Abstract: A firearm system including a shell having an electrically conductive contact disposed axially of a shell insulator having a rearwardly facing curved surface, the shell insulator being disposed centrally of a metal jacket portion of the shell, the first end of the shell contact being exposed at the rearwardly facing surface of the shell insulator and a second end of the shell contact extending inwardly of the shell and in contact with a reservoir of powder; and a firearm comprising a housing having a chamber for receiving the shell, an electrical circuit mounted in the housing and including a contact mounted in a chamber insulator having a forwardly facing surface complementary to the shell insulator, the chamber insulator being disposed in the chamber and adapted for engagement with the shell insulator, to place the shell contact in engagement with the chamber contact, a power source disposed in the circuit, and a trigger mounted on the housing and movable by an operator to close the circuit whereby to place