1st post
I'd stay away from steel brushes as they can erode/scratch the steel on your gun. I reserve using copper brushes for exceedingly dirty jobs like cleaning mil-surp guns or otherwise abused firearms that have suffered years of neglect. Copper being softer than steel, you shouldn't experience any noticeable wear but I rarely find a need for them in my everyday guns. Also, copper brushes should never be used with a copper removing solvent as it eats away the brush and leaves behind a blue-green color on the patch. This could fool the user into thinking that their barrel isn't clean when it's really the eroding copper brush leaving the tinge of color.
95% of my handgun cleaning is done with nylon brushes wrapped with a patch, brake cleaning fluid for the action (keep away from plastic, wood and rubber, but composites should be fine), copper solvent for the barrel and then lubed with Mobil 1 Full Synthetic 20W-50. Use the oil sparingly. Enough to coat the friction bearing surfaces, but not so much that it becomes a dirt/dust magnet. Never a problem in 30+ yrs of shooting.
Wrapping your nylon brush with a patch will retain more copper solvent and keep it where it belongs, at the ends of the bristles and deep within the rifling of the barrel. From what I can tell by the smell, high evaporation rate and effectiveness, the same solvent in aerosol gun/action scrubbers/cleaners is used in aerosol brake cleaners for much less $ at the auto parts store.