Load Specifications
Load data in caliber 6 x 70 R with .243 | 75gr | Impala LW CFN bullet and 7 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% | 32,808 psi | 87% | 2697 fps | 98.7% |
| Accurate 4064 | <<locked>> | 84% | 32,967 psi | 87% | 2717 fps | 96.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 33,895 psi | 90% | 1913 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 98% | 33,257 psi | 88% | 1942 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 32,634 psi | 87% | 2612 fps | 96.9% |
| Vihtavuori N135 | <<locked>> | 82% | 32,547 psi | 86% | 2690 fps | 98.6% |
| Vihtavuori N140 | <<locked>> | 82% | 33,475 psi | 89% | 2677 fps | 96.5% |
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% | 30,995 psi | 82% | 2648 fps | 98.2% |
| Accurate 4064 | <<locked>> | 82% | 30,951 psi | 82% | 2661 fps | 95.6% |
| Hodgdon TrailBoss | 8.9 gr | 80% | 25,353 psi | 67% | 1719 fps | 100% |
| ReloadSwiss RS 14 | 9.1 gr | 80% | 25,628 psi | 68% | 1762 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 28,906 psi | 77% | 2507 fps | 95.4% |
| Vihtavuori N135 | <<locked>> | 80% | 30,414 psi | 81% | 2631 fps | 97.9% |
| Vihtavuori N140 | <<locked>> | 80% | 31,662 psi | 84% | 2628 fps | 95.8% |
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 7 powders for 6 x 70 R loaded with the .243 | 75gr | Impala LW CFN. Accurate 4064 delivers the highest muzzle velocity at 2,717 fps; across all powders the maximum-charge window runs from 1,913 fps to 2,717 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 7 of the 7 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 75.0 gr projectile in 0.243" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Hodgdon TrailBoss 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. ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for 6 x 70 R with the .243 | 75gr | Impala LW CFN 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.