain it in the receiving lug and (D) lugs on the barrel extension are angled tangent to substantial radius fillets joining them.

Abstract: An elastic sleeve having a longitudinal slit is positioned between a bolt head and bolt carrier. The sleeve is inserted into an annular space in the bolt carrier when the sleeve is radially compressed allowing relative movement between the bolt head and bolt carrier. The sleeve is supported between the bolt head and an end surface of the bolt carrier when the sleeve is expanded preventing relative movement between the bolt head and the bolt carrier. The periphery of the uncompressed elastic sleeve contacts the bolt carrier or bolt head to thereby effectively damp the elastic sleeve.

Abstract: The bolt assembly includes a bolt head having a locked position and an unlocked position. The bolt head also has a periphery and an even number of arrangement sites located on the periphery. The bolt assembly further includes a plurality of locking projections positioned at a subset of the arrangement sites on the periphery of the bolt head. It also includes a cartridge extractor disposed at one of the arrangement sites which is not part of the subset and which is located horizontally adjacent the central longitudinal axis of the barrel when the bolt head is in the unlocked position.

Abstract: A shotgun comprises a receiver made from a first material; barrel having a portion extending into the receiver and made from a second material; a collar nut securing the barrel to the receiver; a bolt assembly disposed within the receiver and including a locking block configured to project into the barrel portion and lock the bolt assembly to the barrel prior to firing, the bolt assembly including a firing pin; and a trigger mechanism including a hammer for striking the firing pin.

Abstract: Straight-pull breechblock (20) with rotating-boss locking mechanism for repeating weapons, having a breechblock head (27) which is guided in a longitudinally and rotationally movable manner in a breechblock housing (22) and has locking bosses (42, 43), and having a breechblock sleeve (24) which carries a bolt handle (28) and in which is mounted a firing pin (23) which is acted upon by a firing spring (53), for the movement of the breechblock head (27) in the longitudinal direction, while the rotational movement thereof is forced by way of the pretension of the firing spring (53) which acts on the firing pin (23), wherein by way of a forcibly controlled spring-mounted stopping lever (58) associated with the breechblock sleeve (24), relative movements between the breechblock head (27) and the breechblock sleeve (24) can be prevented until the breechblock head (27) has gone into the region of the locking chamber (44) of the breechblock housing (22).

Abstract: A locking mechanism for use in a wide variety of firearms to assist in securing the firearm from unauthorized use, the locking mechanism being rotatable between an unlocked position where it allows movement of the firing pin and a locked position where it prevents movement of the firing pin.

Abstract: An improved bolt carrier for a firearm is provided that improves the overall reliability and performance of the firearm bolt assembly. The bolt carrier includes a bolt with a body having a number of lugs extending therefrom. The lugs are integrally connected to the body and define a fillet extending between a sidewall of the lug and the outer surface of the body of the bolt. The bolt also includes an extractor pivotably engaged in a recess formed in the bolt. The extractor has a pair of flanges configured to engage a pair of springs disposed on either side of a firing pin bore extending through the bolt.

Abstract: A gas-operated pistol which comprises a frame having a handgrip and adapted to receive a magazine. A slide is mounted for alternating longitudinal movement along the frame. A barrel is provided which is able to pivot at its muzzle end and rotate upwards from a locking engagement via locking means with the frame to allow a cartridge to be removed. An actuating means rotates the barrel upwards after the high pressure period has passed. A cylinder is located above the barrel and communicates with the barrel bore via a passage. The action of propellant gases in the cylinder on the piston urges the slide rearwards. This arrangement reduces the effect of felt recoil on the firer when using very powerful cartridges.

Abstract: Reliability of a multi-lug breech bolt is improved by modifying the bearing relationship between the bolt lugs and the matching lugs within a gun receiver. This procedure is applied to a gun that has a receiver housing a breech bolt and an extractor. The extractor is coupled to the breech bolt and configured to move relative thereto. The bolt for this gun has at least five radially extending bolt lugs configured for bearing contact with the receiver when positioned for firing. The bolt lugs include a first, second, and third bolt lug with the first and second bolt lugs being adjacent and defining a gap configured to receive the extractor therebetween. The third bolt lug extends from the bolt opposite the gap. Stress imparted to the first and second bolt lugs from firing the gun is reduced by altering the gun to prevent formation of a bearing relationship between the third bolt lug and the receiver when the bolt lugs are positioned for firing. The gun is reassembled as part of the procedure.

Abstract: The invention concerns a firearm for receiving and firing a projectile. The firearm includes an integral casing having a barrel and a breech block receiving area to the rear of the barrel. A breech block is guided through the breech block receiving area by separated guide pins which project from the breech block into respective longitudinal track sections in the barrel. The guide pins are axially separated at opposite ends of the breech block and are circumferentially separated. The longitudinal track sections meet circumferential track sections. The guide pins in the circumferential track sections permit the breech block to be rotated. The breech block has a forward closed barrel position and a rearward open loading position. A breech mount around the breech block has a cam slot that extends longitudinally and into which a cam follower pin from the breech block projects. The breech mount is drawn forward by a spring and driven rearwardly by the gas pressure from detonation of a projectile leaving the barrel.

Abstract: A modified M16 pistol capable of firing rifle cartridges therein in automatic or semi-automatic mode, which pistol is based upon modified M16 upper and lower assemblies, with a pistol barrel, an M16 gas actuation system, and a spring-biased buffer system mounted on top of the M16 upper receiver assembly.

Abstract: An M16 type rifle is disclosed having a gas piston assembly with a relatively large piston area and sufficient stroke to actuate the M16 bolt carrier assembly in order to allow the M16 rifle to be chambered for short low-pressure pistol cartridges such as the 45 ACP, 10 mm, and 40 S&W. The gas piston assembly provides relatively constant contact between the piston rod and the gas carrier key of the conventional M16 bolt carrier assembly.