Abstract: A heavy duty rotary concrete mixing drum (16) for coupling to a vehicle (10) having a powered drivetrain (18) for rotating the drum comprises a wall and at least one projection (32). The wall (33) includes an inner surface (34) defining a volume and an outer surface (36). The at least one projection is coupled to the wall and extends from the inner surface of the wall. The projection includes a body and a support member (48) disposed within the body.