Load data for .257 Roberts + 100gr Hornady SP
395 suitable loads across 70 powder(s) for cartridge .257 Roberts with 100gr Hornady SP bullet.
The most recommended powders for this combination are Alliant Reloder-16, Somchem S365 and Alliant Reloder-17.
Based on C.I.P., the max. allowed case length is 2.233 in / 56.72 mm, the max. cartridge length is 2.775 in / 70.49 mm, and the max. allowed pressure is 51,488 PSI / 3,550 bar.
Based on C.I.P., the max. allowed case length is 2.233 in / 56.72 mm, the max. cartridge length is 2.775 in / 70.49 mm, and the max. allowed pressure is 51,488 PSI / 3,550 bar.
Load Specifications
ImperialMetric
Bullet:.257 | 100gr | SP
Cartridge:.257 Roberts load data
Case Length (L3):2.233" | 56.7 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.487" | 12.4 mm
Case Capacity:58 gow | 3.76 cm³
Primer Size:Large Rifle (LR)
Max. Pressure (C.I.P.):51,488 psi | 3,550 bar
Barrel Length:24.0" | 610 mm
Min. Twist Rate:1:11.5
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