rshmelzle,
Different lots of 4451 have varied a little, probably due being a new powder. I obtained two different lots the first year, and one resulted in velocities about 50 fps faster than the other lot in loads around 3000 fps. The "faster" batch was much closer to Hodgdon's published data.
Since I only had a couple of pounds of the slower-velocity lot, and eight pounds of the faster one, I eventually mixed them to have a more consistent blend--which will probably happen with new lots as they have more batches to blend.
