I have a question regarding passive RFID devices, in the context of weapons design....could a passive RFID chip be mounted to a magazine follower (in layman's terms, a magazine follower is a device in a firearm's magazine which pushes the cartridges into the chamber of the firearm, usually constructed of stamped steel or other alloy and installed above the magazine spring) and be used by a RFID reader located in the weapon to identify what type of magazine had just been inserted (a 20, 30, 40 round magazine, etc.) plus how many rounds were actually in the magazine by somehow measuring the distance from the RFID chip to the RFID reader. That data could be relayed to a heads-up or ocular display. For example, a soldier with an empty weapon, no magazine inserted, finds a partially full magazine and inserts it into his own empty weapon. The RFID reader reads the passive RFID chip and designates this magazine as a 40-round magazine, but by measuring distance from the reader to the chip, determines that there are only 13 rounds remaining in this particular magazine. This data could be relayed to a display as "13/40" or something easily understood. How complex and large would such a system have to be?
