257 WBY Brass

[sniperjwt]

Has anyone herd of useing 264 win mag brass for their 257 wby. I heard about this the other day and was not sure that I herd right. If I did hear right then please explain what all is involved in doing this . Thanks for yoir help.

 

[Long Time Long Ranger]

The 7mm rem mag, 264 win mag and several others are all about the same and can be used for the 257, 270 and 7mm wby's. They are all just a little short though but after a couple firings they are the same length. The 257 wby stretches brass fairly quickly.

 

[sniperjwt]

I guess I herd right. Is there anything special that has to be done or just resize, load and shoot?

 

[Long Time Long Ranger]

If the headspace is good on the belt just run it through the 257 wby die and shoot. Screw the die down all the way to be sure it sizes completely then fireform and neck size after that. In a couple firings the brass will stretch to the wby length.

 

[kraky]

FWIW---it usually goes best with virgin brass. I notice a quite a difference on getting the headspace on the shoulders consistant even after one firing of the parent cartridge.

 

[sambo3006]

I agree with using new brass. I recently ran 100 new Winchester 7mm mag cases lubed with Imperial Sizing Wax through my 257 Wby FL sizing die and they came out looking just like 257 Wby, complete with the double radius shoulder. Sizing effort was not much greater than normal. I would hate to try it with work hardened brass however. That might result in a stuck case. The neck is a little short but doesn't seem to create any issues with firing.