weatherby 257 brass
- Thread starter sanddude
- Start date
I make 257 Weatherby brass out of 7 Mag brass or 264 Win mag brass, just neck it down after lubing it with lee sizing lube. The neck is just a little bit short, does not mean a thing.
I shoot the 100g with 71.5g of R#22 with a Fed 215 primer in a Win Case that has been necked down from 7 Mag...really tough brass compared to Weatherby (norma) brass.
good luck!
I shoot the 100g with 71.5g of R#22 with a Fed 215 primer in a Win Case that has been necked down from 7 Mag...really tough brass compared to Weatherby (norma) brass.
good luck!
Last edited:
bubbabassin45
New member
I also use 7mm mag brass necked down for my 257 weatherby. Works fine for me.
You guys are shooting std 7mm & 264 mag brass in your Weatherby chambers without any problems? Does it fireform the normal mag case to Weatherby? Wondering about the length and double radius of the shoulder. 25 degree shoulder of the 7 mag to the 35 or so in the Weatherby.
1shotshooter
New member
I order mine from this place. They will pick it out of the same lot if you ask them to.
http://www.midsouthshooterssupply.com/de...%59%20%4D%41%47
http://www.midsouthshooterssupply.com/de...%59%20%4D%41%47
Forming 257 Weatherby, 270 Weatherby, and 7mm Weatherby brass from 7 Mag brass is as easy as it gets.
I use the Lee Sizing wax on the neck and shoulder. After lubing the NEW WINCHESTER 7 Mag brass, I just run the case into the 257 Full length sizer. What is really amzazing is that the shoulder is perfectly formed on the Weatherby brass! The neck will be a little shorter on the 7 Mag re-formed brass.
I had a custom reamer made for a 257 Weatherby with the shorter necks. I sent Pacific PRecision three new unfired Winchester cases that had been formed to 257 Weatherby, and had him build a MInimum spec, zero freebore reamer to fit the Winchester brass.
In a 26" Pac Nor barrel, 71.5g of R#22 shot 3/8" groups with a 100g Nosler Ballistic tips at 3800 fps. I have fired the cases 5 times before I start to loose one or two from the primer pockets opening up. No doubt that the 257 Weatherby with Zero freebore is one of the finest long range rifles that I have ever owned.
It is very important that you use NEW Winchester brass because the fired brass has work hardened even after one firing. Remington and Federal brass are junk in this application because their Rockwell hardness is much less than Winchester.
I also shot the 115's at 3650 Using R#22, Fed 215 Primer.
If you try this experiment, then work up to these loads on your rifle. I would only use a modern bolt action rifle, because I have no idea what the pressures are in this round. I do know of 6 of the 257 WEatherby's that are shooting the 100's at 3800-3850 fps with amazing accuracy and one 30" Hart barrel that is shooting the 100's at 4000 fps.
I use the Lee Sizing wax on the neck and shoulder. After lubing the NEW WINCHESTER 7 Mag brass, I just run the case into the 257 Full length sizer. What is really amzazing is that the shoulder is perfectly formed on the Weatherby brass! The neck will be a little shorter on the 7 Mag re-formed brass.
I had a custom reamer made for a 257 Weatherby with the shorter necks. I sent Pacific PRecision three new unfired Winchester cases that had been formed to 257 Weatherby, and had him build a MInimum spec, zero freebore reamer to fit the Winchester brass.
In a 26" Pac Nor barrel, 71.5g of R#22 shot 3/8" groups with a 100g Nosler Ballistic tips at 3800 fps. I have fired the cases 5 times before I start to loose one or two from the primer pockets opening up. No doubt that the 257 Weatherby with Zero freebore is one of the finest long range rifles that I have ever owned.
It is very important that you use NEW Winchester brass because the fired brass has work hardened even after one firing. Remington and Federal brass are junk in this application because their Rockwell hardness is much less than Winchester.
I also shot the 115's at 3650 Using R#22, Fed 215 Primer.
If you try this experiment, then work up to these loads on your rifle. I would only use a modern bolt action rifle, because I have no idea what the pressures are in this round. I do know of 6 of the 257 WEatherby's that are shooting the 100's at 3800-3850 fps with amazing accuracy and one 30" Hart barrel that is shooting the 100's at 4000 fps.
the double radius was formed perfectly in the forming process! Just don't use too much lube or else you will get oil dents in the brass.
What every you do, use NEW Winchester brand of brass due to the fact that the primer pockets hole up much better than Rem or Fed.
Good luck!
What every you do, use NEW Winchester brand of brass due to the fact that the primer pockets hole up much better than Rem or Fed.
Good luck!