Herein we describe cartridges, including for shotgun shells, utilizing a particulate obturating medium to provide a gas seal. The obturating medium comprises particles having an average particle size greater than 212 microns, and an average specific gravity greater than 1.1. Such cartridges are particularly useful as shotshell cartridges used as blanks, less lethal loads, hunting loads, target loads, and barrel-cleaning loads. Methods for loading and use are described, as well as different particulate obturating media.