Cayugag, I did a test with the MX BC on my 2 brand new ACCURA Barrel's. Since they have never been used I wanted to treat them and also see if anything came out of them. Being Bargara Barrel's and having been polished with Diamond Tipped Bits to a mirror like finish, I wanted to see if the MX pulled anything out. I applied the MX BC to some patches, ran them through the barrel a few time each patch, then dry patched. The dry patches came out a little (silver) in color, not too much just a little. So I repeated the process with the MX BC and left them sit overnight. The next day I ran a few more dry patches through, and the same thing. Being new, what might the MX be pulling out? Could it be small dust like fragments from the barrel finishing process? I put more MX BC through them, let them sit another day and dry patched, this time the patches were clean and the barrel's were so shinny inside that it hurt my eyes looking through them at a lightbulb. I still have'nt tried the test on the MX on shooting and the results as the weather around here is still cold and snowy & windy.