I wouldn't be surprised if it's not a separate class of turret, just renamed and guaranteed longer range, 99.5% accuracy, high fire rate, and independent targeting. I would say low damage too, but I've seen some that have better DPS per slot size than almost all the regular chainguns I've found. They're almost too good as regular weapons with that bonus range+accuracy, perhaps some damage should be replaced with a bonus vs torpedoes and fighters.