Your target states that you have a magazine problem. Are you loading from the magazine or are you loading each round directly into the chamber? Could be you're damaging the tip of the bullet. Or, like JGFL said you may have a hot barrel if you're shooting too fast. Shoot 2 next time then let the barrel cool for about 10 mins and shoot another 2. Also be sure your rifle rest on the sand bags at the same place on the forearm (I like to put my hand between the forearm and the bags) and that you use the same cheek pressure on the stock. These little things can cause fliers. Inconsistency is the best way to screw up a group.