51g H-4831 produced 3085fps with a standard deviation of 10. Very accurate load, under .5" at 100, shot 3 shot groups at 525 that gave 3-4" groups consistently. Winchester model 70 classic sporter 24" barrel.
Finally got to shoot some today, nothing too exciting but as I neared Max
of 60 and 60.5 grains some of the bullet holes started touching.
I will have to load some more near max and see what happens. Velocity
at 60 grains was 3068 fps for my 25-270. Velocity at 55 grains was
2700 fps with 3 shot group of 1.2" at 106 yards.
I too have been using Retumbo with the 110 grain AB. My groups were best when I was at 60 grains as well. As I suspected, it appears that retumbo may be a little bit too slow burning for the 110 grain bullet based on those velocities. Looks like I will have to give H-1000 a try.