Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 129gr | Hornady InterLock bullet and 51 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>> | 84% | 55,129 psi | 85% | 3002 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 50,531 psi | 78% | 3009 fps | 96.1% |
| Accurate High Country | <<locked>> | 82% | 56,971 psi | 88% | 3156 fps | 99.8% |
| Accurate MAGPRO | <<locked>> | 84% | 58,030 psi | 89% | 3166 fps | 99.4% |
| ADI AR 2209 | <<locked>> | 82% | 55,912 psi | 86% | 3087 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 58,639 psi | 90% | 3163 fps | 99.9% |
| ADI AR 2217 | <<locked>> | 94% | 58,088 psi | 89% | 3146 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 54,505 psi | 84% | 3196 fps | 97.9% |
| ADI AR 2225 | <<locked>> | 96% | 57,624 psi | 89% | 3166 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 55,376 psi | 85% | 3071 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 55,172 psi | 85% | 3091 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 57,348 psi | 88% | 3061 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 58,146 psi | 89% | 3136 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 58,204 psi | 90% | 3143 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 56,739 psi | 87% | 3179 fps | 98.1% |
| Alliant Reloder-50 | <<locked>> | 98% | 56,797 psi | 87% | 3166 fps | 97.6% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 58,610 psi | 90% | 3120 fps | 98.6% |
| Bofors RP15 | <<locked>> | 88% | 58,523 psi | 90% | 3150 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 57,899 psi | 89% | 3153 fps | 99.9% |
| Bofors RP5 | <<locked>> | 84% | 55,172 psi | 85% | 3091 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 55,535 psi | 85% | 3107 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 57,116 psi | 88% | 3091 fps | 99.5% |
| Hodgdon H4831 SC | <<locked>> | 84% | 56,014 psi | 86% | 3071 fps | 99.4% |
| Hodgdon Retumbo | <<locked>> | 90% | 57,725 psi | 89% | 3228 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,956 psi | 58% | 2014 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 57,217 psi | 88% | 3064 fps | 99.6% |
| IMR 7828 SSC | <<locked>> | 86% | 57,145 psi | 88% | 3146 fps | 99.8% |
| IMR 8133 Enduron | <<locked>> | 98% | 56,391 psi | 87% | 3143 fps | 99.9% |
| Lovex S071 | <<locked>> | 90% | 57,072 psi | 88% | 3028 fps | 100% |
| Norma 217 | <<locked>> | 98% | 58,073 psi | 89% | 3169 fps | 100% |
| Norma MRP | <<locked>> | 82% | 55,390 psi | 85% | 3107 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 58,639 psi | 90% | 3169 fps | 100% |
| Ramshot Magnum | <<locked>> | 88% | 57,217 psi | 88% | 3097 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,059 psi | 60% | 2060 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 54,418 psi | 84% | 3146 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 57,899 psi | 89% | 3182 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 82% | 56,202 psi | 86% | 3054 fps | 99.7% |
| Rottweil R 905 | <<locked>> | 82% | 55,317 psi | 85% | 3064 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 52,576 psi | 81% | 3025 fps | 96.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 58,740 psi | 90% | 3123 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 57,435 psi | 88% | 3041 fps | 99.6% |
| Somchem S385 | <<locked>> | 82% | 55,608 psi | 86% | 3035 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 55,811 psi | 86% | 3022 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 55,230 psi | 85% | 3045 fps | 96.3% |
| Vihtavuori N555 | <<locked>> | 82% | 55,390 psi | 85% | 3035 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 58,639 psi | 90% | 3176 fps | 99.7% |
| Vihtavuori N565 | <<locked>> | 88% | 56,057 psi | 86% | 3107 fps | 99.6% |
| Vihtavuori N568 | <<locked>> | 92% | 58,218 psi | 90% | 3186 fps | 99.3% |
| Vihtavuori N570 | <<locked>> | 92% | 55,782 psi | 86% | 3182 fps | 97.5% |
| Winchester StaBALL HD | <<locked>> | 86% | 58,552 psi | 90% | 3150 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 55,376 psi | 85% | 3028 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% | 48,051 psi | 74% | 2881 fps | 100% |
| Accurate 8700 | <<locked>> | 98% | 46,862 psi | 72% | 2940 fps | 95% |
| Accurate High Country | <<locked>> | 80% | 53,127 psi | 82% | 3087 fps | 99.5% |
| Accurate MAGPRO | <<locked>> | 80% | 50,473 psi | 78% | 3028 fps | 98.3% |
| ADI AR 2209 | <<locked>> | 80% | 52,301 psi | 80% | 3022 fps | 99.8% |
| ADI AR 2213 | <<locked>> | 80% | 47,558 psi | 73% | 2963 fps | 98.6% |
| ADI AR 2217 | <<locked>> | 80% | 35,534 psi | 55% | 2684 fps | 95.4% |
| ADI AR 2218 | 84.1 gr | 92% | 47,050 psi | 72% | 3035 fps | 95.7% |
| ADI AR 2225 | <<locked>> | 80% | 32,851 psi | 51% | 2651 fps | 97.4% |
| Alliant Reloder-19 | <<locked>> | 80% | 51,924 psi | 80% | 3009 fps | 99.8% |
| Alliant Reloder-22 | <<locked>> | 80% | 48,312 psi | 74% | 2966 fps | 99.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 46,934 psi | 72% | 2890 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 41,278 psi | 64% | 2835 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 54,128 psi | 83% | 3081 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 48,907 psi | 75% | 3028 fps | 96.2% |
| Alliant Reloder-50 | <<locked>> | 94% | 48,921 psi | 75% | 3015 fps | 95.6% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 45,223 psi | 70% | 2867 fps | 95.6% |
| Bofors RP15 | <<locked>> | 80% | 44,962 psi | 69% | 2897 fps | 98.9% |
| Bofors RP30 | <<locked>> | 80% | 38,435 psi | 59% | 2762 fps | 96.5% |
| Bofors RP5 | <<locked>> | 80% | 48,312 psi | 74% | 2966 fps | 99.5% |
| Hodgdon H1000 | <<locked>> | 80% | 38,667 psi | 60% | 2766 fps | 97.3% |
| Hodgdon H4831 | <<locked>> | 80% | 49,821 psi | 77% | 2959 fps | 98.6% |
| Hodgdon H4831 SC | <<locked>> | 80% | 49,052 psi | 75% | 2946 fps | 98.4% |
| Hodgdon Retumbo | 69 gr | 80% | 40,277 psi | 62% | 2887 fps | 98.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,485 psi | 44% | 1801 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 50,430 psi | 78% | 2946 fps | 98.8% |
| IMR 7828 SSC | <<locked>> | 80% | 46,296 psi | 71% | 2946 fps | 98.4% |
| IMR 8133 Enduron | <<locked>> | 86% | 37,594 psi | 58% | 2756 fps | 96% |
| Lovex S071 | <<locked>> | 80% | 41,524 psi | 64% | 2749 fps | 99.7% |
| Norma 217 | <<locked>> | 80% | 30,821 psi | 47% | 2585 fps | 95.2% |
| Norma MRP | <<locked>> | 80% | 51,576 psi | 79% | 3041 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 46,978 psi | 72% | 2966 fps | 98.8% |
| Ramshot Magnum | <<locked>> | 80% | 42,337 psi | 65% | 2828 fps | 99.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,370 psi | 45% | 1847 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 39,987 psi | 62% | 2864 fps | 99.4% |
| ReloadSwiss RS 80 | <<locked>> | 82% | 39,668 psi | 61% | 2815 fps | 95.3% |
| Rottweil R 904 | <<locked>> | 80% | 52,663 psi | 81% | 2992 fps | 99.4% |
| Rottweil R 905 | <<locked>> | 80% | 51,750 psi | 80% | 3002 fps | 99.8% |
| SNPE Vectan SP 13 | <<locked>> | 98% | 48,965 psi | 75% | 2956 fps | 95.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 51,445 psi | 79% | 2999 fps | 99.8% |
| Somchem S361 | <<locked>> | 80% | 53,751 psi | 83% | 2979 fps | 99.2% |
| Somchem S385 | <<locked>> | 80% | 52,127 psi | 80% | 2976 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 45,687 psi | 70% | 2841 fps | 99.4% |
| Vihtavuori N170 | <<locked>> | 88% | 51,590 psi | 79% | 2976 fps | 95.4% |
| Vihtavuori N555 | <<locked>> | 80% | 51,866 psi | 80% | 2976 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 50,995 psi | 78% | 3041 fps | 98.8% |
| Vihtavuori N565 | <<locked>> | 80% | 42,757 psi | 66% | 2848 fps | 97.2% |
| Vihtavuori N568 | <<locked>> | 82% | 40,698 psi | 63% | 2831 fps | 95.1% |
| Vihtavuori N570 | 78.8 gr | 88% | 48,254 psi | 74% | 3035 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 46,804 psi | 72% | 2966 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 48,269 psi | 74% | 2904 fps | 99.5% |
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 51 powders for 6.5-300 Weatherby Mag. loaded with the .264 | 129gr | Hornady InterLock. Hodgdon Retumbo delivers the highest muzzle velocity at 3,228 fps; across all powders the maximum-charge window runs from 2,014 fps to 3,228 fps. Accurate 8700 gives the best case fill at 100 %, and 51 of the 51 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 129.0 gr projectile in 0.264" calls for a 1:10.5 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 | 129gr | Hornady InterLock 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.