I had to send my rifle in also, I haven't even fired it yet. I started getting corrosion on on the top of the bolt and after I would dry fire it the bolt lift was very stiff. When I talked to Cooper and told them about the corrosion they said they were aware of it and had changed the finishing process. They said it was a fairly common issue. Then I told them about the very stiff almost difficult to open bolt and they said that is a less common issue and then they sent me a UPS call tag. I sent if off a couple days before Christmas and I don't have it back yet.