Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 142gr | 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% | 57,479 psi | 88% | 2913 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 53,432 psi | 82% | 2956 fps | 97.8% |
| Accurate MAGPRO | <<locked>> | 82% | 56,565 psi | 87% | 3022 fps | 99.7% |
| ADI AR 2209 | <<locked>> | 82% | 58,059 psi | 89% | 2995 fps | 100% |
| ADI AR 2213 | <<locked>> | 84% | 57,072 psi | 88% | 3015 fps | 100% |
| ADI AR 2217 | <<locked>> | 92% | 56,768 psi | 87% | 3005 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 57,392 psi | 88% | 3140 fps | 99.2% |
| ADI AR 2225 | <<locked>> | 94% | 56,782 psi | 87% | 3031 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 57,725 psi | 89% | 2986 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 57,638 psi | 89% | 3009 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 84% | 55,999 psi | 86% | 2913 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 88% | 56,985 psi | 88% | 2992 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 55,521 psi | 85% | 3045 fps | 98.6% |
| Alliant Reloder-50 | <<locked>> | 96% | 55,898 psi | 86% | 3041 fps | 98.2% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 57,159 psi | 88% | 2979 fps | 99% |
| Bofors RP15 | <<locked>> | 86% | 57,276 psi | 88% | 3002 fps | 100% |
| Bofors RP30 | <<locked>> | 90% | 56,898 psi | 88% | 3018 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 57,638 psi | 89% | 3009 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 58,146 psi | 89% | 3025 fps | 100% |
| Hodgdon H4831 | <<locked>> | 82% | 55,608 psi | 86% | 2946 fps | 99.7% |
| Hodgdon H4831 SC | <<locked>> | 84% | 58,320 psi | 90% | 2989 fps | 99.9% |
| Hodgdon Retumbo | <<locked>> | 88% | 56,855 psi | 88% | 3091 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,130 psi | 59% | 1923 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 55,593 psi | 86% | 2920 fps | 99.8% |
| IMR 7828 SSC | <<locked>> | 84% | 55,912 psi | 86% | 3005 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 90% | 58,030 psi | 89% | 2940 fps | 96.4% |
| IMR 8133 Enduron | <<locked>> | 96% | 55,709 psi | 86% | 3015 fps | 100% |
| Lovex S071 | <<locked>> | 88% | 55,912 psi | 86% | 2890 fps | 100% |
| Norma 217 | <<locked>> | 96% | 57,232 psi | 88% | 3038 fps | 100% |
| Norma MRP | <<locked>> | 82% | 58,030 psi | 89% | 3025 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 57,363 psi | 88% | 3028 fps | 100% |
| Ramshot Magnum | <<locked>> | 86% | 55,709 psi | 86% | 2953 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,117 psi | 60% | 1965 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 57,595 psi | 89% | 3074 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 56,724 psi | 87% | 3045 fps | 99.8% |
| Rottweil R 904 | <<locked>> | 82% | 58,175 psi | 90% | 2966 fps | 100% |
| Rottweil R 905 | <<locked>> | 82% | 57,711 psi | 89% | 2979 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 55,201 psi | 85% | 2966 fps | 97.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 57,348 psi | 88% | 2976 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 57,769 psi | 89% | 2946 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 57,943 psi | 89% | 2936 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 57,609 psi | 89% | 2976 fps | 97.7% |
| Vihtavuori N555 | <<locked>> | 82% | 57,856 psi | 89% | 2946 fps | 100% |
| Vihtavuori N560 | <<locked>> | 82% | 57,232 psi | 88% | 3031 fps | 99.9% |
| Vihtavuori N565 | <<locked>> | 88% | 58,711 psi | 90% | 3031 fps | 100% |
| Vihtavuori N568 | <<locked>> | 90% | 57,058 psi | 88% | 3051 fps | 99.6% |
| Vihtavuori N570 | <<locked>> | 92% | 58,624 psi | 90% | 3117 fps | 98.8% |
| Winchester StaBALL HD | <<locked>> | 84% | 57,624 psi | 89% | 3012 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 57,754 psi | 89% | 2946 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% | 50,212 psi | 77% | 2802 fps | 100% |
| Accurate 8700 | <<locked>> | 96% | 46,050 psi | 71% | 2822 fps | 95.9% |
| Accurate MAGPRO | <<locked>> | 80% | 52,692 psi | 81% | 2956 fps | 99.3% |
| ADI AR 2209 | <<locked>> | 80% | 54,491 psi | 84% | 2940 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 49,850 psi | 77% | 2894 fps | 99.5% |
| ADI AR 2217 | <<locked>> | 80% | 37,333 psi | 57% | 2631 fps | 97.3% |
| ADI AR 2218 | 78.4 gr | 88% | 42,685 psi | 66% | 2835 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 80% | 34,679 psi | 53% | 2602 fps | 99% |
| Alliant Reloder-19 | <<locked>> | 80% | 54,056 psi | 83% | 2927 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 50,575 psi | 78% | 2894 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 49,284 psi | 76% | 2808 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 43,482 psi | 67% | 2769 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 86% | 44,353 psi | 68% | 2828 fps | 95.8% |
| Alliant Reloder-50 | 81.4 gr | 90% | 44,657 psi | 69% | 2825 fps | 95.3% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 47,050 psi | 72% | 2799 fps | 97.1% |
| Bofors RP15 | <<locked>> | 80% | 47,036 psi | 72% | 2825 fps | 99.7% |
| Bofors RP30 | <<locked>> | 80% | 40,524 psi | 62% | 2710 fps | 98.2% |
| Bofors RP5 | <<locked>> | 80% | 50,575 psi | 78% | 2894 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 80% | 40,741 psi | 63% | 2710 fps | 98.8% |
| Hodgdon H4831 | <<locked>> | 80% | 51,996 psi | 80% | 2884 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 80% | 51,184 psi | 79% | 2871 fps | 99.3% |
| Hodgdon Retumbo | <<locked>> | 80% | 42,656 psi | 66% | 2831 fps | 99.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,747 psi | 44% | 1719 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 52,315 psi | 81% | 2867 fps | 99.6% |
| IMR 7828 SSC | <<locked>> | 80% | 48,588 psi | 75% | 2877 fps | 99.4% |
| IMR 7977 Enduron | <<locked>> | 88% | 54,317 psi | 84% | 2877 fps | 95.6% |
| IMR 8133 Enduron | <<locked>> | 82% | 34,592 psi | 53% | 2579 fps | 95.9% |
| Lovex S071 | <<locked>> | 80% | 43,482 psi | 67% | 2680 fps | 100% |
| Norma 217 | <<locked>> | 80% | 32,808 psi | 50% | 2546 fps | 97.4% |
| Norma MRP | <<locked>> | 80% | 54,012 psi | 83% | 2963 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 49,647 psi | 76% | 2900 fps | 99.7% |
| Ramshot Magnum | <<locked>> | 80% | 44,614 psi | 69% | 2766 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,515 psi | 45% | 1762 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 42,308 psi | 65% | 2808 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 38,957 psi | 60% | 2694 fps | 96.1% |
| Rottweil R 904 | <<locked>> | 80% | 54,694 psi | 84% | 2910 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 80% | 53,954 psi | 83% | 2920 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 94% | 44,831 psi | 69% | 2772 fps | 95% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 53,650 psi | 83% | 2917 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 54,346 psi | 84% | 2894 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 47,659 psi | 73% | 2769 fps | 99.9% |
| Vihtavuori N170 | <<locked>> | 84% | 46,992 psi | 72% | 2782 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 80% | 54,114 psi | 83% | 2887 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 53,330 psi | 82% | 2966 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 80% | 44,802 psi | 69% | 2782 fps | 98.6% |
| Vihtavuori N568 | <<locked>> | 80% | 39,943 psi | 61% | 2713 fps | 96% |
| Vihtavuori N570 | 73.3 gr | 84% | 43,990 psi | 68% | 2835 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 80% | 49,574 psi | 76% | 2887 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 50,415 psi | 78% | 2828 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 | 142gr | Sierra MatchKing. ADI AR 2218 delivers the highest muzzle velocity at 3,140 fps; across all powders the maximum-charge window runs from 1,923 fps to 3,140 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 142.0 gr projectile in 0.264" calls for a 1:8.5 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 | 142gr | 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.