Battle Drills. Kill Zone (en Inglés) - Shane Gries

Dave Hernandez survived the war. He’s not sure he’ll survive the peace.

Two years after the armistice, the former Terran Marine works aboard aging freighters in the Zone of Separation, a lawless region where interstellar patrols are gone and pirates operate freely. When Khavan raiders board his ship, his combat training takes over, and the mercenary company guarding the cargo offers him a job.

Jackson Solutions Unlimited, "the Jacks," are underfunded and hard-bitten, and their contract with Brightstar Shipping is killing them:

Someone is feeding the pirates perfect intelligence, and the trail leads to the top of the company that hired them. With warrants out for their arrest, the Jacks mount one last operation: infiltrate a billionaire’s estate, seize the man behind the betrayal, and get out before the planet’s security forces close the door.

Battle Drills: Kill Zone is military science fiction written by a thirty-year U.S. Army infantry officer, with authentic squad tactics, a mercenary company you’ll want to serve with, and a hero who learns what it costs to lead.