Pressure test data for a .375 Hawk from Z-hat CD(.375-06 improved or .375 Gibbs) shows 3450 fps. is absolute max with 300 gr. Only slightly slower than a .375 H&H. It is about like the .30 Gibbs just equals a factory .300 H&H. Try a .375 Hawk with a 250 gr.; it is a great elk killer. Also a 235 at 2850 fps.in my gun.