Yes that BAE Systems test fire.
Mostly though, railguns are not practical to use right now (in reality). This is because the great amount of heat produced and the great amount of energy that is needed to power it. The heat produced is enough to melt the metal rails (believe made out of copper), making it an extremely expensive one-use weapon, more so than a cruise missile. Now I have heard that they have been able to design railguns now that are not 1-use weapons, but they don't fire the round as fast or as far as the rounds fired from the 1-use weapons.
I wonder if they could take a concept from a tokamak and apply it to the inner workings of a railgun (in that, the inner core of a tokamak is so hot that its amazing that it doesn't melt everything from within; though it might not work as the railgun uses a magnetic field to do the acceleration and the tokamak uses magnetic fields to induce a nuclear fusion reaction)... also the power required for it to be used is roughly the equivalent of a small nuclear fission reactor... you know the ones they put on ships and nuclear submarines... not very practical for a tank, but works fine for a ship.
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Well.. that is unless the tank is of a landcruizer size of course, then it works... otherwise no.
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