Here is some data I worked up in a 336 Marlin;
Federal Cases, Rem 9 1/2 primers,
Lee 170gn FN GC cast from WW, water quenched, 50/50 Alox lube.
Sized 0.311
This is Hercules (old) 2400. 5 shot groups 70 Degrees
16.5gr 1832fps 3" @100
17.0gr 1850fps 2.4"@100
17.5gr 1900fps 2.75"@100
18.0gr 1953fps 6.0"@100
I am currently loading 15.4gr 2400 and am getting 2.5" groups, I haven't
chronographed the load yet, but I'm happy with the results.