by sleightlycrazy » Jun 3rd, '07, 17:49
A video might be helpful in determining the issue.
I started off by shooting it sideways. I was able to shoot it a good foot to the side when I started shooting it up. Consistent practice (that drove no less than three of my teachers nuts, got me to shoot the coin a foot and a half up.
Basically, it's probably just lack of practice.
http://www.coinvanish.com/
The "Foundations" section of the above link has good tips on the muscle pass. I'm not sure if it's what you need, but I hope it helps.
Currently Reading "House of Mystery" (Abbott, Teller), Tarbell, Everything I can on busking