The system that I am working with can be seen at the following website
It is proving to be very reliable, easy to operate and excellent shooting practice. I have used it so much that some improvements came to mind that made it even better.
In a nutshell the system is composed of a pair of bases into which 6' pieces of 4x4 post are placed. The bases are spaced 100 feet apart. On top of one post is a winch containing 100 feet of plastic coated steel cable (standard boat trailor winch). This cable is stretched over to a hook on the other post, making a guide-wire for a target holder to roll back and forth on.
On the other post is a 1/2 horsepower electric motor that is powered by 110, so you need a portable generator. The electric motor runs a second cable or twine, this one used to pull the target carrier back and forth on the heavier steel cable. The controler simply varies how fast the target runs and which direction it goes.
I use full sized cardboard cutouts of deer, large cardboard rectangles (cut from refrigerator boxes etc) with balloons in the middle, ShootnSee targets - about anything that you want to shoot at.
We have 100 yards of power cable now, so the controler is back of the shooter. ALthough this might sound complicated it is a very simple, rugged, easy to operate system that has proven great for learning to hit moving targets. The motor will move the targets much faster than anyone could hit them.
I have a lot of photos of the system operating, I will get a couple scanned when my son is back from a holiday and maybe Len can put them on this forum.
Cost is about 1500 bucks for this system, it is ready to go as received. I can see two or three guys going together or a club buying one, it is worth obtaining as the target speed is repeatable, all the components are super well made, system is foolproof (ianproof).