So, I did this today: went into the sandbox -gasp- and tried to get numbers!
Remember, these are based off the health of the target dummies, and I compared three guns: Typhon Heavy Flak, Lumberjack Mortar, Hellhound Heavy Carronade. I used both regular shot and charged rounds respectfully
Typhon Heavy Flak
Shots to destroy Armour: 6 (5 charged)
Shots to kill ship (after armour is down:) 2 (1 charged)
Total to kill ship: 8 (6 charged)
Lumberjack Mortar
Shots to destroy armour: 7 (5 charged)
Shots to kill ship (after armour is down:) 8 (6 charged)
Total to kill ship: 15 (11 charged)
Hellhound HEavy Carronade
Shots to destroy armour: 5 (4 charged)
Shots to kill ship (after armour is down:) 6 (5 charged)
Total to kill ship: 11 (9 charged)
Time requires a stopwatch...that's why I made a video, but I need to make a better one..
It comes down to distance, fire rate, and reload speed
Reload speed alone would mean, for the expending of the clips
Typhoon Flak: 20.4 seconds (15.3 charged)
Lumberjack: 20 seconds (17.6 charged)
Hellhound: 23.1 seconds (18.9 charged)
The above time numbers do not include rate-of-fire, but the amount alone it takes to reload the clips alone.
Someone else can figure out those numbers...I'm mathing wrong.