Load data for .257 Weath. Mag. + 100gr 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:0.388" | 9.8 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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Community Loads for .257 Weath. Mag. + 100gr 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) |
|---|---|---|---|---|---|
| 57.6 gr | 3.170" | 24.0" | 3162 fps | ••• | |
| 60.0 gr | 3.170" | 24.0" | 3268 fps | ••• | |
| 64.5 gr | 3.170" | 24.0" | 3175 fps | ••• | |
| ••• | 3.170" | 24.0" | 3067 fps | ••• | |
| ••• | 3.170" | 24.0" | 3166 fps | ••• | |
| ••• | 3.170" | 24.0" | 3266 fps | ••• | |
| ••• | 3.170" | 24.0" | 3309 fps | ••• | |
| ••• | 3.170" | 24.0" | 3355 fps | ••• | |
| ••• | 3.170" | 24.0" | 3089 fps | ••• | |
| ••• | 3.170" | 24.0" | 3211 fps | ••• | |
| ••• | 3.170" | 24.0" | 3272 fps | ••• | |
| ••• | 3.170" | 24.0" | 3324 fps | ••• | |
| ••• | 3.170" | 24.0" | 3134 fps | ••• | |
| ••• | 3.170" | 24.0" | 3255 fps | ••• | |
| ••• | 3.170" | 24.0" | 2924 fps | ••• | |
| ••• | 3.170" | 24.0" | 3047 fps | ••• | |
| ••• | 3.170" | 24.0" | 3164 fps | ••• | |
| ••• | 3.170" | 24.0" | 3274 fps | ••• | |
| ••• | 3.170" | 24.0" | 3322 fps | ••• | |
| ••• | 3.170" | 24.0" | 2818 fps | ••• | |
| ••• | 3.170" | 24.0" | 2913 fps | ••• | |
| ••• | 3.170" | 24.0" | 3015 fps | ••• | |
| ••• | 3.170" | 24.0" | 3119 fps | ••• | |
| ••• | 3.170" | 24.0" | 3172 fps | ••• | |
| ••• | 3.170" | 24.0" | 3296 fps | ••• | |
| ••• | 3.170" | 24.0" | 3326 fps | ••• | |
Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.