Hi Colin,
Agree about the distance for surface ships. More the fun. If things become easy then they become boring! Not sure about chucking rocks and stones from the bank but could see it working within a given set of rules. I don't think it could happen though, Health&Safety, Councils complaining about clogging up ponds, wild life enthusiasts and fishermen complaining, and finally the public image of model boaters chucking bricks!
Followed your link. Brilliant if your brain is in Chess mode (and I do enjoy chess)!
Just to recap, I imagine a none damaging sport where we all go home at the end of the day with complete models and the paint balls are environmentally friendly (done some research and will post separately).
One last comment about distance, if this were ever to happen, while the surface lads are messing about at 100 yards, M1 will surface and blat the enemy from 3 feet as intended!
Len