För koppar kan jag rekommendera:
M-PRO 7™ COPPER REMOVER

Ammonia-free formula works fast to dissolve and strip out stubborn copper fouling caused by high-velocity, copper-jacketed bullets
used in varmint, tactical, and competition guns. Helps restore accuracy to neglected bores and conditions the steel to reduce future
copper buildup. Won’t etch or pit barrel steel, but should not be used on brass, aluminum, and blued or plated surfaces.
Odorless,
environmentally safe, biodegradable, non-toxic, and non-flammableKör den själv i mina bössor och pistoler.