Abstract: In a nuclear reactor fuel bundle packaging apparatus including a hollow cylindrical cask (22) and a basket liner assembly (23) receivable within the cask, the basket liner assembly including a plurality of laterally spaced disks (26) rigidly held by a plurality of tie rods (28), and a plurality of elongated hollow basket liners (33) extending through and fixed to the plurality of disks, each hollow basket liner (33) holding a nuclear fuel bundle assembly (10) having an upper tie plate (14), a lower tie plate (16) and a plurality of fuel rods (12) arranged in a substantially square array, extending between the upper and lower tie plates, the improvement comprising an oversized hollow fuel bundle channel (68) received over the fuel bundle assembly, the channel (68) having the same cross sectional shape as the basket liner (33) but sized to fit within the basket liner, the basket liner having at least one slot (74) formed in at least one side thereof at each disk, and at least one spring (72) mounted on the bask