I was shooting lots of lead this weekend. While I was shooting at a can 125 yards away I was watching the pellet in its travels. Pretty cool until I started seeing the pellet swirling around down range. It was very pronounced. Then I realized the barrel was probably filthy after shooting the 49 grain hunters supply bullets. I pulled patches thru on a piece of weed wacker string and it never stopped being dirty. The gun shot better but is there a product to us to clean the barrel and not harm it?