Load data for .257 Weath. Mag. + 117gr Sierra SPT Pro-Hunter
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
Cartridge:.257 Weath. Mag. load data
Case Length (L3):2.549" | 64.7 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.497" | 12.6 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:1:11.5
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Community Loads for .257 Weath. Mag. + 117gr Sierra SPT Pro-Hunter
Real loads for this combination shared by our community. Charge weights are only fully visible with an active Pro licence.
| Powder | Charge (gr) | C.O.L. | Barrel Length | Velocity (fps) | Pressure (psi) |
|---|---|---|---|---|---|
| 59.2 gr | 3.170" | 24.0" | 2896 fps | ••• | |
| 61.9 gr | 3.170" | 24.0" | 3002 fps | ••• | |
| 64.0 gr | 3.170" | 24.0" | 3032 fps | ••• | |
| ••• | 3.170" | 24.0" | 3085 fps | ••• | |
| ••• | 3.170" | 24.0" | 2845 fps | ••• | |
| ••• | 3.170" | 24.0" | 2976 fps | ••• | |
| ••• | 3.170" | 24.0" | 2950 fps | ••• | |
| ••• | 3.170" | 24.0" | 2724 fps | ••• | |
| ••• | 3.170" | 24.0" | 2808 fps | ••• | |
| ••• | 3.170" | 24.0" | 2931 fps | ••• | |
| ••• | 3.170" | 24.0" | 3081 fps | ••• | |
| ••• | 3.170" | 24.0" | 3168 fps | ••• | |
| ••• | 3.170" | 24.0" | 2853 fps | ••• | |
| ••• | 3.170" | 24.0" | 2949 fps | ••• | |
| ••• | 3.170" | 24.0" | 2807 fps | ••• | |
| ••• | 3.170" | 24.0" | 2928 fps | ••• | |
| ••• | 3.170" | 24.0" | 3040 fps | ••• | |
| ••• | 3.170" | 24.0" | 3092 fps | ••• | |
| ••• | 3.170" | 24.0" | 2607 fps | ••• | |
| ••• | 3.170" | 24.0" | 2731 fps | ••• | |
| ••• | 3.170" | 24.0" | 2848 fps | ••• | |
| ••• | 3.170" | 24.0" | 2952 fps | ••• | |
| ••• | 3.170" | 24.0" | 3043 fps | ••• | |
| ••• | 3.170" | 24.0" | 3087 fps | ••• | |
Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.