Load data for .257 Roberts + 70gr Sierra Tipped VarmintKing
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
ImperialMetric
Cartridge:.257 Roberts load data
Case Length (L3):2.233" | 56.7 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.407" | 10.3 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:1:11.5
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Community Loads for .257 Roberts + 70gr Sierra Tipped VarmintKing
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) |
|---|---|---|---|---|---|
| 42.5 gr | 2.700" | 22.0" | 2958 fps | ••• | |
| 44.4 gr | 2.700" | 22.0" | 3083 fps | ••• | |
| 46.2 gr | 2.700" | 22.0" | 3201 fps | ••• | |
| ••• | 2.700" | 22.0" | 2979 fps | ••• | |
| ••• | 2.700" | 22.0" | 3048 fps | ••• | |
| ••• | 2.700" | 22.0" | 3116 fps | ••• | |
| ••• | 2.700" | 22.0" | 3186 fps | ••• | |
| ••• | 2.700" | 22.0" | 2897 fps | ••• | |
| ••• | 2.700" | 22.0" | 3002 fps | ••• | |
| ••• | 2.700" | 22.0" | 3106 fps | ••• | |
| ••• | 2.700" | 22.0" | 3210 fps | ••• | |
| ••• | 2.700" | 22.0" | 3315 fps | ••• | |
| ••• | 2.700" | 22.0" | 2946 fps | ••• | |
| ••• | 2.700" | 22.0" | 3024 fps | ••• | |
| ••• | 2.700" | 22.0" | 3099 fps | ••• | |
| ••• | 2.700" | 22.0" | 3095 fps | ••• | |
| ••• | 2.700" | 22.0" | 3166 fps | ••• | |
| ••• | 2.700" | 22.0" | 3090 fps | ••• | |
| ••• | 2.700" | 22.0" | 3212 fps | ••• | |
| ••• | 2.700" | 22.0" | 3026 fps | ••• | |
| ••• | 2.700" | 22.0" | 3133 fps | ••• | |
| ••• | 2.700" | 22.0" | 3239 fps | ••• | |
| ••• | 2.700" | 22.0" | 3032 fps | ••• | |
| ••• | 2.700" | 22.0" | 3122 fps | ••• | |
| ••• | 2.700" | 22.0" | 3204 fps | ••• | |
| ••• | 2.700" | 22.0" | 3294 fps | ••• | |
| ••• | 2.700" | 22.0" | 3086 fps | ••• | |
| ••• | 2.700" | 22.0" | 3141 fps | ••• | |
| ••• | 2.700" | 22.0" | 3195 fps | ••• | |
| ••• | 2.700" | 22.0" | 3079 fps | ••• | |
| ••• | 2.700" | 22.0" | 3157 fps | ••• | |
| ••• | 2.700" | 22.0" | 3241 fps | ••• | |
| ••• | 2.700" | 22.0" | 2967 fps | ••• | |
| ••• | 2.700" | 22.0" | 3035 fps | ••• | |
| ••• | 2.700" | 22.0" | 3112 fps | ••• | |
| ••• | 2.700" | 22.0" | 3181 fps | ••• | |
| ••• | 2.700" | 22.0" | 3048 fps | ••• | |
| ••• | 2.700" | 22.0" | 3182 fps | ••• | |
| ••• | 2.700" | 22.0" | 3308 fps | ••• | |
| ••• | 2.700" | 22.0" | 3061 fps | ••• | |
| ••• | 2.700" | 22.0" | 3138 fps | ••• | |
| ••• | 2.700" | 22.0" | 3214 fps | ••• | |
| ••• | 2.700" | 22.0" | 3001 fps | ••• | |
| ••• | 2.700" | 22.0" | 3088 fps | ••• | |
| ••• | 2.700" | 22.0" | 3166 fps | ••• | |
| ••• | 2.700" | 22.0" | 2947 fps | ••• | |
| ••• | 2.700" | 22.0" | 3033 fps | ••• | |
| ••• | 2.700" | 22.0" | 3124 fps | ••• | |
| ••• | 2.700" | 22.0" | 3206 fps | ••• | |
| ••• | 2.700" | 22.0" | 3293 fps | ••• | |
Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.