Considering that the rail gun projectile is basically a hunk of metal, $25k does seem really expensive. No gunpowder, nothing. All the work is in the railgun.
The projectile is a marvel of materials engineering. It has to accelerate to Mach 7 in a few feet, survive friction with the surrounding air for 100 miles, and have enough remaining core to deliver sufficient kinetic energy to be worthwhile.
Its definitely not just a chunk of barstock milled to a point.
This is the more interesting question to me, not "is it cheap in comparison to what it's targeting or the alternatives" but "is it cheap based on the cost of production".
25k for a hunk of metal does seem like a very strange price, perhaps there's something more exotic to it than meets the eye?
Its definitely not just a chunk of barstock milled to a point.