Some old data for the 378 factory rounds had two loads, and I am just going back to the early 90's here, so maybe there were other iterations. A 300 grain at around 2900fps for about 5700fttlbs and the 270 grains at remarkable 3180fps for about 6064ftlbs....it was a bit of a difference in power and I always wondered if the second figure had some blue sky figured into by Roy.
