"magic" sword

so I've got a request to make a "magic sword that launches some kinda projectile to represent a magic attack." so i started designing something for larping and airsoft of course. you'll need two brass tubes the length of your intended sword blade with 0.375" (9.525mm) OD and 0.315" (8.001mm) ID. at least for my version. on of these tubes will be capped with a spring inside and the other is left open at the blade tip. i settled on one of the chinese straight sword designs that had a flat double edged blade instead of the diamond cross section because it gave me more room for the tubes and was easy to mirror for a first attempt. you will also need pan head M3 screws, a spring that fits inside the tube (i found some 7mm x 600mm for mine), a mechanical pencil spring for the trigger mechanism (or stiffer substitute), and finaly some stiff silicone for the core (probably shoreA 40-80) with softer silicone for the edge (probably shoreA 10-40). because of the limited space in the BB loading ar