This book contains target diagrams to use at the gun range when sighting in your rifle with a new scope, optic or hard sights. You can mark in this book where your bullet hits the target down range in order to track your point of impact to zero in your scope for various distances. This is important for hunting in the woods or shooting at the range competitively in a marksmanship long shot sniper competition. This works for all firearms, rifles, pistols, air soft, bb, pellet and even paintball markers.