actually they use a xbox controller as the soldiers said that they are familiar with where the buttons are ect. they use it for spy rocots with camara's on them.
That's a blank firing attachment or BFA and you need it firing blank ammo so it sends gas pressure to accuate the bolt so your rifle isn't a single shot, Im a gun nerd...
And easy to manipulate what each button does (crazy computer/circuit board programming stuff that i don't understand) and the soldiers are familiar with the controler, comfortable in their hands, etc...
Why not? wouldn't you rather have a controller you are familiar with instead of some uber complicated array which would take weeks of training to master?