Had a similar issue with an older pre-Monarch 3-9×40....sticking variable ring. They replaced it with a new Monarch 3 2.5-10×42. Good trade on my part but if I was trying to scope a lightweight rifle it wouldn't be my first choice. I'd submit a claim and send it back in and follow up with a phone call to make sure you get a choice on replacement if they decide to do so.
