Abstract: A machine pistol with means for retarding blowback of the slide assembly. The device has both right hand and left hand stocks to enable the weapon to be fired from a comfortable visual sighting position at eye level with the wrist axes perpendicular to one another. The slide assembly includes a bolt that carries the firing pin, extractor and ejector and that reciprocates relative to the receiver and barrel, and a tubular cylindrical muzzle sleeve removably connected to the forward end of the bolt and that fits coaxially around the barrel. A coaxial helical spring fits between the barrel and muzzle sleeve to urge the muzzle sleeve (and bolt) to the forward firing position wherein the forward end of the muzzle sleeve extends outwardly beyond the end of the barrel.

Abstract: A firearm in the form of a submachine gun which can fire in either a semiautomatic or full automatic mode. The firearm is provided with a front sear, a front trigger and a rear sear/trigger in a construction which allows the operator to instantly change between the semi and fully automatic mode without a selector switch, even while firing. Other features include capability for ambidextrous operation, the use of two magazines each located in a separate handgrip and an improved muzzle brake configuration. In addition, an improved ejector and magazine catch assembly are provided. The firearm of the present invention employs fewer moving parts so as to require no pins or screws for the trigger, sear, bolt guide or bolt stop.

Abstract: Disclosed is a slide stop assembly for a handgun including a slide stop pivotal from an inoperative position into a position engaging the slide when the latter is in a recoiled position. A generally flat, shallow V-shaped, side plate is secured along one side of the frame against rotation or rocking movement. The securement is effected by engagement of the side plate at spaced points therealong with the respective hammer and sear pins of the handgun. One leg of the side plate extends forwardly and terminates in a tab. A spring biased plunger on the slide stop engages the tab to preclude inadvertent pivoting of the slide stop from its inoperative detented position into its slide stop position.

Abstract: A gun conversion assembly for application to the receiver of an automatic pistol having a handle containing a recess into which a magazine holding a series of rounds of ammunition is insertible, the conversion assembly including a barrel to be secured to the receiver, and a connector structure having a portion which is adapted to be located within the magazine recess in the receiver handle and which acts to secure the barrel rigidly to the receiver. The connector structure may extend downwardly through the recess to the bottom of the receiver handle and have elements at the lower end of the handle tightenable to progressively pull the receiver downwardly into tightly contacting engagement with the upper end of the receiver.

Abstract: A shock-absorbing recoil mechanism for a semiautomatic firearm includes a pair of rigid plates positioned on opposite sides of a resilient sheet of energy-dissipating material. The plates and sheet are positioned in the U-shaped cavity of the firearm frame against reduced diameter shoulders formed toward the rear end thereof. The slide, when moving to its recoil position, thus contacts the forward plate instead of the shoulder in order to reduce the peak value of the recoil force applied to the frame by the slide. The shock-absorbing assembly may be combined with the recoil spring by utilizing a spring guide rod which projects through the plates and resilient material. The recoil spring surrounds the guide rod and projects forwardly against a cap mounted in the forward end of the slide.

Abstract: A self-loading firearm or pistol has an operating lever which can be actuated by the thumb of the shooting hand in order to release the hammer from its cocked position as well as to release the breech mechanism retaining the block in an open position. The operating lever comprises two operating lever members, each of which is disposed on one side of the firearm and both lever members are rigidly and firmly interconnected such that one of the operating lever members can be actuated by the thumb of the shooter's hand whether it is the right hand or the left hand.

Abstract: A linear bearing insert for the slide-receiver ways of a firearm wherein the slide is reciprocably attached to the receiver by a groove and tongue structure. The insert is in the form of a rod, preferably cylindrical, which is disposed in a groove, preferably the receiver groove, and which has a portion of its peripheral surface in sliding engagement with a partially cylindrical groove formed in the side of a corresponding tongue, such that the bearing surfaces in engagement are cylindrical rather than planar. After wear has taken place, causing objectionable play, the insert may be replaced by a larger size insert such as to compensate for wear and eliminate the play.

Abstract: A device for loading and firing semi-automatic arms, particularly pistols, and comprising a plurality of follower lugs or pins carried in the slide, and a corresponding plurality of inclined grooves carried in the yoke and engaged by the lugs or pins so as to disengage the yoke and the bolt from the barrel when the slide is retracted under the pressure of the gases from a fired cartridge.

Abstract: A slide decelerator assembly for a firearm (1), having a slide (2) which moves rearwards when the firearm (1) is fired is described comprising means (12, 13) for compressing air in response to said rear movement of said slide 2for retarding said rear slide movement.

Abstract: A semiautomatic hand gun having a unique take down assembly which allows the slide assembly to be detachably secured to the frame. This take down mechanism comprises a pin which may be removed without tools and which is captured in a disengaged position to prevent loss.

Abstract: A sight base bridge for an automatic pistol having relative movement between its slide and barrel, said bridge permitting the mounting of sights directly to the pistol barrel, thus eliminating inaccuracy caused by tolerances between the barrel and slide formerly having the sights thereon. A similar mounting system can be used for attachment of silencers and compensators.

Abstract: Disclosed is a semi-automatic firearm which has a configuration generally similar to a known form of submachine gun insofar as it comprises an elongate receiver, a pistol grip extending downwardly from the receiver and forming a housing for a cartridge magazine and a trigger mechanism and sear located forwardly of the pistol grip. The firearm operates on the blowback principle with closed breech type operation and employs a slidable bolt and separate slidable firing pin striker mechanism within the receiver, with the bolt being freely slidable and the sear operating on the striker mechanism. The trigger mechanism only has a semi-automatic and a safety setting and the bolt face has a feed lip of a design which causes the firearm intentionally to jam under certain abnormal operating conditions.

Abstract: A ball bearing hammer actuator comprises a hammer lever which is connected at the one end to the hammer and which is connected at the other end to a shoe which is slidable in relation to guide surface having a U-shaped cross section. The guide surface is provided for by a portion of the frame which has a generally U-shaped cross section. The shoe of the ball bearing hammer actuator includes a body having a generally rectangular shape which is designed to fit within the U-shaped guide. The shoe fits within the guide with a small clearance, the clearance allowing for use of ball bearings. Two edges of the body of the shoes include elongated recesses. The recesses receive a plurality of bearing balls therein. The bearing balls protrude from the bottom of the shoe and the sides of the shoe. The bearing balls are in contact with the walls and the floor of the U-shaped guide. A spring mechanism urges the shoe upwardly.

Abstract: An arrangement in firearms having a barrel and a bolt.The bolt is provided with means mounting the bolt for axial displacement and rotation on the outside of the barrel. A carrier displaceably mounted on the outside of the barrel is operatively connected to the bolt to axially displace the bolt to and from a firing position and to rotate the bolt in said position to engage and disengage the bolt at locking means on the outside of the barrel by axial displacement of the carrier.

Abstract: A generally tubular member is provided at one end thereof with securing means for detachably securing such member as to a pistol type firearm and to be generally aligned with the bore of such firearm, forwardly thereof; the tubular member has aperture or porting means formed in a selected portion of the wall forming the tubular member whereby gases, generated during the ignition of a related bullet assembly, may escape in a generally upwardly direction thereby creating generally downwardly directed reaction forces assisting in maintaining the fired firearm stable and at least significantly eliminate the usually experienced sudden upward jump of such fired firearm.

Abstract: The invention provides a barrel locking device for automatic pistols, and a sub-caliber conversion therefor. The essential elements of the locking device are the barrel, the aligning cheeks at the rear end of the barrel, the barrel extension member, a link pivotally connected to such barrel extension member and having a hole therein, a slide-stop having a pivot pin for engagement in a transverse through hole in the piston receiver and in the hole in the link, and a barrel locking screw which engages in a threaded hole in the front face of the extension member. Upon tightening of the barrel locking screw the link is rotated forwardly and pulls the barrel and slide into intimate contact with the receiver by engagement of the barrel cheeks with the upper surface of the receiver.

Abstract: A barrel is fixedly inserted in and protrudes from a grip and comprises a barrel chamber. A piston is provided on the outside of said barrel and rigid therewith. A breechblock comprises a cylinder surrounding said barrel and piston before said grip and defining with said barrel an annular chamber, which is sealed against said barrel. Said breechblock is movable along said barrel to and from a forward position. A counterrecoil spring urges said breechblock to said forward position. A piston is disposed in said annular chamber and rigid with said barrel and arranged to be disposed at the rear end of said annular chamber when said breechblock is in said forward position. Transverse bore means are formed in said barrel and communicate with the interior of said barrel adjacent to said barrel chamber. Longitudinal passage means are provided, which are laterally enclosed and connect said transverse bore means to said annular chamber.