Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 155gr | Lapua Mega bullet and 39 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ADI AR 2218, Vihtavuori N570 and Alliant Reloder-50.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 82% | 58,044 psi | 89% | 2805 fps | 100% |
| Accurate 8700 | <<locked>> | 98% | 55,114 psi | 85% | 2881 fps | 98.8% |
| ADI AR 2213 | <<locked>> | 82% | 57,957 psi | 89% | 2913 fps | 100% |
| ADI AR 2217 | <<locked>> | 90% | 58,204 psi | 90% | 2913 fps | 100% |
| ADI AR 2218 | <<locked>> | 92% | 54,940 psi | 85% | 2986 fps | 99.4% |
| ADI AR 2225 | <<locked>> | 92% | 58,421 psi | 90% | 2933 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 82% | 58,523 psi | 90% | 2907 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 82% | 56,956 psi | 88% | 2808 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 86% | 58,247 psi | 90% | 2890 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 57,116 psi | 88% | 2959 fps | 99.4% |
| Alliant Reloder-50 | <<locked>> | 94% | 57,696 psi | 89% | 2959 fps | 99.1% |
| Baschieri & Pellagri 109 | <<locked>> | 84% | 57,493 psi | 88% | 2881 fps | 99.5% |
| Bofors RP15 | <<locked>> | 84% | 57,972 psi | 89% | 2900 fps | 100% |
| Bofors RP30 | <<locked>> | 88% | 58,146 psi | 89% | 2923 fps | 100% |
| Bofors RP5 | <<locked>> | 82% | 58,523 psi | 90% | 2907 fps | 100% |
| Hodgdon H1000 | <<locked>> | 86% | 55,347 psi | 85% | 2867 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 58,653 psi | 90% | 2989 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,247 psi | 59% | 1850 fps | 100% |
| IMR 7828 SSC | <<locked>> | 82% | 56,695 psi | 87% | 2900 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 88% | 58,262 psi | 90% | 2844 fps | 97.5% |
| IMR 8133 Enduron | <<locked>> | 94% | 57,392 psi | 88% | 2923 fps | 100% |
| Lovex D100 | <<locked>> | 90% | 56,173 psi | 86% | 2841 fps | 96.1% |
| Lovex S071 | <<locked>> | 86% | 56,695 psi | 87% | 2789 fps | 100% |
| Norma 217 | <<locked>> | 92% | 55,347 psi | 85% | 2887 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 58,407 psi | 90% | 2927 fps | 100% |
| Ramshot LRT | <<locked>> | 94% | 58,552 psi | 90% | 2979 fps | 96.2% |
| Ramshot Magnum | <<locked>> | 84% | 56,884 psi | 88% | 2854 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,450 psi | 61% | 1896 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 84% | 55,027 psi | 85% | 2910 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 88% | 58,291 psi | 90% | 2956 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 90% | 56,173 psi | 86% | 2841 fps | 96.1% |
| SNPE Vectan SP 13 | <<locked>> | 98% | 56,623 psi | 87% | 2884 fps | 98.8% |
| Vihtavuori 20N29ᴾ | <<locked>> | 100% | 53,940 psi | 83% | 2858 fps | 97% |
| Vihtavuori N165 | <<locked>> | 84% | 58,595 psi | 90% | 2831 fps | 100% |
| Vihtavuori N170 | <<locked>> | 88% | 58,349 psi | 90% | 2884 fps | 98.6% |
| Vihtavuori N565 | <<locked>> | 84% | 56,086 psi | 86% | 2877 fps | 100% |
| Vihtavuori N568 | <<locked>> | 88% | 58,479 psi | 90% | 2956 fps | 99.9% |
| Vihtavuori N570 | <<locked>> | 88% | 56,289 psi | 87% | 2963 fps | 99.1% |
| Winchester Supreme 780 | <<locked>> | 82% | 58,102 psi | 89% | 2841 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 54,346 psi | 84% | 2753 fps | 100% |
| Accurate 8700 | <<locked>> | 90% | 41,191 psi | 63% | 2621 fps | 95.4% |
| ADI AR 2213 | <<locked>> | 80% | 54,143 psi | 83% | 2854 fps | 100% |
| ADI AR 2217 | <<locked>> | 80% | 41,046 psi | 63% | 2615 fps | 99.1% |
| ADI AR 2218 | 76.1 gr | 84% | 40,872 psi | 63% | 2697 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 80% | 38,464 psi | 59% | 2589 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 54,853 psi | 84% | 2851 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 80% | 53,330 psi | 82% | 2756 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 47,558 psi | 73% | 2726 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 80% | 39,566 psi | 61% | 2618 fps | 95.2% |
| Alliant Reloder-50 | 79.1 gr | 86% | 43,221 psi | 67% | 2690 fps | 95.9% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 50,502 psi | 78% | 2762 fps | 98.7% |
| Bofors RP15 | <<locked>> | 80% | 51,082 psi | 79% | 2789 fps | 100% |
| Bofors RP30 | <<locked>> | 80% | 44,527 psi | 69% | 2687 fps | 99.5% |
| Bofors RP5 | <<locked>> | 80% | 54,853 psi | 84% | 2851 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 44,817 psi | 69% | 2687 fps | 99.8% |
| Hodgdon Retumbo | <<locked>> | 80% | 47,456 psi | 73% | 2808 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,819 psi | 44% | 1657 fps | 100% |
| IMR 7828 SSC | <<locked>> | 80% | 52,982 psi | 82% | 2841 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 82% | 48,167 psi | 74% | 2667 fps | 95.1% |
| IMR 8133 Enduron | <<locked>> | 80% | 35,810 psi | 55% | 2510 fps | 97.4% |
| Lovex D100 | <<locked>> | 88% | 52,417 psi | 81% | 2776 fps | 95.1% |
| Lovex S071 | <<locked>> | 80% | 47,036 psi | 72% | 2638 fps | 100% |
| Norma 217 | <<locked>> | 80% | 36,753 psi | 57% | 2543 fps | 99.3% |
| Ramshot Grand | <<locked>> | 80% | 54,462 psi | 84% | 2867 fps | 100% |
| Ramshot LRT | <<locked>> | 92% | 54,346 psi | 84% | 2910 fps | 95.2% |
| Ramshot Magnum | <<locked>> | 80% | 49,168 psi | 76% | 2736 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,791 psi | 46% | 1696 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 47,384 psi | 73% | 2785 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 43,352 psi | 67% | 2690 fps | 98.4% |
| Shooters World 50 BMG | <<locked>> | 88% | 52,417 psi | 81% | 2776 fps | 95.1% |
| SNPE Vectan SP 13 | <<locked>> | 90% | 43,279 psi | 67% | 2641 fps | 95.7% |
| Vihtavuori 20N29 | <<locked>> | 96% | 46,934 psi | 72% | 2733 fps | 95% |
| Vihtavuori N165 | <<locked>> | 80% | 51,488 psi | 79% | 2726 fps | 100% |
| Vihtavuori N170 | <<locked>> | 80% | 44,643 psi | 69% | 2638 fps | 95.6% |
| Vihtavuori N565 | <<locked>> | 80% | 49,052 psi | 75% | 2759 fps | 99.7% |
| Vihtavuori N568 | <<locked>> | 80% | 44,019 psi | 68% | 2697 fps | 98.2% |
| Vihtavuori N570 | 71 gr | 80% | 42,308 psi | 65% | 2694 fps | 95.8% |
| Winchester Supreme 780 | <<locked>> | 80% | 54,389 psi | 84% | 2785 fps | 100% |
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 39 powders for 6.5-300 Weatherby Mag. loaded with the .264 | 155gr | Lapua Mega. Hodgdon Retumbo delivers the highest muzzle velocity at 2,989 fps; across all powders the maximum-charge window runs from 1,850 fps to 2,989 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 39 of the 39 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 59–90 %, leaving at least 10 % headroom. The 155.0 gr projectile in 0.264" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Hodgdon TrailBoss, ReloadSwiss RS 14, Vihtavuori 20N29 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. ADI AR 2218, Vihtavuori N570, Alliant Reloder-50 rank at the top here: for 6.5-300 Weatherby Mag. with the .264 | 155gr | Lapua Mega 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.