I just clean my brushes in water
most solvents are water soluble, the ones I use are
I dry the brushes out properly after but don't have any problems with doing it under the tap and they do come out very clean
when getting copper out I look down the muzzle looking for evidence of copper, I don't go by the clean patch so there is no copper theory
I also polish the throat of my barrels usually between around 200-300 fired rounds, stops the roughness from fire cracking ect... works for me
I like to use bore tech eliminator for bad cooper, it works very well and you can leave it in the barrel
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