I bought one off of Gunbroker, it wouldn't shoot worth a darn. So I had D-tech build one, I spent a considerable amount of time finding a subsonic 220gr load that would shoot better than 3 or 4 inches. I finally developed a load that would shoot an inch with 220gr sierra BT. I had to match headstamps, then sort by weight, trim to exactly same length. I lost every coyote I shot with the 220's, tracking one for well over a mile on hard packed snow even though I had shot it through the chest. With supers I killed a couple, a 125gr TNT did a very fine job.
Haven't shot mine now in several years, the upper hasn't even had a scope on it in many years. Its for sale if someone wants one.