My 257 weatherby shoots the factory ammo with 100 gr TSX so well that it's scary. I would really like to duplicate this and reload my own. Does Norma load for Weatherby? If so, any idea about the powder that Norma uses? Thanks. Gary

quote:

Originally posted by GaryG:
My 257 weatherby shoots the factory ammo with 100 gr TSX so well that it's scary. I would really like to duplicate this and reload my own. Does Norma load for Weatherby? If so, any idea about the powder that Norma uses? Thanks. Gary

Yes Weatherby ammunition has been loaded by Norma for many years. Currently listed on the Norma website is loads for the 7mmWM and up but nothing for the 270WM or the 257WM. The 7mmWM and up use MRP powder as probably do the big cased 270WM and (overbore) 257WM. Some earlier Norma catalogues have loads for all the Weatherby cartridges. I don't have one on hand now.

I used the Norma MRP2 to load the .257 WM with Barnes TSX for a friend, worked pretty well.

While the WBY factory loads almost certainly use a Norma powder, they likely use non-cannister "grade" powders which vary a bit in burning characteristics from "cannister grade" powders. With the .257 WBY, you can probably come closest to duplicating the factory load by working up with Norma MRP (or Reloader 22 or 25, which are made in the same plant and are essentially the same as Norma MRP and MRP-2).

71.3gr Norma MRP, F215 primers will get you the exact factory load. And of course you can substitute RL-22.

Thank you everyone!

Didn't IMR 7828 used to be a popular powder for the Weatherby's?

quote:

Didn't IMR 7828 used to be a popular powder for the Weatherby's?

I found that 7828 would give velocities close to MRP. I've found the right Lott of RL22 to be ev en closer.