Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 125gr | Nosler Partition 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, ADI AR 2218 and Vihtavuori N570.
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% | 57,769 psi | 89% | 3081 fps | 100% |
| Accurate High Country | <<locked>> | 82% | 55,840 psi | 86% | 3179 fps | 99.6% |
| Accurate MAGPRO | <<locked>> | 84% | 56,840 psi | 87% | 3182 fps | 99.1% |
| ADI AR 2209 | <<locked>> | 84% | 58,697 psi | 90% | 3173 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 57,464 psi | 88% | 3186 fps | 99.7% |
| ADI AR 2217 | <<locked>> | 94% | 56,768 psi | 87% | 3166 fps | 99.9% |
| ADI AR 2218 | <<locked>> | 98% | 57,464 psi | 88% | 3287 fps | 98.2% |
| ADI AR 2225 | <<locked>> | 96% | 56,159 psi | 86% | 3189 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 58,044 psi | 89% | 3153 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 57,986 psi | 89% | 3179 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 56,246 psi | 87% | 3084 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 56,884 psi | 88% | 3159 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 56,913 psi | 88% | 3166 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 55,317 psi | 85% | 3186 fps | 97.5% |
| Alliant Reloder-50 | <<locked>> | 98% | 55,477 psi | 85% | 3179 fps | 97% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 57,595 psi | 89% | 3136 fps | 98.2% |
| Bofors RP15 | <<locked>> | 88% | 57,392 psi | 88% | 3169 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 56,623 psi | 87% | 3173 fps | 99.8% |
| Bofors RP5 | <<locked>> | 86% | 57,986 psi | 89% | 3179 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 58,204 psi | 90% | 3186 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 56,086 psi | 86% | 3110 fps | 99.3% |
| Hodgdon H4831 SC | <<locked>> | 84% | 54,998 psi | 85% | 3094 fps | 99.1% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 58,682 psi | 90% | 3068 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 56,260 psi | 87% | 3248 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,942 psi | 58% | 2044 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 56,333 psi | 87% | 3091 fps | 99.4% |
| IMR 7828 SSC | <<locked>> | 86% | 55,985 psi | 86% | 3166 fps | 99.6% |
| IMR 8133 Enduron | <<locked>> | 98% | 55,274 psi | 85% | 3163 fps | 99.7% |
| Lovex S071 | <<locked>> | 90% | 56,028 psi | 86% | 3051 fps | 100% |
| Norma 217 | <<locked>> | 98% | 56,579 psi | 87% | 3189 fps | 100% |
| Norma MRP | <<locked>> | 84% | 58,218 psi | 90% | 3192 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 57,319 psi | 88% | 3192 fps | 99.8% |
| Ramshot Magnum | <<locked>> | 88% | 55,912 psi | 86% | 3117 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,856 psi | 60% | 2087 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 57,348 psi | 88% | 3235 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 56,420 psi | 87% | 3196 fps | 99.2% |
| Rottweil R 904 | <<locked>> | 84% | 58,769 psi | 90% | 3133 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 84% | 58,030 psi | 89% | 3150 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 57,653 psi | 89% | 3146 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 56,463 psi | 87% | 3064 fps | 99.3% |
| Somchem S385 | <<locked>> | 84% | 58,218 psi | 90% | 3114 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 58,436 psi | 90% | 3104 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 57,943 psi | 89% | 3130 fps | 96.6% |
| Vihtavuori N555 | <<locked>> | 84% | 57,783 psi | 89% | 3114 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 57,479 psi | 88% | 3199 fps | 99.5% |
| Vihtavuori N565 | <<locked>> | 90% | 58,784 psi | 90% | 3192 fps | 99.7% |
| Vihtavuori N568 | <<locked>> | 92% | 56,855 psi | 88% | 3199 fps | 98.9% |
| Vihtavuori N570 | <<locked>> | 94% | 58,450 psi | 90% | 3268 fps | 97.7% |
| Winchester StaBALL HD | <<locked>> | 86% | 57,072 psi | 88% | 3173 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 58,320 psi | 90% | 3114 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% | 47,166 psi | 73% | 2900 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 52,040 psi | 80% | 3104 fps | 99.1% |
| Accurate MAGPRO | <<locked>> | 80% | 49,240 psi | 76% | 3041 fps | 97.7% |
| ADI AR 2209 | <<locked>> | 80% | 51,169 psi | 79% | 3041 fps | 99.6% |
| ADI AR 2213 | <<locked>> | 80% | 46,615 psi | 72% | 2982 fps | 98.2% |
| ADI AR 2217 | <<locked>> | 82% | 37,275 psi | 57% | 2766 fps | 95.8% |
| ADI AR 2218 | 86.1 gr | 94% | 49,385 psi | 76% | 3123 fps | 96.1% |
| ADI AR 2225 | <<locked>> | 80% | 32,097 psi | 49% | 2657 fps | 96.6% |
| Alliant Reloder-19 | <<locked>> | 80% | 50,995 psi | 78% | 3031 fps | 99.6% |
| Alliant Reloder-22 | <<locked>> | 80% | 47,384 psi | 73% | 2986 fps | 99.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 46,021 psi | 71% | 2913 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 40,147 psi | 62% | 2848 fps | 99.8% |
| Alliant Reloder-26 | <<locked>> | 80% | 52,924 psi | 81% | 3100 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 47,616 psi | 73% | 3038 fps | 95.4% |
| Alliant Reloder-50 | <<locked>> | 96% | 51,358 psi | 79% | 3100 fps | 95.9% |
| Baschieri & Pellagri 109 | <<locked>> | 82% | 47,442 psi | 73% | 2949 fps | 95.9% |
| Bofors RP15 | <<locked>> | 80% | 44,077 psi | 68% | 2917 fps | 98.5% |
| Bofors RP30 | <<locked>> | 80% | 37,579 psi | 58% | 2776 fps | 95.9% |
| Bofors RP5 | <<locked>> | 80% | 47,384 psi | 73% | 2986 fps | 99.2% |
| Hodgdon H1000 | <<locked>> | 80% | 37,855 psi | 58% | 2782 fps | 96.7% |
| Hodgdon H4831 | <<locked>> | 80% | 48,907 psi | 75% | 2979 fps | 98.1% |
| Hodgdon H4831 SC | <<locked>> | 80% | 48,167 psi | 74% | 2966 fps | 98% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 55,158 psi | 85% | 3015 fps | 100% |
| Hodgdon Retumbo | 69.2 gr | 80% | 39,349 psi | 61% | 2900 fps | 98.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,500 psi | 44% | 1831 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 49,458 psi | 76% | 2966 fps | 98.4% |
| IMR 7828 SSC | <<locked>> | 80% | 45,324 psi | 70% | 2963 fps | 97.9% |
| IMR 8133 Enduron | <<locked>> | 86% | 36,622 psi | 56% | 2766 fps | 95.2% |
| Lovex S071 | <<locked>> | 80% | 40,727 psi | 63% | 2769 fps | 99.5% |
| Norma 217 | <<locked>> | 82% | 32,256 psi | 50% | 2661 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 50,531 psi | 78% | 3061 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 45,876 psi | 71% | 2979 fps | 98.4% |
| Ramshot Magnum | <<locked>> | 80% | 41,365 psi | 64% | 2841 fps | 98.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,211 psi | 45% | 1870 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 38,798 psi | 60% | 2871 fps | 99% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 41,756 psi | 64% | 2897 fps | 95.7% |
| Rottweil R 904 | <<locked>> | 80% | 51,619 psi | 79% | 3012 fps | 99.1% |
| Rottweil R 905 | <<locked>> | 80% | 50,836 psi | 78% | 3025 fps | 99.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 50,488 psi | 78% | 3018 fps | 99.6% |
| Somchem S361 | <<locked>> | 80% | 52,866 psi | 81% | 3002 fps | 98.9% |
| Somchem S385 | <<locked>> | 80% | 51,242 psi | 79% | 2995 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 80% | 44,846 psi | 69% | 2864 fps | 99.1% |
| Vihtavuori N170 | <<locked>> | 90% | 54,143 psi | 83% | 3061 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 80% | 50,865 psi | 78% | 3002 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 49,980 psi | 77% | 3058 fps | 98.4% |
| Vihtavuori N565 | <<locked>> | 80% | 41,829 psi | 64% | 2861 fps | 96.6% |
| Vihtavuori N568 | <<locked>> | 84% | 42,685 psi | 66% | 2913 fps | 95.4% |
| Vihtavuori N570 | 80.8 gr | 90% | 50,589 psi | 78% | 3120 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 45,585 psi | 70% | 2986 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 47,355 psi | 73% | 2923 fps | 99.2% |
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 | 125gr | Nosler Partition. ADI AR 2218 delivers the highest muzzle velocity at 3,287 fps; across all powders the maximum-charge window runs from 2,044 fps to 3,287 fps. Hodgdon TrailBoss 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 125.0 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 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, ADI AR 2218, Vihtavuori N570 rank at the top here: for 6.5-300 Weatherby Mag. with the .264 | 125gr | Nosler Partition 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.