Electromagnetic Rail Gun Scaled Back To Fire 50 to 100 Nautical Miles
Rear Adm. Nevin Carr told Inside the Navy during a break in a congressional hearing on March 1 that the sheer physics of the system makes it inefficient to push the weapon past 32 Megajoules, which the system prototype has already achieved in test shots.
"Turns out there's kind of a knee in the curve of cost versus benefit right around 32 Megajoules," he said. "After that, the velocity of the projectile, the g forces involved, make the development of the projectile much more difficult, so for a variety of reasons we're looking at focusing the rail gun project more on 20 to 32."
That amount of energy would send the projectile 50 to 100 nautical miles, which Carr said would be sufficient for a long-range strike, and its velocity would still exceed Mach 7 coming out of the barrel. Until recently, however, the program had aimed for about 64 megajoules, which would send the projectile closer to 200 nautical miles.