For various reasons times have changed in relation to recommended max loads over the years.
I have a Lyman 45th edition handbook here, copyright 1970, It lists,

158g Cast bullet /w gas check
Starting load of Unique 4.0g = 680fps
Max Load of Unique 8.0g = 1250fps

You should start at 10% below Max (7.2g) and work your way up watching for pressure signs. Use Caution.
Sal