Load Specifications
Load data in caliber 8 x 58 R with .318 | 175gr | Peregrine VLR-4 bullet and 5 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant AR-Comp, 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: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Alliant AR-Comp | <<locked>> | 92% | 28,485 psi | 89% | 2024 fps | 97.3% |
| Alliant Reloder-10x | <<locked>> | 84% | 27,514 psi | 86% | 1965 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 96% | 28,718 psi | 90% | 1309 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 96% | 28,326 psi | 89% | 1342 fps | 100% |
| Vihtavuori N130 | <<locked>> | 86% | 28,616 psi | 90% | 1936 fps | 95.9% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Alliant AR-Comp | 25.7 gr | 88% | 25,106 psi | 79% | 1939 fps | 95.5% |
| Alliant Reloder-10x | <<locked>> | 82% | 25,715 psi | 81% | 1923 fps | 95.1% |
| Hodgdon TrailBoss | 8.1 gr | 80% | 21,959 psi | 69% | 1188 fps | 100% |
| ReloadSwiss RS 14 | 8.3 gr | 80% | 21,785 psi | 68% | 1217 fps | 100% |
| Vihtavuori N130 | <<locked>> | 84% | 27,108 psi | 85% | 1903 fps | 95.2% |
Recommended = one of the top powders for this cartridge and bullet combination.
This overview compares 5 powders for 8 x 58 R loaded with the .318 | 175gr | Peregrine VLR-4. Alliant AR-Comp delivers the highest muzzle velocity at 2,024 fps; across all powders the maximum-charge window runs from 1,309 fps to 2,024 fps. Hodgdon TrailBoss gives the best case fill at 96 %, and 5 of the 5 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (220 MPa), the top charges use 86–90 %, leaving at least 10 % headroom. The 175.0 gr projectile in 0.318" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Alliant AR-Comp, ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for 8 x 58 R with the .318 | 175gr | Peregrine VLR-4 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.