Load data for .257 Roberts + 100gr Swift Scirocco

390 suitable loads across 70 powder(s) for cartridge .257 Roberts with 100gr Swift Scirocco bullet.

The most recommended powders for this combination are ReloadSwiss RS 60, ReloadSwiss RS 70 and Alliant Reloder-17.

.257 Roberts cartridge with combo bulletSeated DepthL3 = 2.233 in / 56.72 mmL6 = 2.775 in / 70.48 mmSeated Depth = .582 in / 14.78 mm

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
Case Length (L3):2.233" | 56.7 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.624" | 15.8 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:1:9.5

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