Load data for .257 Roberts + 100gr Sierra SPT Pro-Hunter
377 suitable loads across 71 powder(s) for cartridge .257 Roberts with 100gr Sierra SPT Pro-Hunter bullet.
The most recommended powders for this combination are Somchem S365, ReloadSwiss RS 70 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
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Community Loads for .257 Roberts + 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) |
|---|---|---|---|---|---|
| 41.5 gr | 2.775" | 22.0" | 2761 fps | ••• | |
| 43.0 gr | 2.775" | 22.0" | 2851 fps | ••• | |
| 38.9 gr | 2.775" | 22.0" | 2794 fps | ••• | |
| ••• | 2.775" | 22.0" | 2883 fps | ••• | |
| ••• | 2.775" | 22.0" | 2875 fps | ••• | |
| ••• | 2.775" | 22.0" | 2530 fps | ••• | |
| ••• | 2.775" | 22.0" | 2608 fps | ••• | |
| ••• | 2.775" | 22.0" | 2688 fps | ••• | |
| ••• | 2.775" | 22.0" | 2770 fps | ••• | |
| ••• | 2.775" | 22.0" | 2766 fps | ••• | |
| ••• | 2.775" | 22.0" | 2872 fps | ••• | |
| ••• | 2.775" | 22.0" | 2615 fps | ••• | |
| ••• | 2.775" | 22.0" | 2712 fps | ••• | |
| ••• | 2.775" | 22.0" | 2811 fps | ••• | |
| ••• | 2.775" | 22.0" | 2909 fps | ••• | |
| ••• | 2.775" | 22.0" | 2833 fps | ••• | |
| ••• | 2.775" | 22.0" | 2903 fps | ••• | |
| ••• | 2.775" | 22.0" | 2746 fps | ••• | |
| ••• | 2.775" | 22.0" | 2845 fps | ••• | |
| ••• | 2.775" | 22.0" | 2847 fps | ••• | |
Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.