A pull-through applicator assembly for maintenance of a gun barrel. The pull-through applicator assembly is a unitary, disposable, and configured for easy manufacturing relative to conventional pull-through assemblies. The economics of the disclosed pull-through applicator assembly is sufficient to permit packaging and sale as a disposable unit, for discarding after a single use. The single-use aspect enables the fibrous body to be configured primarily for compliance to the internal geometry of the gun barrel (e.g., the grooves of the rifling) without need for considering the durability over multiple uses. Accordingly, enhanced contact with the internal geometry of the gun barrel is realized in the convenient form of a pull-through applicator that is disposable. The pull-through applicator may be configured of biodegradable materials to enhance the disposable aspect.