Load Specifications
Load data in caliber 6 x 70 R with .243 | 95gr | Sierra MatchKing bullet and 9 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% | 32,822 psi | 87% | 2434 fps | 99.8% |
| Accurate 4064 | <<locked>> | 84% | 33,069 psi | 88% | 2461 fps | 98.6% |
| Hodgdon TrailBoss | <<locked>> | 98% | 33,359 psi | 88% | 1677 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 98% | 33,562 psi | 89% | 1716 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 32,561 psi | 86% | 2503 fps | 96.5% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 33,591 psi | 89% | 2375 fps | 99% |
| Vihtavuori N135 | <<locked>> | 82% | 33,475 psi | 89% | 2441 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 88% | 33,997 psi | 90% | 2441 fps | 96.7% |
| Vihtavuori N540 | <<locked>> | 82% | 33,243 psi | 88% | 2425 fps | 98.1% |
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% | 30,719 psi | 81% | 2385 fps | 99.6% |
| Accurate 4064 | <<locked>> | 80% | 29,095 psi | 77% | 2362 fps | 97.4% |
| Hodgdon TrailBoss | 8.4 gr | 80% | 25,382 psi | 67% | 1512 fps | 100% |
| ReloadSwiss RS 14 | 8.5 gr | 80% | 25,251 psi | 67% | 1542 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 30,676 psi | 81% | 2451 fps | 95.6% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 29,530 psi | 78% | 2280 fps | 98% |
| Vihtavuori N135 | <<locked>> | 80% | 31,328 psi | 83% | 2392 fps | 99.6% |
| Vihtavuori N150 | <<locked>> | 84% | 29,617 psi | 79% | 2336 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 31,227 psi | 83% | 2375 fps | 97.4% |
Recommended = one of the top powders for this cartridge and bullet combination.
This overview compares 9 powders for 6 x 70 R loaded with the .243 | 95gr | Sierra MatchKing. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,503 fps; across all powders the maximum-charge window runs from 1,677 fps to 2,503 fps. Hodgdon TrailBoss gives the best case fill at 98 %, and 9 of the 9 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (260 MPa), the top charges use 86–90 %, leaving at least 10 % headroom. The 95.0 gr projectile in 0.243" calls for a 1:8.5 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 | 95gr | Sierra MatchKing 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.