So my old time favorite rifle, 270 wrby mag is going into retirement and stored for my grandson who is now just 3. My grampa bought it for me as a graduation present 38 yr ago, its been shot alot and has always been kept clean and oiled, but after all these years I know there is a certain amount of dust and oil residue in everything from the trigger assy to the bolt itself. my ? is should I just clean normally or spend the cash and have it dismanteled and cleaned by a gun pro and store. Thanks