This specification discloses an improvement in a pellet mill having a cylindrical feed receiver clamped to a radially perforated and cylindrical rotatable die. Rollers are disposed interior of the die for extruding feed through the perforated die into pellet form, the die being connected with a supporting cartridge by a ring clamp. The cartridge has an annular groove extending peripherally around a flanged portion, and an intermediate element is inserted in the groove to form a bearing and wear translative surface that engages the clamp.