Pervasiveness of inorganic gunshot residue (IGSR) in handguns after cleaning and conditioning procedures.

Memory effect in firearms that is, the possibility for a weapon to release inorganic particles whose elemental composition depends on its entire shooting history, is responsible for most of the interpretation difficulties encountered in forensic gunshot residue analysis. The presence of residues chemically inconsistent with the last discharged round, the creation of particles having unusual elemental profiles, and the dependence of residue population composition on the collection point are all manifestations of memory effect. The experimental results reported in this paper highlight the ineffectiveness of a wide number of gun cleaning procedures in reducing memory effect.

A simple voltammetric method to evaluate the firing distance through determination of nitrocellulose.

Nitrocellulose (NC) is the main component of propellants for small firearm ammunitions. Even though NC particles are ejected from gun barrels together with bullets and they are often recovered on close-to-muzzle targets, quantitative analysis of nitrocellulose for forensic purposes has been neglected so far. Moreover, although the presence of the nitroester groups makes nitrocellulose electroactive, its electrochemical determination has been poorly considered in literature.