The [DMG] modifier is a little more intricate than a flat +5 bonus damage per volley

A blue {Ship Weapon} Mk (N) [Dmg]x2 = A White {Ship Weapon} Mk (N+1)

So:

Antiproton Dual Heavy Cannons Mk __X__ [Dmg]x2 = Antiproton Dual Heavy Cannons Mk __XI__

Disruptor Beam Array Mk __VIII__ [Dmg]x2 = Disruptor Beam Array Mk __IX__

Tricobalt Torpedo Launcher Mk __XI__ [Dmg]x2 = Tricobalt Torpedo Launcher Mk __XII__

And so on...at least according to my research and simple arithmetic. Furthermore, I thought I should add this to deepen an informed discussion, rather than pick one side or the other

The Spice Must Flow...