I just purchased a brand new GP100 on Sunday, haven't fired it yet. I was just looking at it and, for the first time, used a small flashlight to look down the inside of the barrel (I know, should have done that at the shop before I bought it). Tonight I noticed what looks like light rust or corrosion on the inside of the barrel, especially by the cylinder. I have not given it a cleaning yet, because I wasn't planning to take her to the range for a week or two. My question is, is this normal? Is it permissible to have some corrosion on the inside of the barrel, or did I get sold a lemon? The rest of the gun looks great. Thanks for any input!