05142805 is referenced by 42 patents and cites 5 patents.

A cartridge monitoring and display system for an automatic or semiautomatic firearm. A programmed microcontroller receives input signals from each of a slide switch and a magazine switch, which switches generate respective signals upon actuation of the firearm slide and upon insertion or withdrawal of a cartridge magazine. The microcontroller calculates the number of rounds remaining in the firearm and displays the number on an LCD display. A visible and audible warning is given when the cartridge count drops below a predetermined minimum level. The entire system is incorporated in a mounting strap which may be inserted between the frame and hand grip of a conventional semiautomatic pistol.

Title
Cartridge monitoring and display system for a firearm
Application Number
458582
Publication Number
5142805
Application Date
March 4, 1991
Publication Date
September 1, 1992
Inventor
Michael A Wolf
3195 Arizona, Los Alamos, 87544
NM, US
John N Horne
2145 B 34th, Los Alamos, 87544
NM, US
Agent
William A Eklund
IPC
F41A 9/62
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