Load Specifications
Load data in caliber 6 x 70 R with .243 | 90gr | Berger BT M T 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% | 32,242 psi | 86% | 2493 fps | 99.6% |
| Accurate 4064 | <<locked>> | 84% | 32,750 psi | 87% | 2523 fps | 98.2% |
| Hodgdon TrailBoss | <<locked>> | 98% | 33,272 psi | 88% | 1732 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 98% | 33,460 psi | 89% | 1772 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 33,127 psi | 88% | 2434 fps | 98.6% |
| Vihtavuori N135 | <<locked>> | 82% | 33,011 psi | 88% | 2500 fps | 99.7% |
| Vihtavuori N140 | <<locked>> | 82% | 34,055 psi | 90% | 2500 fps | 98.4% |
| Vihtavuori N150 | <<locked>> | 88% | 33,243 psi | 88% | 2490 fps | 96% |
| Vihtavuori N540 | <<locked>> | 82% | 32,967 psi | 87% | 2487 fps | 97.6% |
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% | 30,197 psi | 80% | 2444 fps | 99.3% |
| Accurate 4064 | <<locked>> | 80% | 28,587 psi | 76% | 2415 fps | 96.8% |
| Hodgdon TrailBoss | 8.6 gr | 80% | 25,121 psi | 67% | 1562 fps | 100% |
| ReloadSwiss RS 14 | 8.8 gr | 80% | 25,367 psi | 67% | 1601 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 29,225 psi | 78% | 2339 fps | 97.5% |
| Vihtavuori N135 | <<locked>> | 80% | 30,937 psi | 82% | 2454 fps | 99.4% |
| Vihtavuori N140 | <<locked>> | 80% | 32,039 psi | 85% | 2451 fps | 97.8% |
| Vihtavuori N150 | <<locked>> | 86% | 31,270 psi | 83% | 2444 fps | 95.2% |
| Vihtavuori N540 | <<locked>> | 80% | 30,705 psi | 81% | 2431 fps | 96.8% |
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 | 90gr | Berger BT M T. Accurate 4064 delivers the highest muzzle velocity at 2,523 fps; across all powders the maximum-charge window runs from 1,732 fps to 2,523 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 90.0 gr projectile in 0.243" calls for a 1:9.0 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 | 90gr | Berger BT M T 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.