Anyone had problems with corrosion around the gas ports. I have shot my 556 very little. I use factory, non-corrosive ammo, and yes, I clean my rifle after shooting it. It has been a few months after my last shooting/cleaning session. Upon stripping the rifle down, I observed that it has corrosion in the lower inside part of the ring through which the gas tube passes. It is corroded around the ports. There is discoloration (not carbon buildup) on the bottom of the gas tube where it lines up with the ports as well. I only use a cotton cleaning patch and Break Free in this area. I have always wiped this area clean before reassembly. I also observed some discoloration on the top of the barrel where it comes out of the front of the gas block. This is directly below the knurled ring on the gas tube. This is frustrating to see this. There is no corrosion anywhere else. I use this ammo/cleaning combination with other rifles and have had no problems. I do take care of my firearms. This is not from any neglect. I would really like to know if anyone else has had a similar issue. I've yet to contact Sig about this, but I will. Thanks in advance for any feedback.