This topic hasn't got much action. Is it because everyone does it like Grit or is it because not many even index the bores?
The effect it has on the direction the bullet goes.The effect? I guess you need to clarify the effect on what?
3 inches at what distance?So from centerline of barrel if it curves up .010" we could calculate a 3" point of impact error from what a perfectly straight barrel would produce, Theoretically.