I am pretty anal when it comes to cleaning the barrels of my pistol (Wow, no pun intended although I sure just set myself up for one).. I just can't seem to get it looking spotless and shiny inside. It still has a rough cloudy finish to it no matter how many times I run the brush through or how many solvent-soaked wads I put through it. It almost looks like there's still a fine powdery build up coating the inside. Is this pretty normal even for a gun with only 300 through it?