Phillip J Tucker 
Gun Barrel Planets — Planet Salvation (Book 1) 

Planet Salvation Simon is a brilliant young man with a thirst for knowledge. With his aging grandfather, Mike, a hero of the third World War, he seeks to unlock the secrets of an ancient alien device. With an honesty shaped by his naivety, he changes not only the future of the human race, but the surrounding Galaxies as well. Of course the problem with change, as many leaders throughout human history have found, often to their peril, is that not everyone wants to. Unfortunately Simon will learn the hard way, that when you’re facing an enemy, your back is exposed.