Load Specifications
Load data in caliber .458 SOCOM with .458 | 400gr | Barnes Buster FN FB bullet and 6 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N120, 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: 16"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI AR 2207 | <<locked>> | 90% | 30,400 psi | 87% | 1604 fps | 96.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 28,195 psi | 81% | 1043 fps | 100% |
| Lovex S053 | <<locked>> | 82% | 30,298 psi | 87% | 1535 fps | 98.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 27,630 psi | 79% | 1066 fps | 100% |
| SNPE Vectan BA6 1/2 | <<locked>> | 84% | 30,574 psi | 87% | 1476 fps | 100% |
| Vihtavuori N120 | <<locked>> | 90% | 30,879 psi | 88% | 1591 fps | 97.8% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 16"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI AR 2207 | <<locked>> | 86% | 26,992 psi | 77% | 1539 fps | 95% |
| Hodgdon TrailBoss | 11.3 gr | 80% | 20,624 psi | 59% | 928 fps | 100% |
| Lovex S053 | <<locked>> | 80% | 28,689 psi | 82% | 1506 fps | 97.8% |
| ReloadSwiss RS 14 | 11.5 gr | 80% | 20,146 psi | 58% | 948 fps | 100% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 27,354 psi | 78% | 1424 fps | 100% |
| Vihtavuori N120 | 32.2 gr | 82% | 24,627 psi | 70% | 1470 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 13 powders for .458 SOCOM loaded with the .458 | 400gr | Barnes Buster FN FB. Alliant Reloder-10x delivers the highest muzzle velocity at 1,631 fps; across all powders the maximum-charge window runs from 1,043 fps to 1,631 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 13 of the 13 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (241 MPa), the top charges use 79–90 %, leaving at least 10 % headroom. 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. Vihtavuori N120, ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for .458 SOCOM with the .458 | 400gr | Barnes Buster FN FB they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-10x, Alliant Reloder-7, IMR 4198 burn incompletely and react more sensitively to barrel length and temperature. Hodgdon TrailBoss, ReloadSwiss RS 14 stay subsonic at start load. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.