In recent years, the use of illegally produced firearms has increased exponentially worldwide. These are often cheap, nonstandard firearms that defy known classification and identification criteria. The use of unusual firearms in crimes has frequently led to unpredictable and misleading reconstruction of shooting incidents. In this book, internationally known forensic firearm expert, J.K. Sinha, presents a detailed forensic study of unusual firearms, with the goal of helping crime-scene investigators to minimize erroneous conclusions in cases where these types of firearms are used. Based on his extensive experimentation with more than 1,000 nonstandard firearms, the author identifies new class characteristic parameters needed to establish linkage of projectiles with irregular rifled and smoothbore barrels. The book begins with an introduction to unusual firearms and proceeds to discuss forensic investigation of fired bullets, medico-legal evidence, barrel marks on fired shots, and investigation of fired cartridges and shot charge. Chapters also cover topics such as timing of firing, unusual rifling marks, shooter identification, and unusual bullet hole evaluations. Providing concise yet complete techniques for making forensic analyses and conclusions, this is the first book of its kind to critically examine the use of unusual, nonstandard firearms in perpetrating crimes. It is intended for professionals and academicians working in the field: forensic firearm experts and consultants, forensic medicine professionals and medico-legal experts, prosecution and defense attorneys, enforcement agencies and judiciary, university students and researchers studying forensic science, forensic medicine, criminology and law.