Abstract: A round counter for a firearm is provided that includes a display that provides the user with information regarding the number of rounds remaining in the magazine of the firearm. The magazine includes a round follower and a wiper extending from the follower. The wiper contacts a variable resistance sensor, such as a linear potentiometer, that is attached to a sidewall of the magazine. As the round follower and wiper move up and down within the magazine, the wiper contacts the sensor at different positions. The position of the wiper relative to the sensor corresponds to a specific linear distance indicative of the number of rounds remaining in the magazine. Information regarding this position, and consequently the number of remaining rounds is transmitted to the display.

Abstract: A round counter for a firearm is provided that includes a display that provides the user with information regarding the number of rounds remaining in the magazine of the firearm. The magazine includes a round follower and a wiper extending from the follower. The wiper contacts a variable resistance sensor, such as a linear potentiometer, that is attached to a sidewall of the magazine. As the round follower and wiper move up and down within the magazine, the wiper contacts the sensor at different positions. The position of the wiper relative to the sensor corresponds to a specific linear distance indicative of the number of rounds remaining in the magazine. Information regarding this position, and consequently the number of remaining rounds is transmitted to the display.