Home Forums Reloading Big Game Rifles WHAT POWDER TO USE IN 257 ROBERTS WITH 117GR BULLETS

HI EVERYBODY i recently traded for a ruger ultra light in 257 roberts with 20 inch barrel i was wondering what powder seems to bring out the best acuracy with the 117gr bullets in this caliber thankyou for your help deershed.

I use H4831SC and H4350 with bullets from 110g to 120g in my Ruger. (Not an ultra light.) Excellent accuracy and velocity.

You could do a lot worse then H4831 with 117g in a 257 Rbts. My most accurate load in a Roberts is with 117g and H4831. Other powder that work good (just not as good) have been H4350, and H414

See attachment. Those are one inch squares and that is five at 100 yrds.

Load was and still is

117g Sierra SpBt
43g H4831
Rem case FL sized
Case Length 2.225 trimed
Rem 9 1/2 primer
C.O.L. 2.850 inches

H4350
RL19
Ramshot Hunter
N560

In no particular order.

Try 44-48gr RL19.It's very consistently accurate and will give as high or higher velocities than others.

I always got top velocities and superb accuracy in my Roberts using Reloder 22. Eagleye.

I've had teh best results with Re19, Re22, H4350, in that order...

My powder of choice was IMR 4350 with the 117 grain Sierra boat tail. I tried a load with 35.0 grains of IMR 4064 and this load groups well. I haven't run it across the chrono so I don't know what velocity it is getting. It might be possible with the shorter barrel, you would get a more complete burn with the quicker powders. 4064 is quicker burning than 4350.