Aluminum turbine slugs out of a shotgun are a pretty interesting concept. This custom-made turbine slug is quite a work of art, too.
These custom-made slugs were made on a CNC machine specifically to be launched from a shotgun. The rifling cut into the slug itself is meant to help stabilize it in flight to the target.
A variety of projectiles can be shot out of a shotgun. This all-aluminum projectile just might become another selection in the future.