Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 140gr | Hornady ECX bullet and 52 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 Hodgdon Retumbo.
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>> | 86% | 58,450 psi | 90% | 2949 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 50,401 psi | 78% | 2923 fps | 96.9% |
| Accurate High Country | <<locked>> | 82% | 56,811 psi | 87% | 3051 fps | 99.9% |
| Accurate MAGPRO | <<locked>> | 84% | 57,885 psi | 89% | 3064 fps | 99.7% |
| ADI AR 2209 | <<locked>> | 82% | 55,825 psi | 86% | 2982 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 58,740 psi | 90% | 3061 fps | 100% |
| ADI AR 2217 | <<locked>> | 94% | 58,189 psi | 90% | 3048 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 54,404 psi | 84% | 3104 fps | 98.5% |
| ADI AR 2225 | <<locked>> | 96% | 57,624 psi | 89% | 3068 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 82% | 56,057 psi | 86% | 2979 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 55,492 psi | 85% | 2969 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 55,172 psi | 85% | 2992 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 57,058 psi | 88% | 2949 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 58,117 psi | 89% | 3035 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 58,160 psi | 90% | 3041 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 56,478 psi | 87% | 3077 fps | 98.5% |
| Alliant Reloder-50 | <<locked>> | 98% | 56,304 psi | 87% | 3068 fps | 98.1% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 58,726 psi | 90% | 3022 fps | 99% |
| Bofors RP15 | <<locked>> | 88% | 58,262 psi | 90% | 3038 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 57,682 psi | 89% | 3051 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 55,172 psi | 85% | 2992 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 55,390 psi | 85% | 3002 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 57,043 psi | 88% | 2989 fps | 99.8% |
| Hodgdon H4831 SC | <<locked>> | 84% | 56,101 psi | 86% | 2976 fps | 99.7% |
| Hodgdon Retumbo | <<locked>> | 90% | 57,928 psi | 89% | 3127 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,014 psi | 59% | 1929 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 57,276 psi | 88% | 2966 fps | 99.8% |
| IMR 7828 SSC | <<locked>> | 86% | 57,174 psi | 88% | 3045 fps | 100% |
| IMR 8133 Enduron | <<locked>> | 98% | 56,188 psi | 86% | 3041 fps | 100% |
| Lovex S071 | <<locked>> | 90% | 56,594 psi | 87% | 2920 fps | 100% |
| Norma 217 | <<locked>> | 98% | 57,870 psi | 89% | 3068 fps | 100% |
| Norma MRP | <<locked>> | 82% | 55,216 psi | 85% | 3002 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 54,462 psi | 84% | 3002 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 88% | 57,101 psi | 88% | 2995 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,972 psi | 60% | 1972 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 54,462 psi | 84% | 3048 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 57,667 psi | 89% | 3081 fps | 99.8% |
| Rottweil R 904 | <<locked>> | 82% | 56,043 psi | 86% | 2949 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 82% | 55,347 psi | 85% | 2966 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 52,214 psi | 80% | 2930 fps | 96.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 58,697 psi | 90% | 3018 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 57,392 psi | 88% | 2943 fps | 99.8% |
| Somchem S385 | <<locked>> | 82% | 55,361 psi | 85% | 2927 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 55,637 psi | 86% | 2923 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 54,795 psi | 84% | 2946 fps | 96.9% |
| Vihtavuori N555 | <<locked>> | 84% | 58,784 psi | 90% | 2982 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 58,711 psi | 90% | 3074 fps | 99.9% |
| Vihtavuori N565 | <<locked>> | 88% | 55,825 psi | 86% | 3009 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 92% | 58,102 psi | 89% | 3084 fps | 99.6% |
| Vihtavuori N570 | <<locked>> | 92% | 55,637 psi | 86% | 3087 fps | 98.1% |
| Winchester StaBALL HD | <<locked>> | 86% | 58,450 psi | 90% | 3045 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 55,216 psi | 85% | 2927 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% | 47,601 psi | 73% | 2776 fps | 100% |
| Accurate 8700 | <<locked>> | 98% | 46,557 psi | 72% | 2848 fps | 95.8% |
| Accurate High Country | <<locked>> | 80% | 52,968 psi | 82% | 2986 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 80% | 50,212 psi | 77% | 2930 fps | 98.8% |
| ADI AR 2209 | <<locked>> | 80% | 52,257 psi | 80% | 2920 fps | 99.9% |
| ADI AR 2213 | <<locked>> | 80% | 47,369 psi | 73% | 2864 fps | 99.1% |
| ADI AR 2217 | <<locked>> | 80% | 35,230 psi | 54% | 2595 fps | 96.2% |
| ADI AR 2218 | 79.2 gr | 90% | 43,323 psi | 67% | 2867 fps | 95.2% |
| ADI AR 2225 | <<locked>> | 80% | 32,503 psi | 50% | 2562 fps | 98.1% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 52,344 psi | 81% | 2917 fps | 99.9% |
| Alliant Reloder-19 | <<locked>> | 80% | 51,851 psi | 80% | 2910 fps | 99.9% |
| Alliant Reloder-22 | <<locked>> | 80% | 47,993 psi | 74% | 2864 fps | 99.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 46,847 psi | 72% | 2792 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 41,075 psi | 63% | 2740 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 53,911 psi | 83% | 2976 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 88% | 44,918 psi | 69% | 2858 fps | 95.7% |
| Alliant Reloder-50 | <<locked>> | 92% | 44,744 psi | 69% | 2841 fps | 95% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 45,078 psi | 69% | 2776 fps | 96.3% |
| Bofors RP15 | <<locked>> | 80% | 44,730 psi | 69% | 2799 fps | 99.3% |
| Bofors RP30 | <<locked>> | 80% | 38,087 psi | 59% | 2671 fps | 97.2% |
| Bofors RP5 | <<locked>> | 80% | 47,993 psi | 74% | 2864 fps | 99.7% |
| Hodgdon H1000 | <<locked>> | 80% | 38,508 psi | 59% | 2677 fps | 98% |
| Hodgdon H4831 | <<locked>> | 80% | 49,850 psi | 77% | 2864 fps | 99% |
| Hodgdon H4831 SC | <<locked>> | 80% | 48,805 psi | 75% | 2844 fps | 98.9% |
| Hodgdon Retumbo | 66.5 gr | 80% | 40,132 psi | 62% | 2795 fps | 99.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,500 psi | 44% | 1726 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 50,343 psi | 77% | 2848 fps | 99.2% |
| IMR 7828 SSC | <<locked>> | 80% | 46,238 psi | 71% | 2851 fps | 98.9% |
| IMR 8133 Enduron | <<locked>> | 84% | 34,577 psi | 53% | 2598 fps | 95.6% |
| Lovex S071 | <<locked>> | 80% | 40,930 psi | 63% | 2651 fps | 99.9% |
| Norma 217 | <<locked>> | 80% | 30,313 psi | 47% | 2493 fps | 95.9% |
| Norma MRP | <<locked>> | 80% | 51,459 psi | 79% | 2940 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 46,862 psi | 72% | 2867 fps | 99.2% |
| Ramshot Magnum | <<locked>> | 80% | 42,148 psi | 65% | 2733 fps | 99.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,240 psi | 45% | 1765 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 39,697 psi | 61% | 2769 fps | 99.7% |
| ReloadSwiss RS 80 | <<locked>> | 82% | 39,218 psi | 60% | 2720 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 52,576 psi | 81% | 2890 fps | 99.7% |
| Rottweil R 905 | <<locked>> | 80% | 51,605 psi | 79% | 2900 fps | 99.9% |
| SNPE Vectan SP 13 | <<locked>> | 98% | 48,660 psi | 75% | 2864 fps | 96% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 51,256 psi | 79% | 2897 fps | 99.9% |
| Somchem S361 | <<locked>> | 80% | 53,563 psi | 82% | 2881 fps | 99.5% |
| Somchem S385 | <<locked>> | 80% | 51,750 psi | 80% | 2867 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 45,455 psi | 70% | 2746 fps | 99.7% |
| Vihtavuori N170 | <<locked>> | 86% | 47,877 psi | 74% | 2818 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 80% | 51,459 psi | 79% | 2867 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 50,894 psi | 78% | 2943 fps | 99.2% |
| Vihtavuori N565 | <<locked>> | 80% | 42,293 psi | 65% | 2749 fps | 97.8% |
| Vihtavuori N568 | <<locked>> | 82% | 40,350 psi | 62% | 2743 fps | 95.8% |
| Vihtavuori N570 | 74.2 gr | 86% | 44,614 psi | 69% | 2871 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 80% | 46,586 psi | 72% | 2861 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 47,993 psi | 74% | 2805 fps | 99.7% |
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 52 powders for 6.5-300 Weatherby Mag. loaded with the .264 | 140gr | Hornady ECX. Hodgdon Retumbo delivers the highest muzzle velocity at 3,127 fps; across all powders the maximum-charge window runs from 1,929 fps to 3,127 fps. Accurate 8700 gives the best case fill at 100 %, and 52 of the 52 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 1:8.5 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, Hodgdon Retumbo rank at the top here: for 6.5-300 Weatherby Mag. with the .264 | 140gr | Hornady ECX 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.