I have trouble getting the copper filing out of barrel of my rifles.I shine a light in muzzle and can see it so I assume it is all the way down.Is Hoppes copper solvent the way to go?Any pointers on gun cleaning are always welcome.
I use Hoppes Bench Rest 9 Cooper solvent. Trick is to let it soak in and work for at least several hours, even over night if fouling is heavy. Use a new bore brush and then wet patches. Repeat until you no longer get any green on your patches.
If you can see it keep on scrubbing. Some bullets are worse then others. Few years ago I was testing some Swift Senn. and it fouled so bad I thought I toasted my barrel. Went back to the basics of trouble shooting of cleaning it settled back in.
I use a copper/powder solvent called BoreTech. It is a foam that you squirt down the barrel until it comes out the end. I let it sit for at least 15 minutes and then start scrubbing the barrel out with a nylon brush. I am always amazed at the amount of crud that comes out. After scrubbing it out I just run patches down the bore until they come out clean. Once they are clean, I just run a lightly oiled patch down the bore.