Waste compacting apparatus comprising a hopper; a compaction tunnel communicating with the hopper and providing an outlet for waste deposited therein; a packer located and reciprocable through successive forward and return strokes to advance waste from the hopper into and through said compaction tunnel, a ram, forming part of said packer, normally telescoped therein and retractably extendible therefrom in the direction of reciprocation of said packer, the ram having a leading end which forms a small portion of that of the packer as a whole when the ram is telescoped therein; motor means for reciprocating said packer through successive cycles of operation respectively comprising forward and return strokes, a standard cycle of operations commencing at a lead-off position with the ram telescoped in the packer and re-cycling means, responsive to mechanical stalling of the packer in the forward stroke of a standard cycle of operations, for terminating the forward stroke, returning said packer to its lead-off position, and initiating a special cycle of operations comprising forward and return strokes in which the forward stroke is effected with the ram extended.