flounder33

Since you are indicating the rifle is NEW, I really can not explain in the correct terms what I think you are seeing, but in just ordinary language what I think you are seeing is part of the blueing process(a rusting process that turns the metal blue). Blue is a salt based process that turns metal blue. The longer the process occurs the deeper and darker the blue. Cleaning the feshly blued gun with a quality gun oil can result in a darken patch looking a bit like rust. I have cold blued several guns and get those darkened cleaning patches for several months after blueing.

I know there is a way to neutralize the blueing process and I know oiling will do it eventually, but I am not sure what to use to stop it NOW...

Just my best guess...