Ammunition Containing Mercury

To clarify the situation regarding mercury-containing ammunition a series of experiments were conducted and casework statistics gathered. 

On other occasions mercury-containing ammunition has been test fired, the hands sampled immediately, the samples analyzed by SEM/EDX, and... 

The particle classification scheme is based on modern primed ammunition and consequently mercury fulminate-primed ammunition is not included. Mercury-containing particles from the discharge of mercury fulminate-primed ammunition are rarely detected in casework. Discharge residue from such ammunition was tested in an effort to provide an explanation for this. Discharge particles from Sintox-primed ammunition was also examined with a view to anticipating future problems the criminal use of... 

To determine the frequency of occurrence of mercury-containing particles in FDR, promptly collected residue from the discharge of mercury fulminate-primed ammunition was examined. Results are given in Table 22.1. In the first firing a small proportion of the particles also contained one of the following elements cobalt (trace), magnesium (trace), nickel (trace), and phosphorus (minor and trace). 

Properly loaded, the two types of primers are almost impossible to distinguish and properly sized should work in any cartridge. Typically Berdan-primed ammunition, especially military surplus rounds, has often used corrosive priming compounds because they are cheaper to use. Boxer-primed ammo now is almost always non-corrosive and non-mercury-containing. 

There is no lead or barium in the primer yet discharge particles from this ammunition frequently contain lead, antimony, and barium. The lead and barium must come from other components in the ammunition (bullet core/propellant) and/or from contamination in the firearm. Tin was also frequently present in the discharge particles and originates from the tinfoil disc used to seal the primer cup in mercury fulminate primers. 

Analysis of the nny 82 ammunition as previously detailed shows that it uses a mercuric corrosive primer. Analysis of the Chinese 351/73 ammunition revealed that it has a copper-coated iron-jacketed bullet with an iron core and a lead tip, the cartridge case is steel with a brown colored lacquered finish, a brass primer cup, and the propellant is single based with DPA, 2 x nitrodiphenylamines, camphor, and contains no inorganic additives, and the discharged primer composition is antimony, potassium, chlorine, mercury, tin, sulfur, iron, manganese, phosphorus, zinc, and lead in descending order (lead, antimony, mercury type). 

The frequent use of both types of ammunition in recent years has substantially increased the proportion of shooting incidents involving the use of mercury fulminate-primed ammunition. It has also substantially increased the proportion of shooting incidents involving the use of single-based propellant. It is worth noting that both propellants contain camphor. 

In casework in which discharge residue particles were detected, and in which the ammunition involved is known to contain mercury, very few, if any, of the particles contained mercury. This has been noted over many years and in numerous cases. Possible reasons for this could be the volatility of mercury and its compounds, or decomposition of the mercury fulminate and the loss of mercury through amalgamation with zinc in the primer cup/car-tridge case. It is not uncommon, when firing old ammunition with mercury fulminate primers, for some of the cartridge cases to crack, due to embrittlement of the brass caused by mercury amalgamating with the zinc. 

This supports the proposition that anything present in a round of ammunition can make a contribution to the composition of the discharge residue particles. The presence of tin in any of the discharge particles is an indication that the primer contains mercury, the tin originating from the tinfoil disc used to seal mercury fulminate. (Tin is also present in some modern ammunition components, for example, Sellier Bellot, and it is present in some propellants.)... 

An ancillary test involved examining discharge residue particles from the ammunition used in the mercury distribution tests. Approximately 260 particles were examined of which 8 contained mercury (about 3%) at minor or trace level. 

The soil samples taken on the 20 September 1993, 2 years later, inside the former ammunition depot yard contain high concentrations of mercury which increases with depth, in contrast to lead, while cadmium was unexpectedly low (Table 21.3). 

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