[bobdahaxor]

as I ranted in one article, be careful. Springs are dangerous, and you need to pull them back. Even the 2" bores can only produce a maximum of 189 pounds(foot pounds?) of force/ energy. This is going outwards not inwards which is what you need. so at @ 180 b/c you loose energy to heat, a bullet produces at a minimum 1000J. in reality, do you want the energy of a .22 firing your ball upwards? if you ever have fired a gun, .22 is an oversized BB gun essentially.