Load data for .257 Ackley Improved + 100gr Sierra SPT Pro-Hunter
Based on Wildcat, 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 48,200 PSI / 3,323 bar.
Based on Wildcat, 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 48,200 PSI / 3,323 bar.
Load Specifications
ImperialMetric
Cartridge:.257 Ackley Improved load data
Case Length (L3):2.333" | 59.3 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.538" | 13.7 mm
Case Capacity:63 gow | 4.08 cm³
Primer Size:Large Rifle (LR)
Max. Pressure (Wildcat):48,200 psi | 3,323 bar
Barrel Length:24.0" | 610 mm
Min. Twist Rate:1:12.0
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Community Loads for .257 Ackley Improved + 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) |
|---|---|---|---|---|---|
| 46.0 gr | 2.775" | 26.0" | 3019 fps | ••• | |
| 47.3 gr | 2.775" | 26.0" | 3096 fps | ••• | |
| 45.8 gr | 2.775" | 26.0" | 2839 fps | ••• | |
| ••• | 2.775" | 26.0" | 2977 fps | ••• | |
| ••• | 2.775" | 26.0" | 3113 fps | ••• | |
| ••• | 2.775" | 26.0" | 3012 fps | ••• | |
| ••• | 2.775" | 26.0" | 2916 fps | ••• | |
| ••• | 2.775" | 26.0" | 2997 fps | ••• | |
| ••• | 2.775" | 26.0" | 3053 fps | ••• | |
Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.