Abstract: A muzzle-mounted chronograph for measuring velocities of projectiles launched from firearms. The chronograph includes a sensor module and a controller. The sensor module includes a first and second coils and a device for applying a stable magnetic field to the first and second coils. The controller determines a velocity of a projectile passing by the first and second coils based on detected variations in magnetic fields at the first and second coils.

Abstract: This disclosure relates to a system and method for storage of a modular cartridge within a cavity formed in a portion of a firearm, wherein the cavity is not the magazine well of the firearm. The disclosure provides for a system for disengagebly retaining such modular cartridges, as well as multiple embodiments of cartridges which may be retained therein. Such embodiments of modular cartridges include: a miniature magazine (mini-mag) which may be used to store ammunition, and which may be operable as a magazine for the firearm; a dry box which may be used to store materials in a manner in which they are protected from the ambient environment; a monopod which may be used to help support a firearm; a flashlight; and a battery charger, which may provide for a usb output.

Abstract: This disclosure relates to a system and method for storage of a modular cartridge within a cavity formed in a portion of a firearm, wherein the cavity is not the magazine well of the firearm. The disclosure provides for a system for disengagebly retaining such modular cartridges, as well as multiple embodiments of cartridges which may be retained therein. Such embodiments of modular cartridges include: a miniature magazine (mini-mag) which may be used to store ammunition, and which may be operable as a magazine for the firearm; a dry box which may be used to store materials in a manner in which they are protected from the ambient environment; a monopod which may be used to help support a firearm; a flashlight; and a battery charger, which may provide for a usb output.

Abstract: This disclosure relates to a system and method for storage of a modular cartridge within a cavity formed in a portion of a firearm, wherein the cavity is not the magazine well of the firearm. The disclosure provides for a system for disengagebly retaining such modular cartridges, as well as multiple embodiments of cartridges which may be retained therein. Such embodiments of modular cartridges include: a miniature magazine (mini-mag) which may be used to store ammunition, and which may be operable as a magazine for the firearm; a dry box which may be used to store materials in a manner in which they are protected from the ambient environment; a monopod which may be used to help support a firearm; a flashlight; and a battery charger, which may provide for a usb output.

Abstract: A muzzle-mounted chronograph for measuring velocities of projectiles launched from firearms. The chronograph includes a sensor module and a controller. The sensor module includes a first and second coils and a device for applying a stable magnetic field to the first and second coils. The controller determines a velocity of a projectile passing by the first and second coils based on detected variations in magnetic fields at the first and second coils.

Abstract: This disclosure relates to a system and method for storage of a modular cartridge within a cavity formed in a portion of a firearm, wherein the cavity is not the magazine well of the firearm. The disclosure provides for a system for disengagebly retaining such modular cartridges, as well as multiple embodiments of cartridges which may be retained therein. Such embodiments of modular cartridges include: a miniature magazine (mini-mag) which may be used to store ammunition, and which may be operable as a magazine for the firearm; a dry box which may be used to store materials in a manner in which they are protected from the ambient environment; a monopod which may be used to help support a firearm; a flashlight; and a battery charger, which may provide for a usb output.

Abstract: A multi-reel, line-handling apparatus can include a housing, a shaft located within the housing, the shaft defining a shaft axis, a first reel located within the housing, the first reel rotatably mounted to the shaft about a first reel axis angled with respect to the shaft axis, and a second reel located within the housing, the second reel rotatably mounted to the shaft about a second reel axis angled with respect to the shaft axis. The first reel and the second reel can be rotatable with respect to the housing about the shaft axis.

Abstract: An apparatus for preventing entanglement of lines fed from separate reels has at least two reels mounted on separate axles. A separate line is wound around each reel. Each axle is mounted on one of at least two rotatable split shaft members. Each split shaft member is connected to one of at least two non-rotating controls by means of one of at least two non-rotating brake rods, arranged such that operating one or another of said controls results in one or another of said reels being made to contact a fixed portion of the apparatus and brought to a halt or, if already halted, released and positioned so as to permit the line wound thereon to resume being fed out.

Abstract: A multi-reel, line-handling apparatus can include a housing, a shaft located within the housing, the shaft defining a shaft axis, a first reel located within the housing, the first reel rotatably mounted to the shaft about a first reel axis angled with respect to the shaft axis, and a second reel located within the housing, the second reel rotatably mounted to the shaft about a second reel axis angled with respect to the shaft axis. The first reel and the second reel can be rotatable with respect to the housing about the shaft axis.

Abstract: An apparatus for preventing entanglement of lines fed from separate reels has at least two reels mounted on separate axles. A separate line is wound around each reel. Each axle is mounted on one of at least two rotatable split shaft members. Each split shaft member is connected to one of at least two non-rotating controls by means of one of at least two non-rotating brake rods, arranged such that operating one or another of said controls results in one or another of said reels being made to contact a fixed portion of the apparatus and brought to a halt or, if already halted, released and positioned so as to permit the line wound thereon to resume being fed out.