Load Specifications
Load data in caliber .25-35 Win. with .257 | 70gr | Impala LWHV LS bullet and 10 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are IMR 4198, ReloadSwiss RS 14 and Hodgdon TrailBoss.
Important Notice: DO NOT go below Minimum Charge or above Maximum Charge. Since we have no control over the equipment and components used, any responsibility and liability for the results achieved is rejected.
Only powders/loads that match the current filter criteria are displayed: max pressure of a load ≤ 90% of max. standardized pressure, fill rate ≥ 80% and propellant combustion ≥ 95%. Use the sliders above the tables to adjust these thresholds.
Charge: Powder weight in grains. Start with the minimum load and work up carefully.
FR (Fill Rate): Case fill as a percentage. Values above 100% mean compressed loads.
MaxP / %: Maximum chamber pressure in bar and as a percentage of the standardized maximum for this caliber.
V(0): Muzzle velocity in feet per second (fps) at the standardized barrel length.
z (Powder Burn): Estimated propellant combustion percentage at bullet exit.
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Max Load - Barrel Length: 20"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI AR 2207 | <<locked>> | 86% | 39,929 psi | 90% | 2848 fps | 99.2% |
| Alliant AR-Comp | <<locked>> | 98% | 38,116 psi | 86% | 2867 fps | 96.6% |
| Alliant Reloder-10x | <<locked>> | 92% | 39,856 psi | 90% | 2858 fps | 96% |
| Alliant Reloder-7 | <<locked>> | 84% | 39,494 psi | 89% | 2782 fps | 96.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 31,285 psi | 71% | 1870 fps | 100% |
| IMR 4198 | <<locked>> | 90% | 39,885 psi | 90% | 2812 fps | 96.9% |
| Norma 200 | <<locked>> | 86% | 38,145 psi | 86% | 2799 fps | 96.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 31,154 psi | 70% | 1916 fps | 100% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 39,320 psi | 89% | 2612 fps | 100% |
| Vihtavuori N120 | <<locked>> | 84% | 37,536 psi | 85% | 2759 fps | 99.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 20"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI AR 2207 | <<locked>> | 80% | 33,257 psi | 75% | 2687 fps | 97.8% |
| Alliant AR-Comp | <<locked>> | 96% | 36,216 psi | 82% | 2818 fps | 95.9% |
| Alliant Reloder-10x | <<locked>> | 90% | 37,753 psi | 85% | 2808 fps | 95.3% |
| Alliant Reloder-7 | <<locked>> | 80% | 35,244 psi | 80% | 2680 fps | 95% |
| Hodgdon TrailBoss | 7.8 gr | 80% | 23,380 psi | 53% | 1677 fps | 100% |
| IMR 4198 | 22.3 gr | 86% | 35,607 psi | 80% | 2703 fps | 95.5% |
| Norma 200 | <<locked>> | 84% | 36,201 psi | 82% | 2753 fps | 95.7% |
| ReloadSwiss RS 14 | 8 gr | 80% | 23,438 psi | 53% | 1722 fps | 100% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 37,246 psi | 84% | 2572 fps | 100% |
| Vihtavuori N120 | <<locked>> | 80% | 33,344 psi | 75% | 2657 fps | 98.8% |
Recommended = one of the top powders for this cartridge and bullet combination.
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 10 powders for .25-35 Win. loaded with the .257 | 70gr | Impala LWHV LS. Alliant AR-Comp delivers the highest muzzle velocity at 2,867 fps; across all powders the maximum-charge window runs from 1,870 fps to 2,867 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 10 of the 10 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (305 MPa), the top charges use 70–90 %, leaving at least 10 % headroom. The 70.0 gr projectile in 0.257" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Hodgdon TrailBoss, ReloadSwiss RS 14 reach 100 % fill or more at maximum charge, so these are compressed loads: they need a long drop tube to seat cleanly and react sensitively to the case capacity of your own brass lot. IMR 4198, ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for .25-35 Win. with the .257 | 70gr | Impala LWHV LS they combine a high case fill with complete burn and sit in the upper velocity band. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.