I here present a Rivals ammo 57-minute print launcher almost fully 3D printable, just needing a common steel spring sith 6.15 mm of diameter and 30 - 35 mm length fully extended. For it to print in that time, no supports should be added, 0.32 mm layer height should be set (the max for a 0.40 mm nozzle), 60 mm/s speed should be set and 3 to 4 walls should be added to ensure enough force for the print to shoot properly. The axis that creates a joint between the lever and the main body pieces can be a simple piece of cut filament (1.75 mm filament).
The author hasn't provided the model origin yet.