I've had several .250 Savage rifles, but all had short barrels (2 Ruger Ultra Lights, 20", a Ruger RSI full stock, 18 1/2", and a TC Contender, 20"). I found H4895 powder to provide the best overall accuracy with bullets in the 87 - 100 grain range. About 2700 - 2750 was the best velocity I got from any of my guns using 100 grain (usually Sierra ProHunter) bullets. With the 87 or 90 grain Sierras, I could get between 2,900 and 3,000 fps. I saw slightly better velocity with powders other than H4895, but usually with a decrease in accuracy.
I have one .257 Roberts, a Kimber, purchased about ten years ago. I believe it has a 22" barrel. A maximum and accurate load of H4350 with either the Barnes 100 TSX BT or the 100 Sierra ProHunter gets about 3,100 fps muzzle velocity.
