As with any other throwing style, you're using too much arm strength to throw, which isn't going to help you and could result in serious injury if you don't stop. Also, this is a throw you should build up slowly, since you will need to build muscular coordination that you don't already have (unless you're an active baseball player). Start with very light plastic (e.g., Blizzard 130g). Go to a field, try throwing 100 times but only aiming to hit 100 ft. Remember, your body's stupid instinct is to put more muscle into the effort if you're not getting the distance, but it is actually the worst thing you can do. Keep your arm loose and whip it forward using the strength of your torso alone. Push off your back leg to gain forward momentum, and then push back from you plant foot to accelerate the hip turn (your back leg pushes that side of the hips forward and your plant leg pushes the other side of the hips back...this is the fundamental twist force). This should uncoil in sequence up to your shoulders...that's where all the strength lies. The rest is positioning and timing with the arm, but just remember to open the hips almost completely before the disc begins moving forward.
Drivers: Starlite Wraith (158g), Gummy Champion Leopard (150g), 1st Run Z-Talon (150g)
Mid-Range: Star Classic Roc (146g), R-Pro Roc (157g)
Putt/Approach: Legacy Protege Clozer (158g), Glow DX Aviar (150g)