Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .264 | 120gr | Sierra MatchKing 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% | 56,478 psi | 87% | 3114 fps | 100% |
| Accurate High Country | <<locked>> | 84% | 58,407 psi | 90% | 3274 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 84% | 55,419 psi | 85% | 3212 fps | 98.6% |
| ADI AR 2209 | <<locked>> | 84% | 57,232 psi | 88% | 3202 fps | 99.9% |
| ADI AR 2213 | <<locked>> | 86% | 56,101 psi | 86% | 3215 fps | 99.4% |
| ADI AR 2217 | <<locked>> | 94% | 55,216 psi | 85% | 3192 fps | 99.6% |
| ADI AR 2218 | <<locked>> | 98% | 55,941 psi | 86% | 3304 fps | 97.5% |
| ADI AR 2225 | <<locked>> | 98% | 58,581 psi | 90% | 3278 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 56,826 psi | 87% | 3186 fps | 99.9% |
| Alliant Reloder-22 | <<locked>> | 86% | 56,637 psi | 87% | 3209 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 88% | 58,407 psi | 90% | 3173 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 55,376 psi | 85% | 3192 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 55,376 psi | 85% | 3199 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 57,783 psi | 89% | 3281 fps | 97.6% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 57,899 psi | 89% | 3271 fps | 97.1% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 56,420 psi | 87% | 3169 fps | 97.7% |
| Bofors RP15 | <<locked>> | 88% | 56,057 psi | 86% | 3199 fps | 99.8% |
| Bofors RP30 | <<locked>> | 92% | 55,143 psi | 85% | 3199 fps | 99.6% |
| Bofors RP5 | <<locked>> | 86% | 56,637 psi | 87% | 3209 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 92% | 56,623 psi | 87% | 3215 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 84% | 54,882 psi | 84% | 3140 fps | 98.9% |
| Hodgdon H4831 SC | <<locked>> | 86% | 57,696 psi | 89% | 3189 fps | 99.2% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 57,551 psi | 89% | 3107 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 92% | 58,784 psi | 90% | 3346 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,768 psi | 58% | 2080 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 55,071 psi | 85% | 3120 fps | 99% |
| IMR 7828 SSC | <<locked>> | 88% | 58,436 psi | 90% | 3261 fps | 99.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 57,406 psi | 88% | 3251 fps | 99.7% |
| Lovex S071 | <<locked>> | 92% | 58,233 psi | 90% | 3140 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 58,740 psi | 90% | 3278 fps | 100% |
| Norma MRP | <<locked>> | 84% | 56,782 psi | 87% | 3225 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 55,738 psi | 86% | 3219 fps | 99.6% |
| Ramshot Magnum | <<locked>> | 90% | 58,581 psi | 90% | 3209 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,827 psi | 60% | 2129 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 55,492 psi | 85% | 3261 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 54,911 psi | 85% | 3219 fps | 98.7% |
| Rottweil R 904 | <<locked>> | 84% | 57,638 psi | 89% | 3169 fps | 99.6% |
| Rottweil R 905 | <<locked>> | 84% | 56,797 psi | 87% | 3182 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 56,420 psi | 87% | 3179 fps | 99.9% |
| Somchem S361 | <<locked>> | 82% | 55,332 psi | 85% | 3094 fps | 99% |
| Somchem S385 | <<locked>> | 84% | 57,014 psi | 88% | 3150 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 57,159 psi | 88% | 3136 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 56,521 psi | 87% | 3153 fps | 95.9% |
| Vihtavuori N555 | <<locked>> | 84% | 56,492 psi | 87% | 3150 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 56,101 psi | 86% | 3225 fps | 99.1% |
| Vihtavuori N565 | <<locked>> | 90% | 57,290 psi | 88% | 3219 fps | 99.4% |
| Vihtavuori N568 | <<locked>> | 92% | 55,245 psi | 85% | 3225 fps | 98.4% |
| Vihtavuori N570 | <<locked>> | 94% | 56,681 psi | 87% | 3287 fps | 97% |
| Winchester StaBALL HD | <<locked>> | 86% | 55,376 psi | 85% | 3209 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 57,029 psi | 88% | 3146 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% | 46,079 psi | 71% | 2933 fps | 99.9% |
| Accurate High Country | <<locked>> | 80% | 50,792 psi | 78% | 3133 fps | 98.7% |
| Accurate MAGPRO | <<locked>> | 80% | 48,022 psi | 74% | 3068 fps | 97.1% |
| ADI AR 2209 | <<locked>> | 80% | 50,111 psi | 77% | 3071 fps | 99.3% |
| ADI AR 2213 | <<locked>> | 80% | 45,310 psi | 70% | 3005 fps | 97.5% |
| ADI AR 2217 | <<locked>> | 84% | 38,798 psi | 60% | 2851 fps | 95.9% |
| ADI AR 2218 | 86.6 gr | 94% | 48,109 psi | 74% | 3136 fps | 95% |
| ADI AR 2225 | <<locked>> | 80% | 31,111 psi | 48% | 2671 fps | 95.5% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,980 psi | 77% | 3064 fps | 99.3% |
| Alliant Reloder-22 | <<locked>> | 80% | 46,093 psi | 71% | 3009 fps | 98.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,918 psi | 69% | 2946 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 39,073 psi | 60% | 2874 fps | 99.6% |
| Alliant Reloder-26 | <<locked>> | 80% | 51,503 psi | 79% | 3133 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 49,777 psi | 77% | 3130 fps | 95.6% |
| Alliant Reloder-50 | <<locked>> | 96% | 49,821 psi | 77% | 3117 fps | 95% |
| Baschieri & Pellagri 109 | <<locked>> | 82% | 46,441 psi | 71% | 2972 fps | 95.1% |
| Bofors RP15 | <<locked>> | 80% | 42,888 psi | 66% | 2940 fps | 97.9% |
| Bofors RP30 | <<locked>> | 82% | 39,146 psi | 60% | 2864 fps | 96% |
| Bofors RP5 | <<locked>> | 80% | 46,093 psi | 71% | 3009 fps | 98.7% |
| Hodgdon H1000 | <<locked>> | 80% | 36,753 psi | 57% | 2795 fps | 95.7% |
| Hodgdon H4831 | <<locked>> | 80% | 47,892 psi | 74% | 3009 fps | 97.6% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,949 psi | 72% | 2989 fps | 97.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,882 psi | 83% | 3051 fps | 100% |
| Hodgdon Retumbo | 69.5 gr | 80% | 38,087 psi | 59% | 2913 fps | 97.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,398 psi | 44% | 1864 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,515 psi | 75% | 2995 fps | 97.9% |
| IMR 7828 SSC | <<locked>> | 80% | 44,193 psi | 68% | 2989 fps | 97.3% |
| IMR 8133 Enduron | <<locked>> | 88% | 37,971 psi | 58% | 2848 fps | 95.3% |
| Lovex S071 | <<locked>> | 80% | 39,653 psi | 61% | 2792 fps | 99.1% |
| Norma 217 | <<locked>> | 84% | 33,431 psi | 51% | 2740 fps | 95.7% |
| Norma MRP | <<locked>> | 80% | 49,269 psi | 76% | 3091 fps | 99.8% |
| Ramshot Grand | <<locked>> | 80% | 44,614 psi | 69% | 3002 fps | 97.7% |
| Ramshot Magnum | <<locked>> | 80% | 40,205 psi | 62% | 2861 fps | 98.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,240 psi | 45% | 1913 fps | 100% |
| ReloadSwiss RS 76 | 74.4 gr | 80% | 37,637 psi | 58% | 2887 fps | 98.3% |
| ReloadSwiss RS 80 | <<locked>> | 86% | 43,700 psi | 67% | 2989 fps | 95.9% |
| Rottweil R 904 | <<locked>> | 80% | 50,647 psi | 78% | 3041 fps | 98.7% |
| Rottweil R 905 | <<locked>> | 80% | 49,545 psi | 76% | 3051 fps | 99.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 49,197 psi | 76% | 3045 fps | 99.2% |
| Somchem S361 | <<locked>> | 80% | 51,837 psi | 80% | 3031 fps | 98.4% |
| Somchem S385 | <<locked>> | 80% | 49,980 psi | 77% | 3025 fps | 99.7% |
| Vihtavuori N165 | <<locked>> | 80% | 43,859 psi | 68% | 2890 fps | 98.7% |
| Vihtavuori N170 | <<locked>> | 90% | 52,823 psi | 81% | 3084 fps | 95% |
| Vihtavuori N555 | <<locked>> | 80% | 49,545 psi | 76% | 3031 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 48,776 psi | 75% | 3084 fps | 97.9% |
| Vihtavuori N565 | <<locked>> | 80% | 40,785 psi | 63% | 2884 fps | 95.8% |
| Vihtavuori N568 | <<locked>> | 86% | 44,585 psi | 69% | 3005 fps | 95.7% |
| Vihtavuori N570 | <<locked>> | 92% | 52,750 psi | 81% | 3215 fps | 96% |
| Winchester StaBALL HD | <<locked>> | 80% | 43,918 psi | 68% | 3005 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 46,340 psi | 71% | 2953 fps | 98.8% |
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 | 120gr | Sierra MatchKing. Hodgdon Retumbo delivers the highest muzzle velocity at 3,346 fps; across all powders the maximum-charge window runs from 2,080 fps to 3,346 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 120.0 gr projectile in 0.264" calls for a 1:10.0 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. Hodgdon Retumbo, ReloadSwiss RS 76, ADI AR 2218 rank at the top here: for 6.5-300 Weatherby Mag. with the .264 | 120gr | Sierra MatchKing 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.