Load Specifications
Load data in caliber 6.5-300 Weatherby Mag. with .263 | 139gr | Prvi Partizan FMJ BT bullet and 49 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 Alliant Reloder-33.
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% | 57,522 psi | 89% | 2940 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 53,606 psi | 83% | 2982 fps | 97.7% |
| Accurate MAGPRO | <<locked>> | 82% | 56,782 psi | 87% | 3051 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 82% | 58,218 psi | 90% | 3025 fps | 100% |
| ADI AR 2213 | <<locked>> | 84% | 57,334 psi | 88% | 3048 fps | 100% |
| ADI AR 2217 | <<locked>> | 92% | 57,087 psi | 88% | 3035 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 57,885 psi | 89% | 3169 fps | 99.1% |
| ADI AR 2225 | <<locked>> | 94% | 57,014 psi | 88% | 3058 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 57,827 psi | 89% | 3015 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 57,885 psi | 89% | 3041 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 84% | 56,347 psi | 87% | 2943 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 88% | 57,188 psi | 88% | 3022 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 55,854 psi | 86% | 3071 fps | 98.5% |
| Alliant Reloder-50 | <<locked>> | 96% | 56,101 psi | 86% | 3064 fps | 98.1% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 57,232 psi | 88% | 3005 fps | 98.9% |
| Bofors RP15 | <<locked>> | 86% | 57,319 psi | 88% | 3031 fps | 100% |
| Bofors RP30 | <<locked>> | 90% | 57,014 psi | 88% | 3045 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 57,885 psi | 89% | 3041 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 58,523 psi | 90% | 3054 fps | 100% |
| Hodgdon H4831 | <<locked>> | 82% | 55,695 psi | 86% | 2972 fps | 99.7% |
| Hodgdon H4831 SC | <<locked>> | 84% | 58,566 psi | 90% | 3022 fps | 99.9% |
| Hodgdon Retumbo | <<locked>> | 88% | 57,043 psi | 88% | 3117 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,130 psi | 59% | 1946 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 55,695 psi | 86% | 2949 fps | 99.8% |
| IMR 7828 SSC | <<locked>> | 84% | 55,956 psi | 86% | 3031 fps | 99.9% |
| IMR 7977 Enduron | <<locked>> | 90% | 58,146 psi | 89% | 2966 fps | 96.3% |
| IMR 8133 Enduron | <<locked>> | 96% | 55,724 psi | 86% | 3038 fps | 100% |
| Lovex S071 | <<locked>> | 88% | 55,985 psi | 86% | 2917 fps | 100% |
| Norma 217 | <<locked>> | 96% | 57,493 psi | 88% | 3064 fps | 100% |
| Norma MRP | <<locked>> | 82% | 58,059 psi | 89% | 3051 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 57,566 psi | 89% | 3058 fps | 100% |
| Ramshot Magnum | <<locked>> | 86% | 56,028 psi | 86% | 2982 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,102 psi | 60% | 1988 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 57,856 psi | 89% | 3100 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 56,884 psi | 88% | 3071 fps | 99.7% |
| Rottweil R 904 | <<locked>> | 82% | 58,320 psi | 90% | 2992 fps | 100% |
| Rottweil R 905 | <<locked>> | 82% | 57,841 psi | 89% | 3009 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 55,419 psi | 85% | 2989 fps | 97.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 57,479 psi | 88% | 3005 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 58,059 psi | 89% | 2976 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 58,160 psi | 90% | 2966 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 57,595 psi | 89% | 2999 fps | 97.6% |
| Vihtavuori N555 | <<locked>> | 82% | 57,769 psi | 89% | 2969 fps | 100% |
| Vihtavuori N560 | <<locked>> | 82% | 57,276 psi | 88% | 3058 fps | 99.8% |
| Vihtavuori N565 | <<locked>> | 86% | 55,158 psi | 85% | 2999 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 90% | 57,276 psi | 88% | 3077 fps | 99.5% |
| Vihtavuori N570 | <<locked>> | 90% | 54,737 psi | 84% | 3074 fps | 98% |
| Winchester StaBALL HD | <<locked>> | 84% | 57,624 psi | 89% | 3035 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 57,754 psi | 89% | 2972 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% | 50,372 psi | 78% | 2828 fps | 100% |
| Accurate 8700 | <<locked>> | 96% | 46,340 psi | 71% | 2848 fps | 95.8% |
| Accurate MAGPRO | <<locked>> | 80% | 52,968 psi | 82% | 2986 fps | 99.2% |
| ADI AR 2209 | <<locked>> | 80% | 54,447 psi | 84% | 2963 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 49,777 psi | 77% | 2917 fps | 99.4% |
| ADI AR 2217 | <<locked>> | 80% | 37,478 psi | 58% | 2654 fps | 97.1% |
| ADI AR 2218 | 79.8 gr | 88% | 42,902 psi | 66% | 2861 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 80% | 34,795 psi | 54% | 2625 fps | 98.9% |
| Alliant Reloder-19 | <<locked>> | 80% | 54,186 psi | 83% | 2953 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 50,517 psi | 78% | 2917 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 49,298 psi | 76% | 2835 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 43,468 psi | 67% | 2792 fps | 100% |
| Alliant Reloder-33 | 79.4 gr | 86% | 44,570 psi | 69% | 2851 fps | 95.7% |
| Alliant Reloder-50 | <<locked>> | 90% | 45,005 psi | 69% | 2851 fps | 95.2% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 47,079 psi | 72% | 2822 fps | 96.9% |
| Bofors RP15 | <<locked>> | 80% | 47,224 psi | 73% | 2851 fps | 99.6% |
| Bofors RP30 | <<locked>> | 80% | 40,640 psi | 63% | 2733 fps | 98% |
| Bofors RP5 | <<locked>> | 80% | 50,517 psi | 78% | 2917 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 80% | 40,843 psi | 63% | 2733 fps | 98.6% |
| Hodgdon H4831 | <<locked>> | 80% | 52,112 psi | 80% | 2910 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 80% | 51,111 psi | 79% | 2894 fps | 99.2% |
| Hodgdon Retumbo | <<locked>> | 80% | 42,786 psi | 66% | 2858 fps | 99.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,587 psi | 44% | 1739 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 52,272 psi | 80% | 2890 fps | 99.5% |
| IMR 7828 SSC | <<locked>> | 80% | 48,762 psi | 75% | 2904 fps | 99.3% |
| IMR 7977 Enduron | <<locked>> | 88% | 54,491 psi | 84% | 2904 fps | 95.4% |
| IMR 8133 Enduron | <<locked>> | 82% | 34,722 psi | 53% | 2602 fps | 95.7% |
| Lovex S071 | <<locked>> | 80% | 43,526 psi | 67% | 2703 fps | 100% |
| Norma 217 | <<locked>> | 80% | 32,953 psi | 51% | 2566 fps | 97.2% |
| Norma MRP | <<locked>> | 80% | 54,317 psi | 84% | 2992 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 49,748 psi | 77% | 2927 fps | 99.6% |
| Ramshot Magnum | <<locked>> | 80% | 44,846 psi | 69% | 2792 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,501 psi | 45% | 1781 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 42,540 psi | 65% | 2831 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 39,131 psi | 60% | 2717 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 54,636 psi | 84% | 2933 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 80% | 54,157 psi | 83% | 2949 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 96% | 48,269 psi | 74% | 2861 fps | 95.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 53,809 psi | 83% | 2946 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 54,244 psi | 83% | 2917 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 47,834 psi | 74% | 2795 fps | 99.9% |
| Vihtavuori N170 | <<locked>> | 84% | 47,123 psi | 73% | 2808 fps | 95% |
| Vihtavuori N555 | <<locked>> | 80% | 54,346 psi | 84% | 2920 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 53,621 psi | 83% | 2995 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 80% | 45,078 psi | 69% | 2808 fps | 98.5% |
| Vihtavuori N568 | <<locked>> | 80% | 40,001 psi | 62% | 2733 fps | 95.7% |
| Vihtavuori N570 | 74.6 gr | 84% | 44,179 psi | 68% | 2858 fps | 95% |
| Winchester StaBALL HD | <<locked>> | 80% | 49,719 psi | 77% | 2917 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 50,531 psi | 78% | 2854 fps | 99.9% |
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 49 powders for 6.5-300 Weatherby Mag. loaded with the .263 | 139gr | Prvi Partizan FMJ BT. ADI AR 2218 delivers the highest muzzle velocity at 3,169 fps; across all powders the maximum-charge window runs from 1,946 fps to 3,169 fps. Accurate 8700 gives the best case fill at 100 %, and 49 of the 49 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 59–90 %, leaving at least 10 % headroom. The 139.0 gr projectile in 0.263" calls for a 1:10.0 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, Alliant Reloder-33 rank at the top here: for 6.5-300 Weatherby Mag. with the .263 | 139gr | Prvi Partizan FMJ BT 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.