Sep 1, 2026

US12723009 - Propellant charge

The invention is directed to a propellant charge for guns, to a combination of a propellant charge and a primer, to a firearms cartridge, and to a method for modifying the surface of a propellant charge. The propellant charge of the invention comprises multiple propellant grains, wherein an exterior part of part of the propellant grains has been subjected to a surface modification treatment comprising the successive steps of suspending propellant grains in water to prepare a slurry, adding an organic solvent to the propellant grains before, after and/or during the preparation of the slurry, mixing the slurry that comprises water and organic solvent for a period of 120 minutes or less, lowering the concentration of organic solvent, removing organic solvent, and drying the propellant grains to remove water; wherein part of the propellant grains has not been subjected to the surface modification treatment.

Assignee: Nederlandse Organisatie voor toegepast-natuurwetenschappeliijkonderzoek TNO
Inventors: Christoffel Adrianus Van Driel
Filing date: 2024-11-15

propellantfirearmammunitioncartridge

The invention pertains to a method for modifying the surface of propellant grains used in firearms cartridges, involving a series of steps that include creating a slurry with water and an organic solvent, followed by drying the grains. The resulting surface-modified propellant grains are designed to be combined with a primer, optimizing the pressure buildup time during ignition.

Claim 1

1 . A method for modifying the surface of propellant grains, wherein said method comprises the successive steps of suspending propellant grains in water to prepare a slurry, adding an organic solvent to the propellant grains before, after and/or during the preparation of the slurry, mixing the slurry that comprises water and organic solvent for a period of 120 minutes or less, lowering the concentration of organic solvent, removing organic solvent, and drying the propellant grains to remove water so as to obtain surface modified propellant grains, wherein said surface modified propellant grains are combined with a primer, wherein the time required from the first gas generation of the primer until 10% of the total pressure has built up is in the range of 0.2-20 ms. suspending propellant grains in water to prepare a slurry, adding an organic solvent to the propellant grains before, after and/or during the preparation of the slurry, mixing the slurry that comprises water and organic solvent for a period of 120 minutes or less, lowering the concentration of organic solvent, removing organic solvent, and drying the propellant grains to remove water so as to obtain surface modified propellant grains, wherein said surface modified propellant grains are combined with a primer, wherein the time required from the first gas generation of the primer until 10% of the total pressure has built up is in the range of 0.2-20 ms.

Google Patents

https://patents.google.com/patent/US12723009

USPTO PDF

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/12723009