If you are shooting a .375 H&H I would suggest you do some research before you start looking to faster powders for higher velocities. The information I have reviewed suggests that especially in the large magnum calibers the slower powders will actually produce the higher velocities. The shorter barrel does not change this situation. I have a Remington 788 in .243 with a 18 1/2 " barrel. I have tested a lot of different powders suggested for the .243, from the fastest to the slowest, and the slower powders have produced the higher velocities. H4350 produced not only the greater velocities but grouped them better also.