My Side of the Mountain question

It was about a teenager who runs away & lives in the woods. He befriends another teenager named K Man. His dad liked to play "Risk" with him. At the end of the book, he goes back home. One night, his dad pokes his head in the doorway of the boy's room & the teenager is laying in bed pretending to be asleep. He ends up shooting himself with his dad's shotgun.

The book is NOT "My Side Of The Mountain" but it's kind of similar judging by the description I read.