7 Rem Mag-.257 Weatherby

[54bore]

Anyone do this? I read something about slight differences at the base? I ran a 7MM Rem Mag Case through my .257 Weatherby die just to see, worked flawlessly. I wish now that i had measured and noted the differences, i dont own either rifle anymore, but stil curios about this.

[Mk42gunner]

While I haven't done that particular conversion, I see no reason it won't work since both cartridges were based on the .300 H&H originally. The Weatherby case may be specced a few thousandths longer.

Robert

[GooseGestapo]

I've done it. They work.

Only two "issues"
1. Formed cases have a slightly shorter neck. Not a significant issue.
2. Case capacity internally is lower than the Norma/Weatherby brass. Start 15% below recommend charges. Most loads will be 3-5gr below regular charges.

Not a bad idea to anneal the necks before reforming. I didn't but did collapse a couple.