If the pup is goin that far on his own at 10 months, he will probably only get further with age. I understand that it may be land issues in that you want him to stay close, but you are trying to break the pup from doing what 95% of everybody on here is trying to get their pups to do.
I would suggest throwing that pup into the woods every chance you get to attempt and reach his full range of potential, or selling the dog and getting a line that is shorter range with less bottom. (You won't have to look far).
Or if you want to cull him I would be glad to take him for you.
