Does it have a factory stock on it? I picked up a browning a-bolt in 7mm rem mag at a a gunshow for a great price with a mcmillon stock on it. When i went to the range to shoot it in however i was getting horizontal stringing with each consecutive shot. I tried letting the barrel cool and even only shooting 2 shots it would move poi to the right. I took a piece of paper and with the barel hot could only slide it an inch down the stock channel before it hit. I took it home and opened up the stock channel and now im getting consistant groups in the .8 range at 100 with no stringing. Sorry for the long post but my advise is to see if the barrel is still free floated when warm,
Nick