I have a new Marlin 94 in 45 C, I took it out and shot 100 rounds through it and when I came back and got ready to clean it the inside of the bore was gray. I have scrubbed on it about 2 hours with brass bore brushes and solvent. I even tried a Lewis Lead remover and its not coming out. The rounds fired were Cast Performance 260gr LBTGC with 18.5 and 20.0 grains of 2400. These rounds shoot very well in my Ruger RH and there are no signs of pressure. My question is if this is lead in my barrel what do I use to get it out and could the barrel be defective or is it just rough. The bullets were sized .452 and I am checking with Marlin to see what size the bore should be. These rounds don't seem to lead in my revolvers so I am at a loss. I would appreciate any help or advice you might have concerning this problem.