An explosive device contains a water-reactive material that ignites upon exposure to water. The water-reactive material ignites a water-activated fuse that has a predetermined burn rate and length. The predetermined burn rate and length allows the device to sink to a desired depth before exploding. Hence, the device explodes after a desired period of time and/or at a desired depth. Defense against underwater swimmers is an advantageous feature of embodiments of the disclosure. The device can use a forty millimeter (40 mm) form factor, which permits launch of the device from convention grenade launchers.

An explosive device contains a water-reactive material that ignites upon exposure to water. The water-reactive material ignites a water-activated fuse that has a predetermined burn rate and length. The predetermined burn rate and length allows the device to sink to a desired depth before exploding. Hence, the device explodes after a desired period of time and/or at a desired depth. Defense against underwater swimmers is an advantageous feature of embodiments of the disclosure. The device can use a forty millimeter (40 mm) form factor, which permits launch of the device from convention grenade launchers.

According to a first aspect of the invention, there is provided a programmable system for a munition, comprising: an electroacoustic transducer, arranged to receive an acoustic signal comprising data, and convert that signal into an electrical signal comprising data; a processor, arranged to receive and process the electrical signal comprising data, and to use that data in programming of the programmable system.

Cocking tab inserts and breechblock slides and firearms including the same are disclosed. An example apparatus includes a breechblock slide; a cocking tab insert removably coupled to the breechblock slide; and a sight removably coupled to the breechblock slide and overlaying the cocking tab insert to substantially prevent the cocking tab insert from being inadvertently removed from the breechblock slide.

Cocking tab inserts and breechblock slides and firearms including the same are disclosed. An example apparatus includes a breechblock slide; a cocking tab insert removably coupled to the breechblock slide; and a sight removably coupled to the breechblock slide and overlaying the cocking tab insert to substantially prevent the cocking tab insert from being inadvertently removed from the breechblock slide.

According to a first aspect of the invention, there is provided an object for moving through a fluid, the object comprising: an outer housing, arranged to be exposed to a hydrostatic pressure exerted by the fluid; a strain gauge, arranged to obtain an indication of the hydrostatic pressure, wherein a first part of the strain gauge is arranged to be in contact with the outer housing, such that the strain gauge is arranged to obtain an indication of the hydrostatic pressure by obtaining an indication of the strain on the housing.

According to an aspect of the invention, there is provided a fuze arming system for a submunition, comprising: a first stage, arranged to detect launch of the submunition and its associated carrier; a second stage, arranged to detect expulsion of the submunition from the carrier, and to at least partially arm a submunition fuze based on such detection; wherein the second stage is unable to at least partially arm the submunition fuze without the first stage detecting launch of the submunition and its associated carrier.

According to a first aspect of the present invention, there is provided a munition assembly, arranged to be launched from a gun, the assembly comprising: a carrier for a submunition, the carrier comprising a cavity in which the submunition is located; and a submunition, carried by the carrier in the cavity, the submunition arranged to be controllably expelled from the carrier; the submunition comprising: a submunition explosive charge; and a submunition fuze, wherein: the munition assembly is adapted to be launched, into the air, from a gun barrel, where the submunition is then arranged to be controllably expelled from the carrier and enter a body of water; and the submunition fuze is adapted to trigger the submunition explosive charge under water.

According to an aspect of the invention, there is provided a method of triggering an explosive charge of each of a plurality of munitions, the method comprising: launching a first munition, into the air, from a first gun barrel, and into water to engage with a target location, the first munition comprising a first explosive charge and a first fuze system, adapted to trigger the first explosive charge in the water, launching a second munition, into the air, from a second gun barrel, and into water to engage with the target location, the second munition comprising an second explosive charge and a second fuze system, adapted to trigger the second explosive charge in the water, the method comprising co-ordinating the timing of the triggering of the first explosive charge and the second explosive charge to establish a co-ordinated explosive event at the target location.

According to an aspect of the invention, there is provided a fuze arming system for a submunition, comprising: a first stage, arranged to detect launch of the submunition and its associated carrier; a second stage, arranged to detect expulsion of the submunition from the carrier, and to at least partially arm a submunition fuze based on such detection; wherein the second stage is unable to at least partially arm the submunition fuze without the first stage detecting launch of the submunition and its associated carrier.