I own 2 257's. My magical number is 68.5 grains of IMR 4831 100 gr. bullet either sierra fb or Nosler bt. You dont need anything over 100 grain bullet to kill, i will not mention here how many 1 shot kills i made with this load. I do shoot more powder in 1 of mine but i have never seen 1 not shoot that load. Make sure it is de-coppered. As far as bedding brownls will work keep the bedding behind the recoil lug. Let me know how this works. BTW with this load get that bullet out close but not touching the lands. If you can get 1" or under at 100 keep it. Let me know how this works.