Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 140gr | Sierra MatchKing bullet and 49 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>> | 84% | 57,638 psi | 89% | 2933 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 53,693 psi | 83% | 2976 fps | 97.7% |
| Accurate MAGPRO | <<locked>> | 82% | 56,695 psi | 87% | 3041 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 82% | 58,291 psi | 90% | 3018 fps | 100% |
| ADI AR 2213 | <<locked>> | 84% | 57,246 psi | 88% | 3038 fps | 100% |
| ADI AR 2217 | <<locked>> | 92% | 57,058 psi | 88% | 3028 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 57,696 psi | 89% | 3159 fps | 99.2% |
| ADI AR 2225 | <<locked>> | 94% | 57,014 psi | 88% | 3051 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 57,914 psi | 89% | 3009 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 57,769 psi | 89% | 3031 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 84% | 56,202 psi | 86% | 2933 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 88% | 57,101 psi | 88% | 3015 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 55,637 psi | 86% | 3061 fps | 98.5% |
| Alliant Reloder-50 | <<locked>> | 96% | 56,188 psi | 86% | 3061 fps | 98.2% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 57,232 psi | 88% | 2999 fps | 98.9% |
| Bofors RP15 | <<locked>> | 86% | 57,435 psi | 88% | 3025 fps | 100% |
| Bofors RP30 | <<locked>> | 90% | 56,985 psi | 88% | 3038 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 57,769 psi | 89% | 3031 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 58,450 psi | 90% | 3048 fps | 100% |
| Hodgdon H4831 | <<locked>> | 82% | 55,811 psi | 86% | 2969 fps | 99.7% |
| Hodgdon H4831 SC | <<locked>> | 84% | 58,479 psi | 90% | 3012 fps | 99.9% |
| Hodgdon Retumbo | <<locked>> | 88% | 57,203 psi | 88% | 3114 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,043 psi | 59% | 1939 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 55,782 psi | 86% | 2943 fps | 99.8% |
| IMR 7828 SSC | <<locked>> | 84% | 56,086 psi | 86% | 3025 fps | 99.9% |
| IMR 7977 Enduron | <<locked>> | 90% | 58,073 psi | 89% | 2959 fps | 96.3% |
| IMR 8133 Enduron | <<locked>> | 96% | 55,927 psi | 86% | 3035 fps | 100% |
| Lovex S071 | <<locked>> | 88% | 56,086 psi | 86% | 2910 fps | 100% |
| Norma 217 | <<locked>> | 96% | 57,479 psi | 88% | 3054 fps | 100% |
| Norma MRP | <<locked>> | 82% | 58,189 psi | 90% | 3045 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 57,493 psi | 88% | 3048 fps | 100% |
| Ramshot Magnum | <<locked>> | 86% | 55,985 psi | 86% | 2976 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,189 psi | 60% | 1985 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 57,841 psi | 89% | 3094 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 56,898 psi | 88% | 3064 fps | 99.7% |
| Rottweil R 904 | <<locked>> | 82% | 58,421 psi | 90% | 2989 fps | 100% |
| Rottweil R 905 | <<locked>> | 82% | 57,740 psi | 89% | 2999 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 55,477 psi | 85% | 2986 fps | 97.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 57,377 psi | 88% | 2995 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 57,957 psi | 89% | 2966 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 58,305 psi | 90% | 2959 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 57,769 psi | 89% | 2995 fps | 97.7% |
| Vihtavuori N555 | <<locked>> | 82% | 57,856 psi | 89% | 2963 fps | 100% |
| Vihtavuori N560 | <<locked>> | 82% | 57,392 psi | 88% | 3051 fps | 99.9% |
| Vihtavuori N565 | <<locked>> | 86% | 55,056 psi | 85% | 2992 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 90% | 57,261 psi | 88% | 3068 fps | 99.6% |
| Vihtavuori N570 | <<locked>> | 90% | 54,940 psi | 85% | 3071 fps | 98.1% |
| Winchester StaBALL HD | <<locked>> | 84% | 57,783 psi | 89% | 3031 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 57,885 psi | 89% | 2966 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% | 50,459 psi | 78% | 2822 fps | 100% |
| Accurate 8700 | <<locked>> | 96% | 46,369 psi | 71% | 2841 fps | 95.9% |
| Accurate MAGPRO | <<locked>> | 80% | 52,866 psi | 81% | 2976 fps | 99.2% |
| ADI AR 2209 | <<locked>> | 80% | 54,534 psi | 84% | 2959 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 49,879 psi | 77% | 2910 fps | 99.5% |
| ADI AR 2217 | <<locked>> | 80% | 37,362 psi | 57% | 2648 fps | 97.2% |
| ADI AR 2218 | 79.4 gr | 88% | 42,888 psi | 66% | 2854 fps | 95.2% |
| ADI AR 2225 | <<locked>> | 80% | 34,722 psi | 53% | 2618 fps | 98.9% |
| Alliant Reloder-19 | <<locked>> | 80% | 54,288 psi | 84% | 2949 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 50,618 psi | 78% | 2910 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 49,371 psi | 76% | 2831 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 43,540 psi | 67% | 2782 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 86% | 44,541 psi | 69% | 2848 fps | 95.8% |
| Alliant Reloder-50 | 82.5 gr | 90% | 44,991 psi | 69% | 2844 fps | 95.2% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 47,166 psi | 73% | 2815 fps | 97% |
| Bofors RP15 | <<locked>> | 80% | 47,108 psi | 73% | 2841 fps | 99.6% |
| Bofors RP30 | <<locked>> | 80% | 40,727 psi | 63% | 2726 fps | 98.1% |
| Bofors RP5 | <<locked>> | 80% | 50,618 psi | 78% | 2910 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 80% | 40,741 psi | 63% | 2726 fps | 98.7% |
| Hodgdon H4831 | <<locked>> | 80% | 52,011 psi | 80% | 2904 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 80% | 51,213 psi | 79% | 2890 fps | 99.3% |
| Hodgdon Retumbo | <<locked>> | 80% | 42,685 psi | 66% | 2848 fps | 99.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,601 psi | 44% | 1732 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 52,330 psi | 81% | 2884 fps | 99.5% |
| IMR 7828 SSC | <<locked>> | 80% | 48,834 psi | 75% | 2897 fps | 99.4% |
| IMR 7977 Enduron | <<locked>> | 88% | 54,433 psi | 84% | 2894 fps | 95.5% |
| IMR 8133 Enduron | <<locked>> | 82% | 34,795 psi | 54% | 2598 fps | 95.9% |
| Lovex S071 | <<locked>> | 80% | 43,584 psi | 67% | 2697 fps | 100% |
| Norma 217 | <<locked>> | 80% | 32,880 psi | 51% | 2559 fps | 97.3% |
| Norma MRP | <<locked>> | 80% | 54,186 psi | 83% | 2982 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 49,632 psi | 76% | 2917 fps | 99.6% |
| Ramshot Magnum | <<locked>> | 80% | 44,788 psi | 69% | 2782 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,530 psi | 45% | 1778 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 42,453 psi | 65% | 2822 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 39,073 psi | 60% | 2710 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 54,708 psi | 84% | 2927 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 80% | 54,244 psi | 83% | 2943 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 94% | 45,150 psi | 69% | 2792 fps | 95% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 53,896 psi | 83% | 2940 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 54,331 psi | 84% | 2910 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 47,892 psi | 74% | 2789 fps | 99.9% |
| Vihtavuori N170 | <<locked>> | 84% | 47,253 psi | 73% | 2802 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 80% | 54,201 psi | 83% | 2907 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 53,490 psi | 82% | 2986 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 80% | 44,991 psi | 69% | 2802 fps | 98.5% |
| Vihtavuori N568 | <<locked>> | 80% | 40,089 psi | 62% | 2730 fps | 95.9% |
| Vihtavuori N570 | 74.3 gr | 84% | 44,309 psi | 68% | 2858 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 80% | 49,850 psi | 77% | 2910 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 50,415 psi | 78% | 2848 fps | 99.9% |
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 49 powders for 6.5-300 Weatherby Mag. loaded with the .264 | 140gr | Sierra MatchKing. ADI AR 2218 delivers the highest muzzle velocity at 3,159 fps; across all powders the maximum-charge window runs from 1,939 fps to 3,159 fps. Accurate 8700 gives the best case fill at 100 %, and 49 of the 49 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 140.0 gr projectile in 0.264" calls for a 1:9.5 twist; slower twists will usually not stabilise this weight. Accurate 8700, Hodgdon TrailBoss, ReloadSwiss RS 14 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 | 140gr | 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.