[kosciusko51]

Yes, and I wouldn’t be surprised if Popular Science screwed up the article, or at least dumbed down the technical details.

[philman_36]

Then how about this...Hyper Velocity Projectile Range. From the BAE product brochure (2), here are some projected ranges from various weapons.
Mk 45 40+ nm
AGS 70 nm
155 mm Tube Artillery 43 nm
EM Railgun 100 nm

[philman_36]

Or how about from the Congressional Research Service, page 11...Navy Lasers, Railgun, and Gun-Launched Guided Projectile:
Background and Issues for CongressThe two industry-built prototypes are designed to fire projectiles at energy levels of 20 to 32 megajoules, 34 which is enough to propel a projectile 50 to 100 nautical miles.35