A compression molded preform for forming an invertible base hot-fill container, and systems and methods thereof. The preform includes a body with a first open end, a second closed end or end cap of hemispherical shape, and a sidewall extending between the first end and the second end. At least a portion of the second end is thinner than any portion of the sidewall. Further, the second end is gateless and has an inner surface that is substantially smooth along its entire area. The compression molded preform is blow molded to form a plastic container with an invertible or movable base. The invertible or movable base is responsive to, or can be moved based on, internal forces or pressure associated with processing the container with a filled product.