A handgun includes a barrel which extends in a longitudinal direction, and a breechblock with a breechblock insert. The breechblock insert can be brought into a first state and into a second state where, in the longitudinal direction of the barrel, the second state has a play which is greater than a play in the first state.

A revolver has a detent mechanism providing positive mechanical engagement between the cylinder yoke and the frame. A housing mounted on the frame has a spring biased plunger that transversely engages a pin. The pin projects from the housing and engages a recess on the yoke when the revolver cylinder is closed. The pin is biased into engagement with the recess by the plunger to maintain the revolver closed and the chambers of the cylinder in precise alignment with the barrel during firing. Manual force applied to the cylinder can overcome the biasing force and permit the revolver to be opened and closed.

A revolver has a detent mechanism providing positive mechanical engagement between the cylinder yoke and the frame. A housing mounted on the frame has a spring biased plunger that transversely engages a pin. The pin projects from the housing and engages a recess on the yoke when the revolver cylinder is closed. The pin is biased into engagement with the recess by the plunger to maintain the revolver closed and the chambers of the cylinder in precise alignment with the barrel during firing. Manual force applied to the cylinder can overcome the biasing force and permit the revolver to be opened and closed.

A firearm lock mechanism includes a trigger, a hammer, a stirrup connected to the hammer at a stirrup connection point, and a spring operably connected to the stirrup at a spring connection point. Progressive pivoting of the trigger drives corresponding progressive pivoting of the hammer. The stirrup connection point is disposed forward of the hammer pivot point. One of the spring connection point, hammer pivot point, and stirrup connection point is offset relative to and laterally spaced between the others of the points to be a vertex of an intermediate angle cooperatively defined by the points. The angle increases in magnitude as the trigger drives pivoting of the hammer. A toggle line is defined between the trigger pivot point and the hammer pivot point. The trigger contacts the hammer at a contact point that shifts across the toggle line as the trigger drives pivoting of the hammer.

A revolver has a detent mechanism providing positive mechanical engagement between the cylinder yoke and the frame. A housing mounted on the frame has a spring biased plunger that transversely engages a pin. The pin projects from the housing and engages a recess on the yoke when the revolver cylinder is closed. The pin is biased into engagement with the recess by the plunger to maintain the revolver closed and the chambers of the cylinder in precise alignment with the barrel during firing. Manual force applied to the cylinder can overcome the biasing force and permit the revolver to be opened and closed.

A revolver has a detent mechanism providing positive mechanical engagement between the cylinder yoke and the frame. A housing mounted on the frame has a spring biased plunger that transversely engages a pin. The pin projects from the housing and engages a recess on the yoke when the revolver cylinder is closed. The pin is biased into engagement with the recess by the plunger to maintain the revolver closed and the chambers of the cylinder in precise alignment with the barrel during firing. Manual force applied to the cylinder can overcome the biasing force and permit the revolver to be opened and closed.

A revolver has a shroud for housing a barrel. The shroud has a receptacle formed on an upper surface. The receptacle is aligned with one sight receiving flat on an exterior periphery of the barrel. The flat is located adjacent to the muzzle end of the barrel. A front sight is disposed within the receptacle. A bottom portion of the sight is in registration with the flat so as to prevent rotation of the barrel.

A revolver has a shroud for housing a barrel. The shroud has a receptacle formed on an upper surface. The receptacle is aligned with one sight receiving flat on an exterior periphery of the barrel. The flat is located adjacent to the muzzle end of the barrel. A front sight is disposed within the receptacle. A bottom portion of the sight is in registration with the flat so as to prevent rotation of the barrel.

A cylinder impeller for revolvers, which transmits the trigger pulling movement to a cylinder revolving movement. The impeller includes a cover having inside it a track; a one-piece body having a plate and a slider, said slider being able to slide within and relative to the cover; and a spring arranged between the body slider and the surface of the cover track. Therefore, the cover and the body slide one relative to the other and against the spring action, thus varying the overall length of the impeller and compensating and absorbing possible teeth machining variations of the cylinder extractor.

A cylinder impeller for revolvers, which transmits the trigger pulling movement to a cylinder revolving movement. The impeller includes a cover having inside it a track; a one-piece body having a plate and a slider, said slider being able to slide within and relative to the cover; and a spring arranged between the body slider and the surface of the cover track. Therefore, the cover and the body slide one relative to the other and against the spring action, thus varying the overall length of the impeller and compensating and absorbing possible teeth machining variations of the cylinder extractor.