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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Composition of primer is
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The correct answer is  The primers are composed of lead styphnate, barium nitrate and antimony sulphide. Most centrefire primers are composed of all the three compounds. The detection of these compounds constitutes the basis for the tests to determine whether an individual has fired a firearm. In case of rimfire ammunition, the primer composition is spun into the rim of the caridge case with the propellant in intimate contact with this composition. On firing, the firing pin strikes the rim of the caridge case, compressing the primer composition and initiating its detonation Ref : Krishnan vij Textbook of Forensic medicine and Toxicology 5th edtion ; pg no - 237