The Hatteras cast is a unique cast that developed to serve a a specific need - casting for good distance in a shoulder to shoulder crowd of drum fishermen.
The HC was the first powercast I learned back in the mid 90's. Compared to other casts like the groundcast and the pendulum cast it is very compact and happens quickly start to finish. What this means to the caster is a very timing critical cast. The best way (IMHO) to perfect the HC is to spend some time learning the groundcast. By practicing getting the arms away from your body and in the right position for the push / pull "hit" at the end you will develop a skill that will help with any cast. Since the HC happens so quickly, you need to develop muscle memory that you can count on to get that left hand up and out.
If you watch guys throw the HC, even guys that hit it good, most keep the left arm tucked in nice and safe close to the body and just smack it with the right (right hand caster). It looks impressive and you can get distance if you're big and strong but only 50% of the available "arm power" is being tapped.
To really get the most distance from the HC (or ANY powercast) you must involve the left. Getting good extension and then pulling aggresively when the left is out in front of your face is like adding a turbocharger to the cast without adding a tremendous amount of effort. It is not natural for most of us and does take practice to perfect.
It is time well spent.
Tommy
ps, puppydrum45, take dawgfish up on his offer. He's a very experienced hastteras caster and can help you improve.