I'm asking this question not so much for myself, but for my buddy who bought the Nosler book and is loading for 308 Win.
So perusing the Nosler data for 308, I noticed that the max charge for the bullet he's using (168 Gr HPBTs) was listed as 64.5 Grs of Vihtavouri N550.
I thought that was a little much, so I went to Vihtavouri's website, where their max charge for the same setup was only 47.2 Grs. That's like a whopping 17.3 Grs difference!! 
My question obviously, is how can they be so different? Is there something we're missing / not seeing?
So perusing the Nosler data for 308, I noticed that the max charge for the bullet he's using (168 Gr HPBTs) was listed as 64.5 Grs of Vihtavouri N550.
My question obviously, is how can they be so different? Is there something we're missing / not seeing?