As has been said the first thing you should do is a thorough cleaning ensuring you get all the fouling powder and copper cleaned up. Then buy several boxes of cartridges in different weights and bullet types. Make sure that your rings and bases are tight. Then have someone else shoot your gun to see if they can do better. Then start looking at making changes to the gun. First change is a trigger job or a replacement, bringing your pull weight down from the factory lawyer trigger will do amazing things to your groups. As long as your happy with your stock I wouldn't touch it unless you absolutely have to. The most you may have to do is open up your barrel channel to free float the barrel, just make sure it is necessary first some guns like to have the pressure point others don't.