Load Specifications
Load data in caliber 6 x 70 R with .243 | 85gr | Sierra VarmintKing bullet and 8 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are 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: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 82% | 32,634 psi | 87% | 2582 fps | 99.6% |
| Accurate 4064 | <<locked>> | 84% | 33,054 psi | 88% | 2612 fps | 98% |
| Hodgdon TrailBoss | <<locked>> | 98% | 32,982 psi | 87% | 1801 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 98% | 33,112 psi | 88% | 1841 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 33,489 psi | 89% | 2523 fps | 98.5% |
| Vihtavuori N135 | <<locked>> | 82% | 33,185 psi | 88% | 2589 fps | 99.6% |
| Vihtavuori N150 | <<locked>> | 88% | 33,591 psi | 89% | 2579 fps | 95.8% |
| Vihtavuori N540 | <<locked>> | 82% | 33,127 psi | 88% | 2569 fps | 97.4% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 80% | 30,690 psi | 81% | 2536 fps | 99.3% |
| Accurate 4064 | <<locked>> | 80% | 29,008 psi | 77% | 2503 fps | 96.6% |
| Hodgdon TrailBoss | 9.1 gr | 80% | 25,251 psi | 67% | 1631 fps | 100% |
| ReloadSwiss RS 14 | 9.3 gr | 80% | 25,454 psi | 68% | 1673 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 29,428 psi | 78% | 2421 fps | 97.3% |
| Vihtavuori N135 | <<locked>> | 80% | 31,198 psi | 83% | 2539 fps | 99.3% |
| Vihtavuori N150 | <<locked>> | 86% | 31,676 psi | 84% | 2533 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 30,980 psi | 82% | 2516 fps | 96.7% |
Recommended = one of the top powders for this cartridge and bullet combination.
This overview compares 8 powders for 6 x 70 R loaded with the .243 | 85gr | Sierra VarmintKing. Accurate 4064 delivers the highest muzzle velocity at 2,612 fps; across all powders the maximum-charge window runs from 1,801 fps to 2,612 fps. Hodgdon TrailBoss gives the best case fill at 98 %, and 8 of the 8 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (260 MPa), the top charges use 87–89 %, leaving at least 11 % headroom. The 85.0 gr projectile in 0.243" calls for a 1:11.0 twist; slower twists will usually not stabilise this weight. ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for 6 x 70 R with the .243 | 85gr | Sierra VarmintKing 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.