Cellulose-Based Propellant for Smokeless Small Caliber Firearms
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing propellants for small caliber firearms, such as black powder and its mineral-based substitutes, suffer from issues like smoke emission, residue fouling, hygroscopicity, and inability to withstand high pressures, making them unsuitable for modern firearms that require consistent performance and safety.
Innovation Solution
A cellulose-based organic fuel combined with a non-azide, nitrogen-containing primary oxidizer and a secondary nitrate, perchlorate, chlorate, or peroxide oxidizer, formulated to produce mostly gaseous combustion products, reduce hygroscopicity, and maintain a pressure-time profile similar to black powder, while being extrudable and controllable for consistent performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If black powder or mineral-based substitutes are used in small caliber firearms, then the propellant can be used in low-pressure weapons, but it produces smoke, residue fouling, and is hygroscopic
Solution Approach 1:
The patent changes the chemical composition parameters by using organic oxidizers (nitroguanidine, triaminoguanidine, diaminoguanidine, monoaminoguanidine, or nitroaminotetrazole salts) instead of mineral-based oxidizers. This parameter change transforms the combustion characteristics to produce mostly gaseous products with minimal solid residue, while the organic nature of all components reduces hygroscopicity and improves reliability in varying humidity conditions
Solution Approach 2:
The patent creates a composite propellant formulation combining organic fuel (cellulose, nitrocellulose, or other organic compounds) with organic oxidizers in specific ratios. This composite material approach allows optimization of combustion efficiency, smoke reduction, and hygroscopicity simultaneously, achieving a propellant that burns cleanly with minimal residue while maintaining low pressure characteristics suitable for small caliber firearms
2Object-affected harmful factors
If high energy smokeless powders are used, then smoke emission is reduced, but the chamber pressure becomes too high for many sporting guns
Solution Approach 1:
The patent adjusts the energy density parameters by selecting organic oxidizers with lower decomposition temperatures and controlled burn rates. The specific choice of oxidizers (nitroguanidine, triaminoguanidine, etc.) and their ratios to fuel components are optimized to reduce combustion chamber pressure while maintaining smokeless operation. This parameter optimization allows the propellant to function in low-pressure sporting guns without producing smoke
Solution Approach 2:
The patent applies local quality by designing the propellant with specific fuel-to-oxidizer ratios that create controlled combustion characteristics. The organic oxidizers are selected and proportioned to ensure complete combustion with minimal residue while maintaining pressure levels appropriate for small caliber firearms, achieving both smokeless operation and pressure compatibility
3Ease of manufacture
If mineral-based oxidizers and fuels are used in propellants, then the propellant is easier to manufacture, but it produces smoke and fouling and is hygroscopic
Solution Approach 1:
The patent changes the material composition parameters from mineral-based to organic-based components. The organic oxidizers and fuels are selected to provide complete combustion with minimal residue, eliminating smoke and fouling issues. While organic materials may require different handling and processing, the patent demonstrates that these materials can be manufactured into effective propellants for small caliber firearms with improved combustion characteristics
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution provides a smokeless, residue-free, and non-hygroscopic propellant with consistent ballistic characteristics and temperature insensitivity, suitable for small caliber firearms, ensuring reliable operation and easy cleaning, even in extreme weather conditions, with reduced sensitivity to chamber pressure and improved safety features.
Implementation Method 1
the temperature of combustion is at a level that provides substantially complete combustion of the propellant during firing, preferably before the projectile leaves the muzzle, so that the products of combustion are mostly gaseous
Data Source
AI summary
Propellant compositions are provided herein for use in small arms cartridges. Such propellant compositions include a cellulose-based organic fuel, a non-azide, nitrogen-containing primary organic oxidizer and a secondary nitrate, perchlorate, chlorate of peroxide oxidizer. Preferably, such compositions are in the form of extruded shaped hollow cylindrical grains having dimensions that makes it loadable in a muzzleloader firearm or small calibre firearm cartridge case. Ignition grains are also provided for use alone or in a mixture with the propellant compositions. When used in a small calibre firearm or muzzleloader, the temperature of combustion is at a level that ensures substantially complete combustion of the fuel during firing so that the products of combustion are mostly gaseous.