We were quite pleased with our turret... it had 300+ degrees of rotation and about 45 degrees of tilt, and worked flawlessly all season.
If only the mechanism that loaded balls into it had done the same. Sigh.
In any case, we used an aluminum lazy susan bearing from Lee Valley Tools
http://www.leevalley.com/wood/page.a...50,43298,43316
The balls were loaded by a belt drive through the centre of the lazy susan.
Jason
Oh... yeah... we used a globe motor (with a 1" dia. pulley on it) to turn the turret using a 1/4" thick 15" dia. o-ring stretched around the outside of the lazy susan.