Welcome to Hypervelocity, Armour Piercing, High-Density Munitions 101. One of these, mounted as a railgun, and loaded with a volley of the above mention ammunition could be an effective system. Essex, you should ask Iyecte if you can use his superconductor technology rigged to an accumulator. Then you can just railgun pretty much anything. I don't think conventional armour would be able to stand up to such a system. Dang, I should put these on my airship! Deployable shields and flat-trajectory projectile broadsides! Boo-yah!

Is that based off of the Mk45 naval gun at all? If so, great job emulating it! (No sarcasm!)