[He definitely has the freedom of movement to do that. Given how she grabbed him, she's kind of mostly laying across his legs. She looks at the bandolier, and then at the rifle, and nods.]

Like a crossbow, but using something other than tension to move the...bullet?

[The trigger mechanism even looks like crossbows and ballistae she's seen.]

Not really the point. I'm getting distracted, sorry. What plane do you hail from, and what exactly are you trying to do here?