Is the stock on a 12 gauge Winchester 1897 the same size as a 16 gauge 1897 Winchester?

No, the stock of a 12 gauge Winchester 1897 is not the same size as that of a 16 gauge model. While both models share a similar design, the dimensions and proportions of the stocks differ to accommodate the varying sizes and weights of the different gauges. Specifically, the 12 gauge stock is typically larger and heavier than that of the 16 gauge.