I was at the range yesterday doing some prep work for a date with a Cape Buffalo.
As usual, I had the chronograph set up and shot many of my rounds over the screens for "science".
Several recent discussions re: primers here had me load up a few loads in 450/400 and 450 Dakota with everything identical except the primer, just for fun.
Now, a 15 round study doesn't qualify as a statistically valid sample...but it's a start! So, from the FWIW department, I submit the following:
1. 450/400 NE with 86gr H1000 and a 400gr DGS in Hornady brass:
Fed 215 = 2018fps
Tula Mag = 1966fps
2. 450 Dakota with 88gr IMR 4064 and a 450gr TSX in Dakota brass:
Fed 215 = 2299fps
CCI 250 = 2275fps
Tula Mag = 2267fps