A baler having a frame, a feed system coupled to the frame, and a compression assembly in operable communication with the feed system. Where the compression assembly includes a baling chamber, a gearbox having an output shaft, and a crank arm defining a first mounting point and a second mounting point spaced a distance from the first mounting point, where the first mounting point of the crank arm is coupled to and rotatable with the output shaft of the gearbox. The compression assembly also includes a plunger positioned within and reciprocally movable with respect to the baling chamber, where the plunger defines a third mounting point thereon, and where the distance between the second mounting point and the third mounting point is variable during a baling process.