I read about a 257WBY shooter that had an 8" twist and when he loaded 133,he pressured out quickly not achieving the velocities he thought he would.I'd love to have a 257 WM in a 7-7.5 twist. That would allow one to shoot the highest BC copper bullets from Apex or Hammer as well as the heavy high BC Berger etc. It's about time Weatherby moves on from the 10 twist to something more modern like at least 8 twist. Not that there's much wrong with the 10 twist. All I've ever heard is that it kills like lightning.
When I was about 14 yrs old in 1958 an old boy in town sold Weatherbys out of his basement. He had all the pretty literature to get a young guy enthused. I couldn't afford a Weatherby so bought a pre 64 model 70 in 220 Swift. Not a Weatherby but close enough to get me excited.
I wonder how fast the 257 would shoot the Hammer 89 grain HBC? 3800-4000?
I'd think that's about the minimum he could spin it, and keep it stable.?I read about a 257WBY shooter that had an 8" twist and when he loaded 133,he pressured out quickly not achieving the velocities he thought he would.
That's not the case with my 7.5 twist 257 Wby and Berger 135s. I'm pushing them just under 3500 fps.I read about a 257WBY shooter that had an 8" twist and when he loaded 133,he pressured out quickly not achieving the velocities he thought he would.
Slow barrels exist, fast ones too.I read about a 257WBY shooter that had an 8" twist and when he loaded 133,he pressured out quickly not achieving the velocities he thought he would.
Have you tried H4831sc? That was the cat's meow for the 6.5/284.I'm getting 2900 mv with my 22" 25-284, 134 ELDM, and 54.5 grains of H1000. I bought some N560 to see if I can get a little more juice out of it. According to QL, it should be a hair over 3,000 at max. Its a very accurate rifle and load dev was very easy. It shoots the 110 ELDX at around 3150 with SB 6.5, and the 134 doesn't overtake in velocity until around 500 yards if I recall. I'm interested to try out the new TMK once its released.
That's not the case with my 7.5 twist 257 Wby and Berger 135s.
How many loads are you getting out of the brass? 82.9 Spread is a lot. I'd like to see picture of groups. I burn N570 in my 257 Bee. I've never tried Retumbo. The MAX load of Retumbo pushing 117 gr bullets is 66 grs and you say you're loading 74grs behind a 135 gr Berger? I find that extremely hard to believe.My 257Bee does just fine with 135 Bergers at almost 3500fps with a brand new Brux 7.5 twist barrel.
Long live the Bee!
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