300 H&H brass to 257 Weatherby

[Mac11700]

Hello All:

Here's a question for all of you guys who might have an answer for this...is it possible to convert 300 Holland & Holland magnum brass over to that of the 257 Weatherby???This is the parent cartridge for it,and since 300 Holland brass is a whole lot cheaper to attain...is this a possability...if so what steps are involded and what dies would I need other than a full lenght 257 Weatherby die set...and has anyone else every tried this???


Thanks for your input

Mac

[yooper77]

I have a C&H forming die for making 300 H&H magnum brass into 257 Weatherby magnum brass.  I have also slowing forming 300 Winchester magnum brass into 257 Weatherby magnum.  After forming I trim the case to length before I size in my 257 Weatherby magnum full length sizing die.    I have also made 257 Weatherby magnum from 7mm Remington Magnum brass, but it is .060” too short.  All this brass also needs the neck thickness check and trimmed, along with safely working up reloads.

yooper77

[Graybeard]

That's the ONLY way they had to do it back when the originals came out. So yeah it's possible but probably not worth the hassle when properly head stamped cases are currently available.

[sdb777]

It does save some cash with Weatherby head stamped going for almost $30/20 rounds, and 300WM brass going as low as $13/20 rounds....but you would have to do a lot of brass to get the benefits from purchasing the equipment to do the conversion.


Scott (prices won't go down now) B