Regular readers may remember a previous post about a water rocket that is built like a HPR rocket. The rocket flew twice, once with good recovery and once with a failed recovery. Both flights were very fast and achieved about 1000 feet apogee. Most impressive is the amount of thrust, and the short duration. This rocket shows similar performance to a G250 motor in my estimation. Acceleration was around 50 gs, which is more than most high power flights. It is possible that the motor was faster still, perhaps something like a G400. More data would be interesting to find out exactly what thrust and impulse this motor puts out. Here is footage of the two flights:
You can see a detailed flight report here.