Load data for .257 Weath. Mag. + 87gr Speer MHP
518 suitable loads across 78 powder(s) for cartridge .257 Weath. Mag. with 87gr Speer MHP bullet.
The most recommended powders for this combination are Norma MRP, Vihtavuori N560 and Alliant Reloder-26.
Based on C.I.P., the max. allowed case length is 2.549 in / 64.74 mm, the max. cartridge length is 3.209 in / 81.51 mm, and the max. allowed pressure is 63,817 PSI / 4,400 bar.
Based on C.I.P., the max. allowed case length is 2.549 in / 64.74 mm, the max. cartridge length is 3.209 in / 81.51 mm, and the max. allowed pressure is 63,817 PSI / 4,400 bar.
Load Specifications
ImperialMetric
Bullet:.257 | 87gr | MHP
Cartridge:.257 Weath. Mag. load data
Case Length (L3):2.549" | 64.7 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.347" | 8.8 mm
Case Capacity:84 gow | 5.44 cm³
Primer Size:Large Rifle Magnum (LRM)
Max. Pressure (C.I.P.):63,817 psi | 4,400 bar
Barrel Length:26.0" | 660 mm
Min. Twist Rate:1:12.0
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