Heavily armored and very powerful, the gun turret can cause many problems for lower level and lesser geared players. Each turret fires twice for each of their turns and do a substantial amount of laser damage if the player is not armored. Their small health pool makes up for this, somewhat.
Generally you want to avoid getting in their fire zone by using a long ranged weapon to draw the bipedal enemies surrounding them, and then take them out.
Alternatively, if you lack a weapon with that amount of range, take out the turret first or try and pull the surrounding fores (If their are any.) away from the turret.
The following is based on Fallout Tactics and some details might contradict canon.
In Fallout Tactics, gun turrets can be found guarding the second generator during the Jefferson mission and in the building Albert Lamore is hiding in during the Newton mission.
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