Fang QS-4 nerf blaster barrel replacement

Replacement barrels for the Fang QS-4 nerf blaster. This allows for compatibility with half length and solid core darts. It also improves performance when combined with a spring replacement.

The interface stubs slip in between the barrels and the manifold. The air restrictors must be retained in order for the manifold to work. Do not use a raft when printing, as the bottom of the barrel model must be smooth in order to form a good seal with the air restrictors.