how do i stop my boat swinging round on the anchor ? it causes me problems when i\'m uptiding or anchoring over a wreck i\'ve thought of using 2 anchors 1 over the stern and 1 over the bow but i think this might be a bit dodgy if there\'s a bit of a swell or maybe tying an old car battery or breezblock onto some rope and hanging it off the back of the boat any sugestions ?