- 01: Introduction
- 02: History
- 03: Propellants, Firearms, and Ammunition Development
- 04: Modern Firearms Manufacture
- 05: Small Arms Ammunition
- 06: Evidence Handling Procedures
- 07: Equipment and Instrumentation
- 08: Examination of Firearms
- 09: Cartridge and Shotshell Examination
- 10: Characterization and Evaluation of Fired Projectiles
- 11: Bullet Comparison and Identification
- 12: Gunshot Residue and Distance Determination
- 13: Toolmark Identification
- 14: Communicating Results
- Resources
U.S. Department of Justice, Office of Justice ProgramsNational Institute of JusticeThe Research, Development, and Evaluation Agency of the U.S. Department of Justice
Bluing
Home > Modern Firearms Manufacture > Cosmetic Finish > Bluing
Bluing is about 2 millionths of an inch thick.
A knife test easily scratches the surface,
revealing the bare metal beneath.
Bluing is used on steel metal parts to provide a protective coating. This involves an oxidizing chemical process that provides some protection against corrosion. Depending on the specific process, the resulting coating appears as a blue or blue-black color on the metal exterior.
