gyro-pigeon

from The Century Dictionary.

• noun A contrivance of tin having flanges so arranged spirally that when a rotary motion is imparted to it its gyrations cause it to rise in the air: formerly used as a target for shooting.

from the GNU version of the Collaborative International Dictionary of English.

• noun A flying object simulating a pigeon in flight, when projected from a spring trap. It is used as a flying target in shooting matches.