Load Specifications
Load data in caliber .256 Win. Mag. with .257 | 52gr | Peregrine VRG-3 bullet and 7 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon LilGun, Lovex S040 and Vihtavuori N110.
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.
A valid access license is required to use the Personalized Load Calculator.
You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI AR 2205ᴾ | <<locked>> | 100% | 45,455 psi | 90% | 2812 fps | 96.3% |
| Hodgdon LilGun | <<locked>> | 96% | 45,426 psi | 89% | 3045 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 22,872 psi | 45% | 1791 fps | 100% |
| Lovex S040 | <<locked>> | 92% | 43,918 psi | 87% | 2848 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 21,770 psi | 43% | 1827 fps | 100% |
| SNPE Vectan BA6 1/2ᴾ | <<locked>> | 100% | 29,457 psi | 58% | 2556 fps | 98.7% |
| Vihtavuori N110ᴾ | <<locked>> | 100% | 37,202 psi | 73% | 2792 fps | 99% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI AR 2205 | <<locked>> | 96% | 40,553 psi | 80% | 2726 fps | 95% |
| Hodgdon LilGun | 14.1 gr | 80% | 25,831 psi | 51% | 2625 fps | 96.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 16,650 psi | 33% | 1611 fps | 100% |
| Lovex S040 | 12.1 gr | 80% | 30,734 psi | 61% | 2572 fps | 96.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 16,012 psi | 32% | 1647 fps | 100% |
| SNPE Vectan BA6 1/2 | <<locked>> | 88% | 21,393 psi | 42% | 2313 fps | 95.3% |
| Vihtavuori N110 | 12.5 gr | 86% | 24,642 psi | 49% | 2484 fps | 95.2% |
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 9 powders for .256 Win. Mag. loaded with the .257 | 52gr | Peregrine VRG-3. Hodgdon LilGun delivers the highest muzzle velocity at 3,045 fps; across all powders the maximum-charge window runs from 1,791 fps to 3,045 fps. ADI AR 2205 gives the best case fill at 100 %, and 9 of the 9 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (350 MPa), the top charges use 43–90 %, leaving at least 10 % headroom. ADI AR 2205, Hodgdon TrailBoss, Lovex S053 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. Hodgdon LilGun, Lovex S040, Vihtavuori N110 rank at the top here: for .256 Win. Mag. with the .257 | 52gr | Peregrine VRG-3 they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate No. 11 FS, Lovex S053 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.