DDNP (Diazodinitrophenol)
Definition
A lead-free primary explosive used in some lead-free primer formulations. Produces strontium-antimony or tin-containing GSR particles depending on the oxidiser used.
- Class
- Primary explosive, lead-free
- Use
- Lead-free primer formulations for firearm ammunition
- GSR signature
- Strontium-antimony or tin-containing particles, oxidiser dependent
- Driver
- Reformulated to remove lead-based primer compounds
- Analytical relevance
- Requires updated GSR elemental reference profiles beyond lead-barium-antimony
Common questions
Why does DDNP-based ammunition matter for GSR analysis?+
Traditional GSR analysis targets lead-barium-antimony particles from conventional primers. DDNP-based lead-free primers do not produce that classic composition, so an examiner relying only on the old signature could miss residue from lead-free ammunition entirely.
How can an analyst tell DDNP-based residue apart from other lead-free formulations?+
The elemental composition of the particle depends on which oxidiser was paired with DDNP, so examiners look at the specific combination of elements present, such as strontium with antimony or tin, alongside particle morphology, rather than relying on a single fixed profile.
Related terms
- ASTM E1588-20
- ASTM International standard guide for gunshot residue analysis by SEM-EDS. Defines characteristic, consistent, and commonly-associated particle categories and sampling, analysis, and reporting...
- Automated SEM-EDS
- A robotic scanning electron microscopy workflow using backscattered electron imaging for morphometric screening and automated EDS acquisition for elemental classification. Reduces analysis...
- Characteristic GSR Particle (ASTM E1588-20)
- A particle containing lead, barium and antimony together by SEM-EDS, with spherical morphology and size in the 0.5-10 micrometre range. The highest-specificity...
- Lead Styphnate
- Lead trinitroresorcinate (Pb(C6H(NO2)3O2)), the primary explosive in conventional primer compounds. Co-oxidised with barium nitrate and antimony sulfide to produce the Pb-Ba-Sb triad...
- Organic GSR (OGSR)
- Propellant-derived residues including nitroglycerin, 2-NDPA, 4-NDPA, ethyl centralite and nitrocellulose fragments. Analysed by HPLC or GC-MS, independent of the inorganic SEM-EDS workflow.
- SINTOX
- A lead-free, heavy-metal-free primer formulation developed by DAG (Deutsche Ammunitions- und Geschossfabrik) and Geco in Germany in the 1990s-2000s, replacing lead styphnate...
- Ternary Diagram (Pb-Ba-Sb)
- A triangular compositional plot with Pb, Ba and Sb at the three vertices. Particles from conventional primer discharge cluster in the centre;...