An apparatus and method for creating the apparatus that holds a bolt open after a last round is fired from a magazine is disclosed. A lower receiver may include at least two cavities. A transfer bar may be configured to fit into a first cavity of the at least two cavities. A hold down may be configured to fit into a second cavity of the at least two cavities. At least a portion of the hold down may be configured to overlap with at least a portion of the transfer bar to hold the transfer bar in place. The transfer bar, when a final round is fired from a magazine in the lower receiver, may be pushed up by a bump in the magazine to transfer upward movement to the transfer bar that catches a bolt and holds the bolt open until activation of a release button.

A gun includes a bolt member that is disposed in a gun body so as to be movable forward and rearward, that moves rearward in response to gas pressure generated by bullet shooting so as to compress a bolt spring, and that moves forward in response to release of the compressed pressure so as to perform a bullet loading operation, and a bolt stop that stops forward movement of the bolt member. The bolt stop (31) has engagement means (36) for engaging with the bolt member which moves forward to reach the engagement means (36) after last bullet shooting, and includes buffer means (40) for buffering an impact force applied to the bolt stop due to the engagement so as to act on the bolt stop.

A gun includes a bolt member that is disposed in a gun body so as to be movable forward and rearward, that moves rearward in response to gas pressure generated by bullet shooting so as to compress a bolt spring, and that moves forward in response to release of the compressed pressure so as to perform a bullet loading operation, and a bolt stop that stops forward movement of the bolt member. The bolt stop (31) has engagement means (36) for engaging with the bolt member which moves forward to reach the engagement means (36) after last bullet shooting, and includes buffer means (40) for buffering an impact force applied to the bolt stop due to the engagement so as to act on the bolt stop.

A replaceable slide notch system for a firearm that includes a replaceable slide notch component dimensioned to fit within a corresponding cavity of a slide. The replaceable slide notch component includes a slide lock notch surface that locks the slide when the firearm's ammunition is exhausted. A second replaceable slide notch component has a second slide lock notch surface that locks the slide at a further rearward position than that of the first slide notch component, thus providing greater chambering/operating force when the slide is released.

A training method and apparatus are disclosed. The training method may include converting a firearm capable of firing live ammunition to a pneumatic training device incapable of firing live ammunition. The training method may further include cycling a pneumatic training device through one or more cycles. Each of the cycles may simulate an actual firing of the firearm. Each of the cycles may also include triggering a trigger assembly of the pneumatic training device, using a charge of a pressurized gas to reset the trigger assembly, and advancing a counter of the pneumatic training device. After a certain number of cycles have been completed, a next cycle may be attempted, but not completed. Accordingly, the training method may enable a user to safely and realistically practice reloading, jam or malfunction clearing, or the like.

The present disclosure relates to an automatic or semiautomatic pistol including a slide and a magazine. The magazine feeder includes an actuator that controls a slide stop. The slide stop, located rearward of the magazine, is designed to switch from a low to a high position. In its high position, the slide stop locks the slide in a rearward position. The pistol also includes a control lever for the slide stop, which is attached at one end to rotate about a pin forward of the magazine. The control lever includes a feeler that is lifted by the control actuator when the magazine is empty, causing the slide stop to switch from its low to high position. The slide stop may have ambidextrous manual releases rigidly connected to each other across the pistol.

The present disclosure relates to an automatic or semiautomatic pistol including a slide and a magazine. The magazine feeder includes an actuator that controls a slide stop. The slide stop, located rearward of the magazine, is designed to switch from a low to a high position. In its high position, the slide stop locks the slide in a rearward position. The pistol also includes a control lever for the slide stop, which is attached at one end to rotate about a pin forward of the magazine. The control lever includes a feeler that is lifted by the control actuator when the magazine is empty, causing the slide stop to switch from its low to high position. The slide stop may have ambidextrous manual releases rigidly connected to each other across the pistol.

A gun includes a bolt member that is disposed in a gun body so as to be movable forward and rearward, that moves rearward in response to gas pressure generated by bullet shooting so as to compress a bolt spring, and that moves forward in response to release of the compressed pressure so as to perform a bullet loading operation, and a bolt stop that stops forward movement of the bolt member. The bolt stop (31) has engagement means (36) for engaging with the bolt member which moves forward to reach the engagement means (36) after last bullet shooting, and includes buffer means (40) for buffering an impact force applied to the bolt stop due to the engagement so as to act on the bolt stop.

A gun includes a bolt member that is disposed in a gun body so as to be movable forward and rearward, that moves rearward in response to gas pressure generated by bullet shooting so as to compress a bolt spring, and that moves forward in response to release of the compressed pressure so as to perform a bullet loading operation, and a bolt stop that stops forward movement of the bolt member. The bolt stop (31) has engagement means (36) for engaging with the bolt member which moves forward to reach the engagement means (36) after last bullet shooting, and includes buffer means (40) for buffering an impact force applied to the bolt stop due to the engagement so as to act on the bolt stop.

Methods, devices, and systems include a composition for a metal alloy comprising tungsten (W), tantalum (Ta), and boron (B) crystallized in an orthorhombic phase, wherein the composition satisfies the formula W.sub.1-xT.sub.axB wherein x has a value within the range 0.01 to 0.99, inclusively.