"I have experienced much longer accurate life from a barrel using TMS, and much easier cleaning. It's a hard concept to accept for some people, but it's true: the more frequently this product is used the relatively longer the barrel will last." - David Tubb (11 time NRA National High Power Rifle Championship) As most competition shooters know, barrel erosion is the number one cause for accuracy loss. These bullets are coated with a unique polishing compound that increases barrel life and accuract at the same time.