Disclosed is tagged ammunition, methods for making it, using it and detecting it to reduce gun violence. When implemented together with a smart phone coupled readers, standalone readers, or at a security center, software is included to allow integration of signals detected by multiple readers in the vicinity to map detectable ammunition detected by readers designed to detect tagged ammunition as a proxy for loaded firearms. This makes possible securing an area of interest, when combined with placing of at least one networkable reader in the vicinity of the area of interest; and connecting the one or more readers to a monitoring center. Such monitoring centers may be associated with schools, shopping malls, streets, public meetings, public events, housing complexes, an area being swept for loaded guns, an area being monitored for gang activity, or even a residence.