True. Many B's were chambered for 9 Para specifically, which is also higher pressure than Largo. Their construction reflects this. Any B originally made for .38 Super would have received the same attention. The earlier Astras and Super A's in Largo could handle .38 Auto, but it's hotter version, .38 Super, was pushing the limit, as was 9 Para, really. Although you could do so in a pinch, these pistols were never intended to fire anything but Largo, so their metallurgy reflected that.