Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 125gr | Hammer HHT bullet and 52 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N570, Hodgdon Retumbo and ReloadSwiss RS 76.
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% | 55,666 psi | 86% | 3051 fps | 100% |
| Accurate High Country | <<locked>> | 84% | 57,638 psi | 89% | 3212 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 84% | 54,766 psi | 84% | 3150 fps | 98.7% |
| ADI AR 2209 | <<locked>> | 84% | 56,753 psi | 87% | 3143 fps | 99.9% |
| ADI AR 2213 | <<locked>> | 86% | 55,347 psi | 85% | 3153 fps | 99.5% |
| ADI AR 2217 | <<locked>> | 96% | 58,363 psi | 90% | 3199 fps | 99.9% |
| ADI AR 2218 | <<locked>> | 98% | 54,984 psi | 85% | 3241 fps | 97.5% |
| ADI AR 2225 | <<locked>> | 98% | 57,609 psi | 89% | 3219 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 56,985 psi | 88% | 3136 fps | 99.9% |
| Alliant Reloder-19 | <<locked>> | 84% | 56,391 psi | 87% | 3130 fps | 99.9% |
| Alliant Reloder-22 | <<locked>> | 86% | 55,869 psi | 86% | 3146 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 88% | 57,783 psi | 89% | 3110 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 92% | 58,392 psi | 90% | 3189 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 54,592 psi | 84% | 3140 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 56,971 psi | 88% | 3225 fps | 97.7% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 56,753 psi | 87% | 3209 fps | 97.2% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 55,825 psi | 86% | 3110 fps | 97.8% |
| Bofors RP15 | <<locked>> | 88% | 55,332 psi | 85% | 3140 fps | 99.9% |
| Bofors RP30 | <<locked>> | 94% | 58,247 psi | 90% | 3205 fps | 99.9% |
| Bofors RP5 | <<locked>> | 86% | 55,869 psi | 86% | 3146 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 92% | 55,883 psi | 86% | 3156 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 86% | 58,117 psi | 89% | 3150 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 86% | 56,971 psi | 88% | 3127 fps | 99.3% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 57,014 psi | 88% | 3048 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 92% | 57,928 psi | 89% | 3284 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,869 psi | 58% | 2034 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 58,610 psi | 90% | 3114 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 86% | 58,305 psi | 90% | 3127 fps | 99.5% |
| IMR 7828 SSC | <<locked>> | 88% | 57,711 psi | 89% | 3199 fps | 99.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 56,507 psi | 87% | 3192 fps | 99.8% |
| Lovex S071 | <<locked>> | 92% | 57,725 psi | 89% | 3084 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 57,783 psi | 89% | 3219 fps | 100% |
| Norma MRP | <<locked>> | 84% | 56,014 psi | 86% | 3163 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 55,027 psi | 85% | 3156 fps | 99.6% |
| Ramshot Magnum | <<locked>> | 90% | 57,725 psi | 89% | 3146 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,783 psi | 60% | 2077 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 54,650 psi | 84% | 3202 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 58,291 psi | 90% | 3235 fps | 99.3% |
| Rottweil R 904 | <<locked>> | 84% | 57,159 psi | 88% | 3110 fps | 99.6% |
| Rottweil R 905 | <<locked>> | 84% | 56,057 psi | 86% | 3117 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 55,680 psi | 86% | 3117 fps | 99.9% |
| Somchem S361 | <<locked>> | 84% | 58,537 psi | 90% | 3097 fps | 99.4% |
| Somchem S385 | <<locked>> | 84% | 56,376 psi | 87% | 3087 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 56,492 psi | 87% | 3074 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 55,883 psi | 86% | 3094 fps | 96% |
| Vihtavuori N555 | <<locked>> | 84% | 55,898 psi | 86% | 3087 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 55,390 psi | 85% | 3163 fps | 99.2% |
| Vihtavuori N565 | <<locked>> | 90% | 56,608 psi | 87% | 3159 fps | 99.5% |
| Vihtavuori N568 | <<locked>> | 94% | 58,407 psi | 90% | 3232 fps | 99% |
| Vihtavuori N570 | <<locked>> | 94% | 55,782 psi | 86% | 3228 fps | 97.1% |
| Winchester StaBALL HD | <<locked>> | 88% | 58,668 psi | 90% | 3205 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 56,362 psi | 87% | 3087 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% | 45,484 psi | 70% | 2874 fps | 99.9% |
| Accurate High Country | <<locked>> | 80% | 50,082 psi | 77% | 3074 fps | 98.8% |
| Accurate MAGPRO | <<locked>> | 80% | 47,398 psi | 73% | 3009 fps | 97.2% |
| ADI AR 2209 | <<locked>> | 80% | 49,661 psi | 76% | 3012 fps | 99.4% |
| ADI AR 2213 | <<locked>> | 80% | 44,904 psi | 69% | 2949 fps | 97.7% |
| ADI AR 2217 | <<locked>> | 82% | 35,897 psi | 55% | 2733 fps | 95% |
| ADI AR 2218 | <<locked>> | 94% | 47,282 psi | 73% | 3081 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 80% | 30,806 psi | 47% | 2625 fps | 95.8% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 49,806 psi | 77% | 3009 fps | 99.4% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,371 psi | 76% | 3002 fps | 99.3% |
| Alliant Reloder-22 | <<locked>> | 80% | 45,687 psi | 70% | 2956 fps | 98.8% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,396 psi | 68% | 2890 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 38,624 psi | 59% | 2822 fps | 99.6% |
| Alliant Reloder-26 | <<locked>> | 80% | 50,618 psi | 78% | 3071 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 48,805 psi | 75% | 3071 fps | 95.7% |
| Alliant Reloder-50 | <<locked>> | 96% | 48,820 psi | 75% | 3058 fps | 95% |
| Baschieri & Pellagri 109 | <<locked>> | 82% | 45,832 psi | 71% | 2917 fps | 95.2% |
| Bofors RP15 | <<locked>> | 80% | 42,424 psi | 65% | 2884 fps | 98% |
| Bofors RP30 | <<locked>> | 80% | 35,969 psi | 55% | 2743 fps | 95.1% |
| Bofors RP5 | <<locked>> | 80% | 45,687 psi | 70% | 2956 fps | 98.8% |
| Hodgdon H1000 | <<locked>> | 80% | 36,390 psi | 56% | 2749 fps | 96% |
| Hodgdon H4831 | <<locked>> | 80% | 47,340 psi | 73% | 2949 fps | 97.7% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,586 psi | 72% | 2933 fps | 97.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,490 psi | 82% | 2995 fps | 100% |
| Hodgdon Retumbo | 67 gr | 80% | 37,681 psi | 58% | 2861 fps | 97.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,471 psi | 44% | 1821 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 55,158 psi | 85% | 3058 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,138 psi | 74% | 2940 fps | 98.1% |
| IMR 7828 SSC | <<locked>> | 80% | 43,584 psi | 67% | 2930 fps | 97.4% |
| IMR 8133 Enduron | <<locked>> | 88% | 37,449 psi | 58% | 2795 fps | 95.5% |
| Lovex S071 | <<locked>> | 80% | 39,233 psi | 60% | 2740 fps | 99.2% |
| Norma 217 | <<locked>> | 84% | 32,909 psi | 51% | 2690 fps | 95.9% |
| Norma MRP | <<locked>> | 80% | 48,559 psi | 75% | 3031 fps | 99.8% |
| Ramshot Grand | <<locked>> | 80% | 44,063 psi | 68% | 2946 fps | 97.9% |
| Ramshot Magnum | <<locked>> | 80% | 39,624 psi | 61% | 2808 fps | 98.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,182 psi | 45% | 1864 fps | 100% |
| ReloadSwiss RS 76 | 71.7 gr | 80% | 37,101 psi | 57% | 2835 fps | 98.4% |
| ReloadSwiss RS 80 | <<locked>> | 86% | 42,888 psi | 66% | 2933 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 50,183 psi | 77% | 2986 fps | 98.8% |
| Rottweil R 905 | <<locked>> | 80% | 49,066 psi | 76% | 2992 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 48,718 psi | 75% | 2989 fps | 99.3% |
| Somchem S361 | <<locked>> | 80% | 51,314 psi | 79% | 2976 fps | 98.5% |
| Somchem S385 | <<locked>> | 80% | 49,588 psi | 76% | 2969 fps | 99.8% |
| Vihtavuori N165 | <<locked>> | 80% | 43,279 psi | 67% | 2835 fps | 98.8% |
| Vihtavuori N170 | <<locked>> | 90% | 52,112 psi | 80% | 3025 fps | 95% |
| Vihtavuori N555 | <<locked>> | 80% | 49,008 psi | 75% | 2972 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 48,109 psi | 74% | 3025 fps | 98% |
| Vihtavuori N565 | <<locked>> | 80% | 40,277 psi | 62% | 2828 fps | 96% |
| Vihtavuori N568 | <<locked>> | 86% | 44,005 psi | 68% | 2953 fps | 95.8% |
| Vihtavuori N570 | 78.2 gr | 90% | 48,196 psi | 74% | 3077 fps | 95% |
| Winchester StaBALL HD | <<locked>> | 80% | 43,294 psi | 67% | 2953 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 45,818 psi | 71% | 2894 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 52 powders for 6.5-300 Weatherby Mag. loaded with the .264 | 125gr | Hammer HHT. Hodgdon Retumbo delivers the highest muzzle velocity at 3,284 fps; across all powders the maximum-charge window runs from 2,034 fps to 3,284 fps. Alliant Reloder-50 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 58–90 %, leaving at least 10 % headroom. The 125.0 gr projectile in 0.264" calls for a 1:8.0 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. Vihtavuori N570, Hodgdon Retumbo, ReloadSwiss RS 76 rank at the top here: for 6.5-300 Weatherby Mag. with the .264 | 125gr | Hammer HHT 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.