I liked the sound of this so I ran up this version to see if I could get it to work.
As @jonathan says, Hype is well suited for this. But you need to add some JS and manually set the inputs.
I threw this together while I had 10mins here and there so it probably could be written simpler!.
One thing I may look at is stop shots that do not hit the target which I thing should be easy now I have the main code down. But you may want some to miss??.
targetArea.hype.zip (40.1 KB)
I have left the score numbers I was using on the target but you can simply take those off
Update, In this one the shots do not miss the target..
targetArea v2.hype.zip (40.3 KB)
Again quickly done so probably could be tided up