I was that good as a 14 year old at the peak of my career. There's nothing inherently inaccurate about them. Right arm: bone2bone thumb-cheek weld with forearm parallel to the deck. Left arm: slingshot held sideways, top post used as a shotgun bead. Best ammo: not a sphere. The less aerodynamically shaped an object, the better it will fly because sexy objects can create forces perpendicular to their flight path (aka lift) and thus turn. They also buffet worse. An object with sharp edges such as a 3/8x1 inch bolt or a 7.62x39 empty will fly pretty straight no matter how it tumbles and will not develop any knuckle-ball buffeting. If it produces only drag in every orientation, that's good. Smooth is bad for accuracy. So look for a high density object that isn't smooth that fits the pocket nicely.