Designed to minimize operator attention and simplify loading, the case magazine system on A-B-C erectors features a low-level, high capacity design. The magazine has a built-in auxiliary magazine which holds three hundred cases and assures a continuous supply of cases to the erector. As each stack is depleted an automatic case stack indexing mechanism feeds the next stack into position, minimizing the attention of the line attendant. To refill the magazine, the attendant simply slides case stacks from the pallet to the auxiliary magazine at any time during operation. The standard unit has a capacity of three stacks while extensions are available for packagers who require additional capacity.