AFTE Store - The Source and Persistence of Lead in Gun Barrels

Heavy metal-free (HMF) primer compositions are in common usage in Europe and are becoming ever more common in the United States with all major ammunition manufacturers offering HMF product lines. The increased use of these HMF compositions stands to reduce and ultimately eliminate the presence of lead in gunshot residues and in traditional bullet wipe around the margins of bullet holes. However, considering the long shelf life of ammunition, cartridges with traditional lead styphnate primers will continue to appear in casework for many years to come. This research addressed the situation where a pistol barrel has been fouled with lead-containing ammunition after which one or more rounds of heavy metal-free ammunition are fired. Previous testing by the authors has shown that lead is still detectable in bullet wipe after the discharge of as many as 50 rounds of HMF ammunition. Questions regarding the source of this lead and its persistence are addressed in a relatively simple experiment wherein sections of a lead-contaminated 9mm pistol barrel were removed and examined by SEM/EDX before and after the discharge of 30 rounds of HMF ammunition.

Full Journal: AFTE Journal Vol 39 No 1 (2007)