Coverplates are disposed to axially overlie end faces of the shanks of buckets and the dovetail connections of the buckets within turbine wheel slots. The coverplates have axially projecting angel wing seals. The coverplates also have balance weights on axial faces thereof opposite the angel wing seals to balance out any bending moments applied to the coverplate resulting from centrifugal forces when the turbine rotor is at speed. Thus, the centers of gravity of the coverplates are located close to or in the plane of the coverplates. A centering slot is provided along an inner face of each dovetail connection for the coverplates. Coverplate retention pins reside in wide sub-slots at the bases of the wheel slots. When the coverplates are secured against axial movement, the retention pins engage in the centering slots of the coverplate dovetails to prevent circumferential movement of the retention pins in the wide sub-slots.