If you brush your barrel well after firing, there really isn't a need for a copper solvent or a lead one. (Your brush should scrub the residue off). Now if you wait and fire your gun for like 3000 rounds or so, then you'll need to use a solvent.
I run patches down my barrels until they aren't BLACK. Usually a light gray is fine with me. I then run a patch of CLP down the barrel to coat the barrel with a light oil. I also take my semi's down and clean the gas port.
2006 Mustang GT