Start with the easy stuff first then get into the gunsmith items. I would clean the barrel with a good cleaner for powder/ead fowling and then a dedicated copper remover. Then check your scope mounts. Also ammo comparison should be done. Like others mentioned what do you normally shoot, it 3" then you need practice but can still try the above as well. Have someone watch you shoot to ensure your not peeking, jerking the trigger, putting pressure on the barrel, flinching, etc.

Then you can investigate the gunsmith work. A trigger job would be advised on most factory rifles(if adjusted for pull and travel it should be relatively inexpensive no more than 30-40 bucks tops. however if you want to replace it will be considerably more dependant on the brand of trigger), have the smith check for stock/barrel contact and then you can explore other options and actual costs.