trouble shooting drum brakes

[kevmic28]

I have an issue of the brake peddle moving too far when I hit the brakes and the truck doesnt brake very well. I have replaced the master cylinder, wheel cylinders, new brake hardware, new adjusters, I have replaced everything in the brake system but the drums. Bled the crap out of the brakes but nothing seems to help. I have no idea if the drums are original or not so they may be way out of spec but I need some ideas before I throw more money at it.
I have no signs of the wheel cylinders leaking either.

Im thinking a bad master cylinder or drums too far out of spec.
Any other ideas would be appreciated.