Load data for .256 Mag. Gibbs + 90gr Sierra Spitzer
Based on C.I.P., the max. allowed case length is 2.175 in / 55.25 mm, the max. cartridge length is 3.050 in / 77.47 mm, and the max. allowed pressure is 49,313 PSI / 3,400 bar.
Based on C.I.P., the max. allowed case length is 2.175 in / 55.25 mm, the max. cartridge length is 3.050 in / 77.47 mm, and the max. allowed pressure is 49,313 PSI / 3,400 bar.
Load Specifications
ImperialMetric
Bullet:.257 | 90gr | Spitzer
Cartridge:.256 Mag. Gibbs load data
Case Length (L3):2.173" | 55.2 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.257" | 6.5 mm
Case Capacity:56 gow | 3.63 cm³
Primer Size:Large Rifle (LR)
Max. Pressure (C.I.P.):49,313 psi | 3,400 bar
Barrel Length:24.0" | 610 mm
Min. Twist Rate:1:11.0
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