Abstract: A classifying wheel for a centrifugal-wheel air classifier, through which the classifying air flows from outside to the inside against its centrifugal action. The wheel has blades arranged in a ring extending parallel to the axis of rotation of the wheel. The blades are positioned between a circular disc carrying the classifying wheel hub and an annular cover disc. The classifying wheel is entirely made in one piece and of a wear-resistant sintered material. The flow channels of the classifying wheel are formed by the surfaces of the classifying wheel blades extending parallel to each other and in direction of the axis of rotation of the wheel.

Abstract: An improved construction and support for a twist-reducing ring carried on a stabilized projectile is described. The ring, which is rotatably supported in an annular groove in a portion of the projectile jacket, is formed from a plurality of circumferentially abutting, axially aligned powdered metal segments. Such segments, which are released upon separation of the projectile from the surrounding cartridge case, are initially retained in place either by the front wall of the cartridge or by a separate, easily destructible auxiliary ring. The ring segments are either directly rotatably engaged with the bottom wall of the annular groove, or are housed within a separate U-shaped container which, in turn is slidably mounted in the groove.