If you are serious about weapon design, you may prefer to use Ennead Games's Starship Kit 4: Weapon Generator (also available here) but if you just want to be able to talk convincingly about a ship's armament then this product will do fine and be far faster...
Based on the same tables as in the generator, all you need to do is roll a percentage and there you have a weapon described in the sort of detail your average spacehound would use if asked. Or, of course, you can just pick something that sounds right for your purposes.
Do you want to mess with a ship armed with a Mark VI Pulsing Anti-proton Bomb?
Naturally, if matters turn nasty, you will have to determine just what a Mark VI Pulsing Anti-proton Bomb does under the ruleset you are using for your game, but providing you are comfortable with your chosen game mechanics that should not be too hard.