I've watched that video with vanilla speed limit exploit and decided to see if I could utilize that in my Gravity Reactive Armor system.
Although I haven't managed to keep auto-welding working with the new structure, I liked the results so far.
Shot energy is about 2 gigajoules and velocity is ~380 m/s. This variant is kinetic, with several blast door fragments. It can be instantly shot at any target in 45 degree cone.
At those speeds vanilla turrets don't react to the incoming threat, and it's really hard to evade. I still have to update my script for lead calculation for uncapped velocities.
Original video explaining the exploit: • Breaking the speedlimit in Space Engineers...