Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 123gr | MRR Green Hunting bullet and 50 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ReloadSwiss RS 76 and ADI AR 2218.
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% | 56,260 psi | 87% | 3077 fps | 100% |
| Accurate High Country | <<locked>> | 84% | 58,291 psi | 90% | 3241 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 84% | 55,347 psi | 85% | 3179 fps | 98.7% |
| ADI AR 2209 | <<locked>> | 84% | 57,188 psi | 88% | 3169 fps | 99.9% |
| ADI AR 2213 | <<locked>> | 86% | 55,956 psi | 86% | 3182 fps | 99.5% |
| ADI AR 2217 | <<locked>> | 94% | 55,187 psi | 85% | 3163 fps | 99.7% |
| ADI AR 2218 | <<locked>> | 98% | 55,782 psi | 86% | 3274 fps | 97.7% |
| ADI AR 2225 | <<locked>> | 98% | 58,494 psi | 90% | 3248 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 56,797 psi | 87% | 3156 fps | 99.9% |
| Alliant Reloder-22 | <<locked>> | 86% | 56,463 psi | 87% | 3176 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 88% | 58,450 psi | 90% | 3143 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 55,245 psi | 85% | 3159 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 55,463 psi | 85% | 3169 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 57,856 psi | 89% | 3255 fps | 97.8% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 57,827 psi | 89% | 3241 fps | 97.3% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 56,376 psi | 87% | 3140 fps | 97.8% |
| Bofors RP15 | <<locked>> | 88% | 55,912 psi | 86% | 3166 fps | 99.9% |
| Bofors RP30 | <<locked>> | 92% | 55,114 psi | 85% | 3169 fps | 99.6% |
| Bofors RP5 | <<locked>> | 86% | 56,463 psi | 87% | 3176 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 92% | 56,579 psi | 87% | 3186 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 86% | 58,682 psi | 90% | 3176 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 86% | 57,551 psi | 89% | 3156 fps | 99.3% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 57,624 psi | 89% | 3074 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 92% | 58,755 psi | 90% | 3314 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,913 psi | 58% | 2054 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 86% | 58,653 psi | 90% | 3150 fps | 99.5% |
| IMR 7828 SSC | <<locked>> | 88% | 58,537 psi | 90% | 3232 fps | 99.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 57,348 psi | 88% | 3222 fps | 99.8% |
| Lovex S071 | <<locked>> | 92% | 58,305 psi | 90% | 3110 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 58,653 psi | 90% | 3245 fps | 100% |
| Norma MRP | <<locked>> | 84% | 56,608 psi | 87% | 3192 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 55,854 psi | 86% | 3189 fps | 99.7% |
| Ramshot Magnum | <<locked>> | 90% | 58,595 psi | 90% | 3182 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,827 psi | 60% | 2100 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 55,593 psi | 86% | 3232 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 54,824 psi | 84% | 3189 fps | 98.8% |
| Rottweil R 904 | <<locked>> | 84% | 57,580 psi | 89% | 3136 fps | 99.6% |
| Rottweil R 905 | <<locked>> | 84% | 56,739 psi | 87% | 3150 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 56,362 psi | 87% | 3146 fps | 99.9% |
| Somchem S361 | <<locked>> | 82% | 55,405 psi | 85% | 3068 fps | 99.1% |
| Somchem S385 | <<locked>> | 84% | 57,000 psi | 88% | 3117 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 57,043 psi | 88% | 3104 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 56,405 psi | 87% | 3120 fps | 96% |
| Vihtavuori N555 | <<locked>> | 84% | 56,420 psi | 87% | 3114 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 55,956 psi | 86% | 3192 fps | 99.2% |
| Vihtavuori N565 | <<locked>> | 90% | 57,290 psi | 88% | 3189 fps | 99.5% |
| Vihtavuori N568 | <<locked>> | 92% | 55,332 psi | 85% | 3196 fps | 98.5% |
| Vihtavuori N570 | <<locked>> | 94% | 56,608 psi | 87% | 3258 fps | 97.2% |
| Winchester StaBALL HD | <<locked>> | 86% | 55,245 psi | 85% | 3173 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 56,913 psi | 88% | 3114 fps | 99.9% |
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% | 46,006 psi | 71% | 2900 fps | 99.9% |
| Accurate High Country | <<locked>> | 80% | 50,749 psi | 78% | 3104 fps | 98.8% |
| Accurate MAGPRO | <<locked>> | 80% | 48,008 psi | 74% | 3035 fps | 97.3% |
| ADI AR 2209 | <<locked>> | 80% | 50,154 psi | 77% | 3041 fps | 99.4% |
| ADI AR 2213 | <<locked>> | 80% | 45,397 psi | 70% | 2976 fps | 97.7% |
| ADI AR 2217 | <<locked>> | 82% | 36,289 psi | 56% | 2756 fps | 95% |
| ADI AR 2218 | 85.2 gr | 94% | 48,080 psi | 74% | 3110 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 80% | 31,154 psi | 48% | 2648 fps | 95.8% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,850 psi | 77% | 3028 fps | 99.3% |
| Alliant Reloder-22 | <<locked>> | 80% | 46,180 psi | 71% | 2982 fps | 98.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,962 psi | 69% | 2917 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 39,117 psi | 60% | 2848 fps | 99.7% |
| Alliant Reloder-26 | <<locked>> | 80% | 51,300 psi | 79% | 3100 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 49,719 psi | 77% | 3100 fps | 95.8% |
| Alliant Reloder-50 | <<locked>> | 96% | 49,661 psi | 76% | 3087 fps | 95.2% |
| Baschieri & Pellagri 109 | <<locked>> | 82% | 46,296 psi | 71% | 2943 fps | 95.3% |
| Bofors RP15 | <<locked>> | 80% | 42,931 psi | 66% | 2910 fps | 98% |
| Bofors RP30 | <<locked>> | 80% | 36,463 psi | 56% | 2769 fps | 95.2% |
| Bofors RP5 | <<locked>> | 80% | 46,180 psi | 71% | 2982 fps | 98.9% |
| Hodgdon H1000 | <<locked>> | 80% | 36,811 psi | 57% | 2772 fps | 96% |
| Hodgdon H4831 | <<locked>> | 80% | 47,805 psi | 74% | 2976 fps | 97.7% |
| Hodgdon H4831 SC | <<locked>> | 80% | 47,050 psi | 72% | 2959 fps | 97.6% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,896 psi | 83% | 3018 fps | 100% |
| Hodgdon Retumbo | 68.4 gr | 80% | 38,145 psi | 59% | 2890 fps | 97.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,384 psi | 44% | 1837 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,588 psi | 75% | 2966 fps | 98.1% |
| IMR 7828 SSC | <<locked>> | 80% | 44,077 psi | 68% | 2956 fps | 97.4% |
| IMR 8133 Enduron | <<locked>> | 88% | 38,000 psi | 58% | 2825 fps | 95.6% |
| Lovex S071 | <<locked>> | 80% | 39,639 psi | 61% | 2766 fps | 99.2% |
| Norma 217 | <<locked>> | 84% | 33,388 psi | 51% | 2713 fps | 96% |
| Norma MRP | <<locked>> | 80% | 49,240 psi | 76% | 3058 fps | 99.8% |
| Ramshot Grand | <<locked>> | 80% | 44,556 psi | 69% | 2972 fps | 97.9% |
| Ramshot Magnum | <<locked>> | 80% | 40,190 psi | 62% | 2835 fps | 98.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,240 psi | 45% | 1883 fps | 100% |
| ReloadSwiss RS 76 | 73.2 gr | 80% | 37,637 psi | 58% | 2864 fps | 98.5% |
| ReloadSwiss RS 80 | <<locked>> | 86% | 43,540 psi | 67% | 2963 fps | 96.1% |
| Rottweil R 904 | <<locked>> | 80% | 50,676 psi | 78% | 3015 fps | 98.8% |
| Rottweil R 905 | <<locked>> | 80% | 49,632 psi | 76% | 3022 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 49,284 psi | 76% | 3018 fps | 99.3% |
| Somchem S361 | <<locked>> | 80% | 51,851 psi | 80% | 3002 fps | 98.6% |
| Somchem S385 | <<locked>> | 80% | 50,067 psi | 77% | 2995 fps | 99.8% |
| Vihtavuori N165 | <<locked>> | 80% | 43,758 psi | 67% | 2861 fps | 98.8% |
| Vihtavuori N170 | <<locked>> | 90% | 52,866 psi | 81% | 3058 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 80% | 49,603 psi | 76% | 2999 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 48,762 psi | 75% | 3054 fps | 98% |
| Vihtavuori N565 | <<locked>> | 80% | 40,741 psi | 63% | 2854 fps | 96% |
| Vihtavuori N568 | <<locked>> | 86% | 44,498 psi | 68% | 2976 fps | 95.8% |
| Vihtavuori N570 | <<locked>> | 90% | 49,052 psi | 75% | 3110 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 80% | 44,077 psi | 68% | 2982 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 46,282 psi | 71% | 2920 fps | 98.9% |
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 50 powders for 6.5-300 Weatherby Mag. loaded with the .264 | 123gr | MRR Green Hunting. Hodgdon Retumbo delivers the highest muzzle velocity at 3,314 fps; across all powders the maximum-charge window runs from 2,054 fps to 3,314 fps. Alliant Reloder-50 gives the best case fill at 100 %, and 50 of the 50 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 123.0 gr projectile in 0.264" calls for a 1:9.5 twist; slower twists will usually not stabilise this weight. Alliant Reloder-50, Hodgdon TrailBoss, IMR 8133 Enduron 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. Hodgdon Retumbo, ReloadSwiss RS 76, ADI AR 2218 rank at the top here: for 6.5-300 Weatherby Mag. with the .264 | 123gr | MRR Green Hunting 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.