Load data for .257 Weath. Mag. + 87gr Speer TNT
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
Bullet:.257 | 87gr | TNT
Cartridge:.257 Weath. Mag. load data
Case Length (L3):2.549" | 64.7 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.299" | 7.6 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:1:12.0
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Community Loads for .257 Weath. Mag. + 87gr Speer TNT
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) |
|---|---|---|---|---|---|
| 68.0 gr | 3.170" | — | 3305 fps | ••• | |
| 70.0 gr | 3.170" | — | 3406 fps | ••• | |
| 64.0 gr | 3.170" | — | 3348 fps | ••• | |
| ••• | 3.170" | — | 3537 fps | ••• | |
| ••• | 3.170" | — | 3381 fps | ••• | |
| ••• | 3.170" | — | 3573 fps | ••• | |
| ••• | 3.170" | — | 3361 fps | ••• | |
| ••• | 3.170" | — | 3554 fps | ••• | |
| ••• | 3.170" | — | 3619 fps | ••• | |
| ••• | 3.170" | — | 3827 fps | ••• | |
| ••• | 3.170" | — | 3423 fps | ••• | |
| ••• | 3.170" | — | 3511 fps | ••• | |
| ••• | 3.170" | — | 3397 fps | ••• | |
| ••• | 3.170" | — | 3598 fps | ••• | |
| ••• | 3.170" | — | 3399 fps | ••• | |
| ••• | 3.170" | — | 3498 fps | ••• | |
| ••• | 3.170" | — | 3361 fps | ••• | |
| ••• | 3.170" | — | 3567 fps | ••• | |
Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.