Double-Base Powder
Definition
A smokeless propellant combining nitrocellulose and nitroglycerin (10-40% NG by mass). Higher energy density and flame temperature than single-base; standard for handgun and shotgun propellants. Examples: Alliant Bullseye, Vihtavuori N310.
- Composition
- Nitrocellulose plus nitroglycerin
- NG content
- 10 to 40 percent by mass
- Typical use
- Handgun and shotgun propellants
- Examples
- Alliant Bullseye, Vihtavuori N310
- Compared to single-base
- Higher energy density and flame temperature
Common questions
How does a firearms examiner distinguish double-base from single-base propellant residue?+
Analysts typically use gas chromatography or infrared spectroscopy to detect nitroglycerin alongside nitrocellulose in the residue. Its presence confirms a double-base formulation, which narrows the pool of commercial products consistent with the recovered gunshot residue or unburned powder grains.
Why does higher flame temperature matter for double-base powder in casework?+
Higher flame temperature increases barrel erosion and can affect muzzle flash and residue deposition patterns, which examiners factor in when interpreting stippling, soot distribution, and distance determinations at a shooting scene.
Related terms
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- Single-Base Powder
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- SINTOX
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