Gunshot residue (GSR), also known as
cartridge discharge residue (CDR), "gunfire residue"(GFR), or
firearm discharge residue (FDR), is residue deposited on the hands and clothes of someone who discharges a
firearm. It is principally composed of burnt and unburnt particles from the
explosive primer, the
propellant—and possibly fragments of the
bullet,
cartridge case, and the
firearm.