Bricktop, you have likely done more testing with the 257 Bob than many on here, if given a choice of all the powders that work for it, which one would be your choice when using a 117 grain bullet?
It would have to be that RL-19, without a doubt. It was the top powder I used with my No. 1 in .257 Roberts and it's provided the top velocities in this rifle, too. The 4350s would be a close second.
