Arrangement for determining the presence of a cartridge in a cartridge chamber of a weapon

An arrangement for determining the presence or absence of a cartridge casing in a cartridge chamber of a weapon, in particular a machine cannon, comprising in combination,

• a housing having a recess,
• a lever pivotally mounted in said recess of said housing about an axis which is parallel to the gun barrel axis of the weapon, said lever having a first feeler arm which is adapted to extend into the cartridge chamber to thereby detect the presence of a cartridge casing in said cartridge chamber;
• and including a breech block operatively slidably mounted in said weapon, said breech block having a pocket, said lever having a second feeler arm, sensor switch means operatively mounted in said housing and adapted to coact with said second feeler arm, biasing means operatively mounted in said housing and biasing said second feeler arm away from said sensor switch means, whereby when a cartridge casing is seated in said cartridge chamber and the breech block is in the forwardmost operative position the edge of the bottom of the cartridge casing projects past the bottom of said pocket of said breech block thereby contacting said first feeler arm and pivotally biasing said second feeler arm against said sensor switch means against the action of said biasing means.