5278? Out of a 27" bbl....maybe, just a little hard to believe...only 2gr. difference than the .220 Swift load at 5046fps
.....that sounds high as well....but without a chronograph and the exact pickings, how can I dispute it? The original factory load for the .220 Swift were advertised at 4100, and that was with a 32gr as well, as far as memory recollects...but as far as commercial cartridges go, looks like the .204 Ruger tops the list....at 4225.