I literally just did this for my last game (and plan on putting the mission in the toolbox here once the mission and podcast of it are done).
Basically just took one of the current drones, added in the drone programs needed, slapped on two colt m23s (it was an individual's home-made drone, not some megacorporation with the ¥ to spare for hmgs and what not), changed it's speed and accel, increased it's pilot. Then 1st phase it actively targets (while saying "halt") and then 2nd phase full auto. Rinse and repeat as needed. Great to see the look on the players' faces the first time in the campaign I say, "it's firing a full auto burst," hehe.