Lead Styphnate
Definition
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 identified by SEM-EDS in GSR analysis.
- Chemical formula
- Pb(C6H(NO2)3O2) or Pb(C6H(NO2)3O2)·H2O (hydrated form)
- Role in firearms
- Primary explosive initiator in small-arms primers
- Combustion temperature
- 1,500-2,000 degrees Celsius
- GSR signature
- Forms lead-barium-antimony (Pb-Ba-Sb) triad particles detected in gunshot residue
Common questions
What is lead styphnate and where is it found?+
Lead styphnate (lead 2,4,6-trinitroresorcinate) is the primary explosive used in conventional firearm primers. When a gun is fired, the impact of the firing pin ignites this compound, initiating the chain reaction that fires the cartridge.
How does lead styphnate help with GSR analysis?+
During firing, lead styphnate combusts at extremely high temperatures (1,500-2,000 degrees Celsius), creating molten droplets. These droplets combine with barium nitrate and antimony sulfide from the primer mixture, forming the characteristic three-component lead-barium-antimony particles that forensic scientists identify using SEM-EDS microscopy.
Why is the lead salt form preferred in primer mixtures?+
Lead styphnate is chosen for its reduced electrostatic sensitivity, making it safer to handle during manufacturing and less likely to detonate accidentally from static discharge.
Related terms
- 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...
- Antimony Sulphide
- Sb2S3, the primary fuel in conventional primer formulations, burning rapidly in the presence of oxygen released by barium nitrate during ignition.
- ASTM E1588
- ASTM International standard practice for gunshot residue analysis by scanning electron microscopy with energy-dispersive spectrometry. Defines particle classification (characteristic, consistent-with, indicative), morphology...
- 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 Particle Search (APS)
- A software-driven SEM mode that scans the entire stub surface using backscattered electron contrast, flags particles above an atomic-number threshold, and triggers...
- 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...
- Barium Nitrate
- Ba(NO3)2, the oxidiser in conventional primer formulations, decomposing thermally to release molecular oxygen that sustains the combustion of antimony sulphide fuel.
- Berdan Primer
- Primer design where the anvil is integral to the cartridge case; primer cup contains only the explosive compound. Identified by two offset...
- Boxer Primer
- Primer design with a self-contained anvil inside the primer cup assembly and a single central flash hole in the case. Standard for...
- 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...
- Characteristic Particle
- ASTM E1588 category: a single particle in which Pb, Sb, and Ba are simultaneously detected by EDS, with morphology consistent with melt-and-quench...
- Consistent Particle
- ASTM E1588 category: a particle containing two of the three primer elements (Pb-Sb, Pb-Ba, or Sb-Ba), or all three elements without spherical...
Explained in these topics
- GSR Composition and Particle MorphologyLead 2,4,6-trinitroresorcinate; the primary initiator in conventional small-arms primers. Its combustion at 1,500-2,000 °C produces the molten Pb-Ba-Sb droplet...
- Gunshot Residue: Three-Component Particles and SEM-EDXPb(C6H(NO2)3O2)·H2O, the primary initiating explosive in conventional primer mixtures, sensitive to mechanical impact from a firing pin. Its lead salt form is...
- Propellants and Primers: Chemistry, Classification, ManufacturingLead trinitroresorcinate (Pb(C6H(NO2)3O2)), the primary explosive in conventional primer compounds. Co-oxidised with barium nitrate and antimony sulfide to pro...