Gas spring piston with partial bellows support feature and gas spring assembly including same

A piston for use in forming a gas spring assembly includes a longitudinally extending axis, a first end wall extending approximately transverse to the axis, and an outer side wall extending longitudinally from adjacent the first end wall. The outer side wall includes a first side wall portion that forms a fully circumferential outer surface and a second side wall portion that forms a partially circumferential outer surface that extends longitudinally beyond the fully circumferential outer surface. A gas spring assembly including such a piston is also included.