Ballistics, Law Assistance, and Safety Technology Act (BLAST Act) - Amends the Brady Handgun Violence Prevention Act to require a licensed manufacturer or importer of firearms to: (1) test fire manufactured or imported firearms as specified by the Secretary of the Treasury; (2) prepare ballistics images of the fired bullet and cartridge casings; (3) make the records available to the Secretary for entry into a computerized database; and (4) store the fired bullet and cartridge casings.

Directs the Attorney General and the Secretary to assist firearm manufacturers and importers in complying with these requirements through: (1) the acquisition, disposition, and upgrades of ballistics equipment and bullet and cartridge casing recovery equipment; (2) the hiring or designation of personnel necessary to develop and maintain a ballistics database; (3) providing education about the role of ballistics; and (4) providing for the coordination among law enforcement, regulatory agencies, and the firearm industry to curb firearm-related crime and illegal firearm trafficking.

Requires the Attorney General and the Secretary to: (1) establish a computer system through which State and local law enforcement agencies can promptly access ballistics records; (2) encourage training for ballistics examiners; (3) report to Congress on the impact of this Act on criminal investigations, arrests, indictments, and prosecutions; and (4) conduct mandatory ballistics testing of all firearms obtained by or in the possession of their respective agencies.

Prohibits the use of ballistics information of individual guns for prosecutorial purposes unless officials have a reasonable belief that a crime has been committed and that ballistics information would assist in the investigation.