Credit to Johnsonn98 on Reddit for this breakdown. I’m posting this here for posterity and so I can easily open it via Guides
 
 

Regarding ‘S’ Weapons

Pulse: Low dps, best cooling, Anti-Fighter weapon or allround weapon when in great numbers (Nemesis + Dragon)
 
 
Bolts: Allround weapon, medium dps + cooling, useful against almost anything
 
 
Beams: Anti-Fighter weapon, hitscan accuracy, but bad cooling, only useful in lower numbers (frigates, fighters and gunboats)
 
 
Plasma: Anti-capital weapon, great range, high dps, but bad cooling, useful in low numbers
 
 
Shards: Allround weapon with Plasma level dps, better cooling, but short ranged and inaccurate
 
 
Burst rays: Short ranged, low dps, hitscan, but can penetrate shields with dps bonus. Anti-Module weapon
 
 
Mortar: Comparable to Plasma, but with Flak-esque aoe damage and higher projectile speed. Currently stronger in IS combat due to double damage mechanic
 
 
Mass drivers: Railgun, long range support weapon. Lowish dps and cooling problems
 
 
Thermal Desintergrators: Pulse-Laser-styled weapon but with shield penetration and dot effect. Very effective weapon, M sized variant very inaccurate though
 
 
Split Minigun: Bolts but with higher dps and inaccurate, useful against bigger targets, but Shards and Tau’s are better suited for that. Underperforming imo
 
 
Tau Accelerators: Shards but with more dps and higher accuracy. Very effective allround weapon
 
 
Boson Lances: Mass drivers with way higher damage but with less range and even more cooling problems. Still testing around, but seems too unreliable. Strongest OOS weapon though
 
 
 

Regarding ‘M’ Weapons

Pulse: Anti-Fighter turret with highest rotation speed but low dps
 
 
Bolts: Higher damage than Pulse with slower rotation speed
 
 
Shards: Higher damage than Bolts but short ranged and inaccurate. Useful against M+ sized ships but so is Plasma
 
 
Plasma: Insane dps for its size (L Pulse level), useful against M and above sized ships. Outperforms their fixed gimballed version due to lack of cooling problems
 
 
Flak: Anti-Fighter – Allround turret. Somewhat short ranged but with aoe explosion effect and thus with higher dps than shards (~140 ARG, ~210 SPL). Very useful turrets if you have access to them
 
 
Beams: Don’t bother, they can’t kill space flies
 
 
 

Regarding ‘L’ Weapons

Pulse: Allround turret, useful against anything. Struggles with XL shield regeneration in low numbers though
 
 
Plasma: 3x Pulse’s dps, Siege and Anti-capital turret. May sometimes struggle hitting moving targets (even large ones), but most potent against impaired targets
 
 
Beams: Very dissappointing turret. Hitscan makes them effective against fighters but their dps is comparable to 1 M sized Pulse Lasers. Never use them against anything M+ sized targets. L+ targets don’t even get damaged by them and Pulse is way more effective against M sized ships.
 
 

 
 
Hope you enjoy the post for X4: Foundations Weapons/Turrets Comparison, If you think we should update the post or something is wrong please let us know via comment and we will fix it how fast as possible! Thank you and have a great day!