An injection-molding device for producing a hollow-formed plastic object, at least comprising a mold for the primary shaping of the plastic object, an injection device for at least partially introducing a flowable polymer melt into a cavity within the mold and a fluid injection device for introducing a pressurized fluid and for driving a projectile through the polymer melt introduced into the cavity, the mold comprising a mold wall and a mold core that is arranged at least partially within the mold wall, the projectile being formed at least partially in such a hollow-formed manner that it is arranged on the mold core and is movable along a longitudinal extent of the mold core on the latter. A projectile injection process for producing a hollow-formed plastic object with this injection-molding device and a hollow-formed plastic object produced by this process.