Re: 300 WM
It's a good question, and Driftwood is correct.
Note that the Sierra manual lists 75.4 grains of H1000 as a maximum load.
Since you are using Sierra bullets, maybe you should give them (Sierra) a call and ask about it?
Incidentally, the Hodgdon manual also says: "This data, as the data in any reloading manual, is not absolute. It should only be used as a guide for working up your best load......."
Each rifle is unique and as the previous response says, you should gradually work up the load for a rifle.
Never just grab a maximum load out of a chart and assume it is safe.
Start lower, and work up gradually, while watching carefully for indications of excessive pressure.