Based on the analysis of scientific points of view and practice of investigating the illegal manufacture, processing, or repair of firearms or falsification, the illegal removal or change of its marking, or the illegal manufacture of ammunition, explosives, or explosive devices, typical types of forensic examinations carried out in such criminal proceedings are identified. The values of the selected forensic examinations for criminal procedural proof have been established, typical errors in their appointment and conduct have been identified, ways to prevent and solve them have been proposed.
The effectiveness of the expert opinion and its use by the investigator depends not only on the legality and validity of his preparation by the expert, the solution of all the necessary questions that were put before him/her but also on the admissibility and belonging of obtaining evidence during investigative (search) actions, based on which expertise is being conducted. Prevention and elimination of these negative factors will contribute to the prevention of expert errors, will contribute to the effectiveness of the investigation of crimes in this category.
Key words: forensics examination, investigation, firearms, ballistics, explosive