Firearms Section Firearms Section SOP Comparative & Analytical Division Firearms Firearms Section SOP Comparative & Analytical Division Table of Contents 1. Introduction .................................................................................................................................4 2. Functions And Responsibilities .....................................................................................................5 3. Utilization of a Second Examiner ..................................................................................................6 4. Instruments, Calibration, And Reagents .......................................................................................7 4.1. General Requirements for Analytical Instrumentation:....................................................................7 4.2. Out of Service Instruments or Balances:...........................................................................................7 4.3. Comparison Microscopes:.................................................................................................................7 4.4. Calipers/Micrometers: ......................................................................................................................8 4.5. Balances: ...........................................................................................................................................9 4.6. Steel Rules:........................................................................................................................................9 4.7. Digital Force Gauges: ........................................................................................................................9 4.8. Secondary Weights: ........................................................................................................................10 4.9. Reference Standards: .....................................................................................................................11 4.10. NIBIN Section: ...............................................................................................................................11 4.11. Reagents:.......................................................................................................................................11 4.12. Infrequently Performed Analyses: ................................................................................................12 5. Reporting Guidelines..................................................................................................................13 5.1. General Report Format ...................................................................................................................13 5.2. Specific Wording for Results and Interpretations Section: .............................................................17 5.3. Specific Wording for the NIBIN Details Section:..............................................................................26 5.4. Reporting Format and Guidelines for Firearms Submitted for Unloading Only:.............................28 5.5. Reporting Guidelines for Evidence Processed for NIBIN Only Entry (NIBIN Notification):..............29 5.6. High Confidence Correlation Notification (NIBIN Lead):.................................................................30 5.7. Low Confidence Correlation Result Notification.............................................................................31 5.8. Release of Results Prior to Issuance of Final Report .......................................................................32 6. Case Record Review ...................................................................................................................34 7. Abbreviations Used in the Firearms Section ...............................................................................37 8. Commonly Used Methods in the Firearms Section......................................................................39 9. Handling of Evidence..................................................................................................................41 9.1. Receipt of Evidence.........................................................................................................................41 9.2. Rejecting Evidence ..........................................................................................................................42 9.3. Repackaging Evidence.....................................................................................................................43 9.4. Release of Evidence ........................................................................................................................44 10. Potential Biohazards and Decontamination..............................................................................45 11. Evidence Log-in ........................................................................................................................47 12. Safe Firearm Handling ..............................................................................................................51 13. Examination & Classification of Firearms..................................................................................53 Firearms Section SOP Document ID: 8898 Issued By: Section Manager Issue Date: October 18, 2019 Uncontrolled When Printed Page 2 of 106 Firearms Firearms Section SOP Comparative & Analytical Division 14. Suspected Loaded Firearms Submitted for Unloading and/or Rendering Safe...........................55 15. Pre-Firing Safety Examination...................................................................................................57 16. Trigger Pull Determination .......................................................................................................59 17. Barrel & Overall Length Measurement of a Firearm..................................................................62 18. Rusty Firearm Examination.......................................................................................................64 19. Malfunctioning Firearm Examination........................................................................................65 20. Bore & Chamber Casting...........................................................................................................68 21. Test Firing And Recovery Methods ...........................................................................................70 22. Primed Cartridge Case/Shotshell ..............................................................................................74 23. Reduced Powder Loads ............................................................................................................75 24. Remote Firing...........................................................................................................................77 25. Firearms Reference Library.......................................................................................................78 26. Caliber/Caliber Family Determination ......................................................................................79 27. Air Gap.....................................................................................................................................80 28. General Rifling Characteristics Utilization .................................................................................82 29. Wadding Determination...........................................................................................................85 30. Shot Determination..................................................................................................................86 31. Physical Examination & Classification of Fired Bullets...............................................................88 32. Physical Examination & Classification of Fired Cartridge Cases & Shotshells .............................89 33. Microscopic Comparison ..........................................................................................................90 34. Trace Material..........................................................................................................................94 35. National Integrated Ballistic Information Network – NIBIN.......................................................95 36. NIBIN Processing ......................................................................................................................97 37. Serial Number Restoration – Polishing....................................................................................101 38. Serial Number Restoration – Magnetic Technique ..................................................................102 39. Serial Number Restoration – Chemical Restoration.................................................................104 Firearms Section SOP Document ID: 8898 Issued By: Section Manager Issue Date: October 18, 2019 Uncontrolled When Printed Page 3 of 106 Firearms Firearms Section SOP Comparative & Analytical Division 1. Introduction The standard operating procedures outline the general protocols used in the examination of firearms related evidence. The procedures addressed serve as guidelines and allow for flexibility in the examination of evidence as dictated by the request from the customer and the condition of the evidence. Handwritten notes, examinations recorded in LIMS (as well as formatted worksheets containing information recorded in LIMS), digital photos, and printouts/digital copies of computer- based search information are utilized