The hornady version (wby factory ammo) clocked 3610 fps out of my accumark. I used RL22 to duplicate same. IMR 7828 does it too!

Haven't tried the 100 grain load, but I have no problem matching the 115 grain load with IMR 7828

The other guys are right, that factory 100 grain ammo for the .257 Weatherby Mag is FAST!

My chronograph shows just about the claimed 3600 fps from a 26 inch Weatherby rifle.

However, I was one of the guys who posted that with H 4831 or Reloder 22 either one, I just could not safely get to 3600 fps with my reloads.

Getting over 3500 fps was not a problem but as I approached the 3600 fps level the pressure signs became apparent. Hey, 3500 fps will kill anything I point it at!

R F

26" barrel and Norma MRP which is identical to RL-22. With MRP and 100gr Hornadys, not only can I match velocities, but both reloads and factory hit to the same POI. Tht is a good secondary indicator taht your loads are pretty similar I would think. jorge

Thanks a ton guys. It seems like Weatherby might not be exaggerating too much. It sure is a fast round! If paper ballistics can be trusted, a sight-in of 2" high @ 100 yds, should give you a zero of about 270 yds, 1.5" low @ 300 yds and 10" low @ 400 yds. That is flat!
- mike