A post of mine from the facebook group from 2021:
I got to watch the latest season of The Expanse the other day, because the previous occupant of our holiday flat didn't log out of Amazon. It got me thinking, in 2300AD terms what sort of ship is the Roccinate?
Scaling of Expanse ships matches 2k3 pretty well, with PDC numbers being in the same range as 2k3 turrets. Expanse battleships have 40-60 PDC's (the Donnager class having the most at 59), whilst torpedo boats and patrol ships have 2. The Roccinate has 6 PDC's, which would equate to 6 lasers.
The number of torpedoes on Expanse ships is a little nebulous. The Roccinate has magazine space for 20, and can fire a pair at once from a side mounted single launcher, of whch she has two (4 torps per max. salvo on screen). The "heavy frigate" has 40. When Donnager took on the stealth ships, she launched 20 torpedoes at them from her 6 very large launchers. The stealth ships fired 2 torpedoes each in every encounter.
The converted belter ships fired many more torpedoes, but it should be noted they weren't Epstein drive torpedoes (cf the yellow rather than blue [exhausts]) and so have far less capability. In the attack on the Ring gate you can see the CL Pella fire ca. 12 blue drive torpedoes, and other ships firing salvoes of yellow drive torpedoes (4, 9, 8, 10, 10 and 8 onscreen) within railgun range. These > 61 torps (since some salvoes aren't seen) were defeated by the BB PDC's. Medina station fired 6 blue drive torpedoes into the Martian BB, killing her. The Laconian torps are difficult to separate, but it looks like the Barkeith (a Donnager) fired 10 blue drive torps at each of the remaining BB's.
In the Zmeya fight, the Zmeya has 24 torpedoes in her forward bay (in six quad packs), and fires 23 yellow drive missiles at the Roccinate, and a blue drive "stealth torpedo" with the protomolecule away from the fight. Drummers ships had 8 torps (Tynan), 17 torps (DeWalt) and an unknown no. (Mowteng, 23 can be counted on the hull of the concept art and she likely had ca. 30-35). All simply strapped torpedoes outside of the hull.
Missiles thus seem to be more common in the Expanse than 2k3.
The other weapons system, railguns, could perhaps be represented by the large lasers the Kafers and a few Terran ships (Piedrabuena) have. This would be especially true if you use house rules that allow large arrays to focus further.
Anyway with 6 laser turrets, and a pair of missile launchers fed by a significant magazine, the Roccinate is roughly equivalent to a Kiev type destroyer in 2k3. No wonder it was missed.
