OOC: There is probably a control room, but you have no idea of how this thing work, how large it is, where the control room is and such stuff! And for backdoors, you've found one door, wich you've already revealed, you don't know anything else.
Eric: The first shot hits and disables a joint in the arm, the second shot misses as the arm does an akward movement.
Mithran: You follow the marine to the armory, all gear at the ready then mounts the jeep and starts it up, silenced engines engaged.
Jake: Jake fires his PCR in a three round burst at the arm. All three bullets hit one of the coil's arms, cancelling the load-up for a second.