This achievement is obtainable in any gamemode with starfighters, but you'll want to be playing Starfighter Assault for this for reasons I'll explain. There are six maps in Starfighter Assault and only 4 of them allow you to play as the bomber ship, so you'll want to avoid playing on D'Qar and the Unknown Regions.
In every match of Starfighter Assault, there will occasionally be Ai bombers that will target the objective. When playing as the attacking team your objective is to escort them to the target. When playing as the defending team your objective is to destroy the bombers and enemy starfighters.
This achievement is very easy when on the defending team because destroying the Ai bombers actually counts for the achievement. Its easier still because they always fly in a straight path to the objective, don't target players at all, and always spawn in groups of three. They do have a lot of health so you'll want to get them to roughly half health with your laser cannons and then use your dual torpedoes to finish them off. Positioning your craft right behind them so your torpedoes can have a straight shot also helps. In my experience trying to lock on with the torpedoes from a distance is a pain, sometimes they just veer off course randomly? Star Cards can be used to make this slightly easier, specifically Advanced Torpedoes, which just increases damage, and Advanced Target Lock, which makes gaining a missile lock easier. Reinforced Hull can serve as a good safety net, as there will be enemy players trying to prevent you from destroying the bombers.
This is not a quick achievement. Several matches of Starfighter Assault will be required to get all the dual proton torpedo kills. My advice would be to always go for the enemy bombers when on the defending team, but also to just play a lot of Starfighter Assault as the bomber. It isn't easy, but you can gain significant progress by just dogfighting and killing enemy players with the torpedoes. The torpedoes are very slow so trying to hit fighters or interceptors is challenging, but when you do its almost certainly a one shot kill due to their damage bonus and the faster ships having less health.