This pack from Maxpedition Hard Use Gear is designed to carry a lot of gear without taking up too much space. There is a pocket for hydration gear and a concealed firearm pocket, so this bag can carry everything you need.
Specifications and Features:
2810 cubic inches (46 liters) of carry capacity
Three compartments equipped with YKK #10 zippers and paracord knot pulls
Comfortable back padding
Supple curvaceous straps