No clue on the weight... don't have a scale small enough...
Whatever the Long Action Magnum calibers are.... ie - I originally picked this up to build a 300WM....
Long actions with a bolt face .Dia of .540 +/-
257 Weatherby, 264 Win Mag, 270 weatherby Mag, 7mm Rem Mag, 7mm Weatherby Mag, 7 STW,
7mm Rem Ultra Mag, 300 H & H, 300 Win Mag, 300 Weatherby Mag, 300 RUM, 303 Brit,
8mm Rem Mag, 338 Win Mag, 340 Weatherby Mag, 338 RUM, 375 H & H, 375 Weatherby,
375 RUM, 416 Rem Mag, 458 Win Mag, and the 458 Lott.