Hi deniz82:

There is no R slot torpedo u mentioned. Torpedos from SS can only be fired from T Slot.

Almost all SS2 onwards has Guns mounted on the ship, you cant remove it. But u can choose to put gunner on it to use. 

The most popular of using Gun on SS is the KM SS4 Type U - Flak I cuz it has 3 machine R guns and the reload is nice.