Rail guns are that fast with incredible accuracy.
That’s right. I think a couple of our ships have rail guns which are being tested at sea. I haven’t kept up on it and you probably know.
A railgun might well be incredibly accurate, but it is fired with a pre-determined destination of where a target will be if it is moving, or against a non-moving target.
There is no terminal guidance on a rail-fired weapon that I am aware of. If you fire it against a non-moving target, it can hit. If you fire it against a moving target and calculate where that moving target is going to be and it doesn’t change course or speed, it will hit. But if it moves erratically, I don’t see how they are going to get around that.
Like this whole thing with hypersonic torpedoes. Sure, it can go fast underwater, and if you fire it close enough that evasive action isn’t possible it could get a hit. But any distance away, you are going to get course and direction of the inbound torpedo and even a small change in your course is going to cause a miss. Take the difficulty in terminal guidance in the air and it is multiplied many times over in a liquid environment.
Hypersonic stand off weapons against stationary targets are going to be the way to go...you can engage from further away (grunts on the ground need air support) so you don’t have to fly close, and the range will be closed far quicker by the munition.
But against moving targets? I don’t see it.
The dart projectile developed for the rail-gun can be incorporated as a sabot round fired by a powder gun to achieve about one-half (50 NM) the electric driven range. The Mk 45 Mod 4 (5-inch gun) can fire up to 20 rounds per minute. Some of those rounds are outfitted with guidance and a proximity bursting charge to provide a fragmentation intercept.