FWIW, they do shoot a tighter group if you slow them down to 2350fps, which is still a potent load.
I just remembered. 42gr Lil Gun, Rem 7-1/2 Primers, 2.08 COL Taper Crimp to .474, which despite being a little heavy handed for a non-cannelured bullet, seems to have gotten you better velocity than I got with .476 and my 20" barrel back in July of 2010 (before I got adventurous) . Interesting...
In Theory, there is no difference between theory and practice. In Practice, there is.