Load Specifications
Load data in caliber .300 Weath. Mag. with .308 | 170gr | Swift A-Frame bullet and 77 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Norma MRP, Vihtavuori N560 and ADI AR 2213.
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>> | 96% | 55,100 psi | 86% | 2969 fps | 99.9% |
| Accurate 4350 | <<locked>> | 88% | 56,681 psi | 89% | 3015 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 57,551 psi | 90% | 3120 fps | 97.2% |
| ADI AR 2208 | <<locked>> | 82% | 54,534 psi | 85% | 2923 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 57,508 psi | 90% | 3068 fps | 98.9% |
| ADI AR 2213 | <<locked>> | 96% | 55,129 psi | 86% | 3061 fps | 97.7% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 40,944 psi | 64% | 2831 fps | 97.5% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 57,624 psi | 90% | 3061 fps | 99% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 55,680 psi | 87% | 2949 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 57,421 psi | 90% | 3071 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 54,940 psi | 86% | 3031 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 56,869 psi | 89% | 3051 fps | 98.9% |
| Alliant Reloder-22 | <<locked>> | 96% | 54,839 psi | 86% | 3054 fps | 98.7% |
| Alliant Reloder-23 | <<locked>> | 98% | 55,840 psi | 88% | 3038 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 51,648 psi | 81% | 3035 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 94% | 56,304 psi | 88% | 3127 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 57,493 psi | 90% | 3097 fps | 99% |
| Bofors RP3 | <<locked>> | 82% | 56,739 psi | 89% | 2966 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 47,456 psi | 74% | 2953 fps | 96.7% |
| Bofors RP5 | <<locked>> | 96% | 54,839 psi | 86% | 3054 fps | 98.7% |
| Bofors RP7 | <<locked>> | 86% | 55,738 psi | 87% | 2956 fps | 99.3% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 50,879 psi | 80% | 2976 fps | 97.7% |
| Hodgdon H380 | <<locked>> | 82% | 56,884 psi | 89% | 2986 fps | 100% |
| Hodgdon H414 | <<locked>> | 86% | 54,781 psi | 86% | 3009 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 86% | 57,653 psi | 90% | 3025 fps | 99.1% |
| Hodgdon H4831 | <<locked>> | 94% | 55,172 psi | 86% | 2999 fps | 97% |
| Hodgdon H4831 SC | <<locked>> | 94% | 54,099 psi | 85% | 2982 fps | 96.8% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 57,624 psi | 90% | 2989 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 50,546 psi | 79% | 3084 fps | 98.9% |
| Hodgdon Superformance | <<locked>> | 86% | 55,201 psi | 87% | 3045 fps | 99.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,941 psi | 58% | 1886 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 57,421 psi | 90% | 2959 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 57,276 psi | 90% | 2995 fps | 99.5% |
| IMR 4451 Enduron | <<locked>> | 86% | 57,290 psi | 90% | 2986 fps | 99.6% |
| IMR 4831 | <<locked>> | 90% | 56,971 psi | 89% | 3002 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 56,449 psi | 88% | 2986 fps | 97.4% |
| IMR 7828 SSC | <<locked>> | 98% | 56,623 psi | 89% | 3097 fps | 98% |
| Lovex S065 | <<locked>> | 86% | 54,389 psi | 85% | 2930 fps | 99.9% |
| Lovex S070 | <<locked>> | 88% | 55,912 psi | 88% | 2976 fps | 99.7% |
| Lovex S071ᴾ | <<locked>> | 100% | 52,504 psi | 82% | 2930 fps | 99.7% |
| Norma 204 | <<locked>> | 88% | 54,447 psi | 85% | 2989 fps | 98.4% |
| Norma MRP | <<locked>> | 94% | 54,607 psi | 86% | 3081 fps | 99.5% |
| Norma URP | <<locked>> | 88% | 55,158 psi | 86% | 2995 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 57,319 psi | 90% | 3120 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 57,609 psi | 90% | 3054 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 55,666 psi | 87% | 3054 fps | 99.4% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,623 psi | 59% | 1929 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 56,608 psi | 89% | 2969 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 54,302 psi | 85% | 3018 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 56,666 psi | 89% | 3035 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 54,911 psi | 86% | 3061 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 50,966 psi | 80% | 3084 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 84% | 57,043 psi | 89% | 2966 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 55,216 psi | 87% | 2972 fps | 97.7% |
| Rottweil R 905 | <<locked>> | 94% | 56,304 psi | 88% | 3038 fps | 98.9% |
| Rottweil R 907 | <<locked>> | 86% | 55,738 psi | 87% | 2956 fps | 99.3% |
| Shooters World Long Rifle | <<locked>> | 86% | 54,389 psi | 85% | 2930 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 88% | 55,912 psi | 88% | 2976 fps | 99.7% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 54,766 psi | 86% | 2969 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 57,116 psi | 90% | 2838 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 57,145 psi | 90% | 2933 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 55,854 psi | 88% | 3031 fps | 98.8% |
| Somchem S355 | <<locked>> | 84% | 56,666 psi | 89% | 2956 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 56,811 psi | 89% | 2966 fps | 97.3% |
| Somchem S365 | <<locked>> | 90% | 55,245 psi | 87% | 2999 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 56,942 psi | 89% | 3012 fps | 99.4% |
| Vihtavuori N150 | <<locked>> | 84% | 54,447 psi | 85% | 2881 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 57,029 psi | 89% | 2989 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 56,333 psi | 88% | 2989 fps | 99.2% |
| Vihtavuori N550 | <<locked>> | 88% | 56,115 psi | 88% | 2992 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 54,534 psi | 85% | 3012 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 54,592 psi | 86% | 3071 fps | 97.2% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 54,056 psi | 85% | 3041 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 56,637 psi | 89% | 2949 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 54,984 psi | 86% | 3012 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 56,971 psi | 89% | 3173 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 57,029 psi | 89% | 3009 fps | 98.9% |
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>> | 82% | 34,301 psi | 54% | 2562 fps | 95.9% |
| Accurate 4350 | <<locked>> | 80% | 43,178 psi | 68% | 2779 fps | 99.5% |
| Accurate MAGPRO | <<locked>> | 92% | 49,792 psi | 78% | 2982 fps | 95.4% |
| ADI AR 2208 | <<locked>> | 80% | 51,358 psi | 80% | 2871 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 41,220 psi | 65% | 2756 fps | 95.3% |
| ADI AR 2213 | 77.6 gr | 90% | 44,962 psi | 70% | 2867 fps | 95% |
| ADI AR 2225 | <<locked>> | 96% | 36,042 psi | 56% | 2703 fps | 95.4% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 41,597 psi | 65% | 2759 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 52,243 psi | 82% | 2894 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 41,379 psi | 65% | 2785 fps | 99.5% |
| Alliant Reloder-17 | <<locked>> | 80% | 47,601 psi | 75% | 2913 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 41,191 psi | 65% | 2753 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 88% | 41,872 psi | 66% | 2808 fps | 95.8% |
| Alliant Reloder-23 | <<locked>> | 80% | 30,719 psi | 48% | 2533 fps | 98.1% |
| Alliant Reloder-25 | <<locked>> | 86% | 32,677 psi | 51% | 2608 fps | 95.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 33,286 psi | 52% | 2657 fps | 97% |
| Bofors RP15 | <<locked>> | 90% | 41,481 psi | 65% | 2799 fps | 95.5% |
| Bofors RP3 | <<locked>> | 80% | 53,142 psi | 83% | 2910 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 44,324 psi | 69% | 2887 fps | 95.7% |
| Bofors RP5 | <<locked>> | 88% | 41,872 psi | 66% | 2808 fps | 95.8% |
| Bofors RP7 | <<locked>> | 80% | 46,209 psi | 72% | 2785 fps | 97.8% |
| Hodgdon H1000 | <<locked>> | 96% | 44,280 psi | 69% | 2844 fps | 95.8% |
| Hodgdon H380 | <<locked>> | 80% | 53,171 psi | 83% | 2927 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 44,744 psi | 70% | 2825 fps | 98% |
| Hodgdon H4350 | <<locked>> | 80% | 47,471 psi | 74% | 2844 fps | 97.5% |
| Hodgdon H4831 | <<locked>> | 90% | 48,109 psi | 75% | 2874 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 90% | 47,152 psi | 74% | 2858 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 38,914 psi | 61% | 2667 fps | 99.8% |
| Hodgdon Retumbo | <<locked>> | 92% | 38,725 psi | 61% | 2812 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 44,121 psi | 69% | 2844 fps | 97.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,586 psi | 43% | 1683 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 54,056 psi | 85% | 2907 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 41,742 psi | 65% | 2710 fps | 96.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 47,485 psi | 74% | 2812 fps | 98.5% |
| IMR 4831 | <<locked>> | 80% | 41,104 psi | 64% | 2723 fps | 99.2% |
| IMR 4955 Enduron | <<locked>> | 88% | 46,760 psi | 73% | 2815 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 92% | 46,093 psi | 72% | 2904 fps | 95.5% |
| Lovex S065 | <<locked>> | 80% | 45,179 psi | 71% | 2766 fps | 99% |
| Lovex S070 | <<locked>> | 80% | 43,424 psi | 68% | 2746 fps | 97.9% |
| Lovex S071 | <<locked>> | 86% | 33,475 psi | 52% | 2543 fps | 95.6% |
| Norma 204 | <<locked>> | 80% | 41,539 psi | 65% | 2743 fps | 95.3% |
| Norma MRP | 73 gr | 82% | 35,694 psi | 56% | 2690 fps | 95% |
| Norma URP | <<locked>> | 80% | 42,380 psi | 66% | 2766 fps | 99.3% |
| Ramshot Grand | <<locked>> | 92% | 46,064 psi | 72% | 2913 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 41,278 psi | 65% | 2756 fps | 98% |
| Ramshot Magnum | <<locked>> | 90% | 38,232 psi | 60% | 2717 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,108 psi | 44% | 1722 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 52,982 psi | 83% | 2910 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 50,488 psi | 79% | 2963 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 42,888 psi | 67% | 2795 fps | 99.3% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 41,263 psi | 65% | 2805 fps | 99% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 38,261 psi | 60% | 2795 fps | 96.3% |
| Rottweil R 903 | <<locked>> | 80% | 50,024 psi | 78% | 2858 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 45,440 psi | 71% | 2795 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 84% | 40,335 psi | 63% | 2736 fps | 95.4% |
| Rottweil R 907 | <<locked>> | 80% | 46,209 psi | 72% | 2785 fps | 97.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 45,179 psi | 71% | 2766 fps | 99% |
| Shooters World SW4350 | <<locked>> | 80% | 43,424 psi | 68% | 2746 fps | 97.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 51,387 psi | 81% | 2913 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 50,560 psi | 79% | 2746 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 44,179 psi | 69% | 2707 fps | 98% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 39,987 psi | 63% | 2730 fps | 95.2% |
| Somchem S355 | <<locked>> | 80% | 50,053 psi | 78% | 2854 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 49,821 psi | 78% | 2848 fps | 95.8% |
| Somchem S365 | <<locked>> | 80% | 39,218 psi | 61% | 2723 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 38,334 psi | 60% | 2657 fps | 95.6% |
| Vihtavuori N150 | <<locked>> | 80% | 47,834 psi | 75% | 2776 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 43,888 psi | 69% | 2766 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 86% | 37,942 psi | 59% | 2644 fps | 95.1% |
| Vihtavuori N550 | <<locked>> | 80% | 43,163 psi | 68% | 2762 fps | 99.3% |
| Vihtavuori N555 | <<locked>> | 80% | 34,330 psi | 54% | 2612 fps | 98.1% |
| Vihtavuori N560 | 80.1 gr | 90% | 47,427 psi | 74% | 2940 fps | 95.4% |
| Vihtavuori N565 | <<locked>> | 96% | 47,152 psi | 74% | 2917 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 42,960 psi | 67% | 2730 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 44,933 psi | 70% | 2828 fps | 98.1% |
| Winchester StaBALL HD | <<locked>> | 80% | 27,267 psi | 43% | 2520 fps | 97.6% |
| Winchester Supreme 780 | <<locked>> | 86% | 40,335 psi | 63% | 2703 fps | 95.1% |
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 77 powders for .300 Weath. Mag. loaded with the .308 | 170gr | Swift A-Frame. Winchester StaBALL HD delivers the highest muzzle velocity at 3,173 fps; across all powders the maximum-charge window runs from 1,886 fps to 3,173 fps. ADI AR 2225 gives the best case fill at 100 %, and 77 of the 77 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 170.0 gr projectile in 0.308" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. ADI AR 2225, Alliant Reloder-25, Bofors RP15 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. Norma MRP, Vihtavuori N560, ADI AR 2213 rank at the top here: for .300 Weath. Mag. with the .308 | 170gr | Swift A-Frame 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.