Magnum primers make lots of sense in the 375H&H. Some of the posters mention that it is a large case but not overbore by any means. Whilst this might be true, standard H&H loads vary between 75 - 80 grains of powder. I think thats a lot of powder, especially in a long column. Magnum will guarantee you a result, whilst standard primers may hangfire under less than ideal conditions. Not great for what is essentially a hunting cartridge, often used on dangerous game. Just my 2c worth guys.