Big hint: more dialogue, less narration.
Also, it's pretty obvious in two or three places that you have no idea what you're talking about. Like the fact that a klick is a kilometer, so taking a 13,000 meter shot is juuust a bit stretching the range of a .308, which isn't choice for more than an 800m shot, and hiking 367 kilometers through enemy territory, which is roughly equal to walking the roads from Phoenix to Vegas. And Irvan switches branches of the military halfway through his backstory... first it's Army 101st Airborne, then Marine Scout Sniper school, then back to the Army for the Rangers. And I won't even get into the guns, but you seemed to go out of your way to name as large a variety of firearms as you could.