Load Specifications
Load data in caliber .300 Weath. Mag. with .308 | 185gr | Lapua Mega bullet and 75 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Winchester StaBALL HD, IMR 7828 SSC and Norma MRP.
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% | 57,638 psi | 90% | 2894 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 55,390 psi | 87% | 2877 fps | 100% |
| Accurate MAGPRO | <<locked>> | 94% | 56,217 psi | 88% | 2989 fps | 97.7% |
| ADI AR 2208 | <<locked>> | 82% | 56,579 psi | 89% | 2838 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 56,130 psi | 88% | 2930 fps | 99.3% |
| ADI AR 2213 | <<locked>> | 96% | 57,580 psi | 90% | 2992 fps | 98.7% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 48,269 psi | 76% | 2825 fps | 97.3% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 42,873 psi | 67% | 2779 fps | 98.9% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 56,318 psi | 88% | 2927 fps | 99.3% |
| Alliant Reloder-16 | <<locked>> | 88% | 56,362 psi | 88% | 2933 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 57,537 psi | 90% | 2949 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 55,622 psi | 87% | 2917 fps | 99.2% |
| Alliant Reloder-22 | <<locked>> | 96% | 57,493 psi | 90% | 2986 fps | 99.5% |
| Alliant Reloder-23 | <<locked>> | 96% | 54,911 psi | 86% | 2904 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 54,070 psi | 85% | 2959 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 92% | 55,332 psi | 87% | 2995 fps | 100% |
| Bofors RP15 | <<locked>> | 98% | 56,347 psi | 88% | 2966 fps | 99.3% |
| Bofors RP30ᴾ | <<locked>> | 100% | 50,227 psi | 79% | 2897 fps | 98.1% |
| Bofors RP5 | <<locked>> | 96% | 57,493 psi | 90% | 2986 fps | 99.5% |
| Bofors RP7 | <<locked>> | 84% | 54,288 psi | 85% | 2822 fps | 99.5% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 53,171 psi | 83% | 2913 fps | 98.8% |
| Hodgdon H414 | <<locked>> | 86% | 57,159 psi | 90% | 2930 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 84% | 56,144 psi | 88% | 2887 fps | 99.4% |
| Hodgdon H4831 | <<locked>> | 94% | 57,479 psi | 90% | 2927 fps | 98.2% |
| Hodgdon H4831 SC | <<locked>> | 94% | 56,347 psi | 88% | 2910 fps | 98% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 56,565 psi | 89% | 2854 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 52,997 psi | 83% | 3025 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 86% | 57,696 psi | 90% | 2969 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,985 psi | 58% | 1804 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 55,912 psi | 88% | 2864 fps | 99.7% |
| IMR 4451 Enduron | <<locked>> | 84% | 55,811 psi | 87% | 2848 fps | 99.8% |
| IMR 4831 | <<locked>> | 88% | 55,753 psi | 87% | 2867 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 55,027 psi | 86% | 2858 fps | 97.9% |
| IMR 7828 SSC | <<locked>> | 96% | 55,376 psi | 87% | 2966 fps | 98.5% |
| Lovex S065 | <<locked>> | 86% | 56,304 psi | 88% | 2844 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 54,520 psi | 85% | 2841 fps | 99.8% |
| Lovex S071ᴾ | <<locked>> | 100% | 54,911 psi | 86% | 2858 fps | 100% |
| Norma 204 | <<locked>> | 88% | 56,927 psi | 89% | 2917 fps | 99.2% |
| Norma 217ᴾ | <<locked>> | 100% | 38,464 psi | 60% | 2700 fps | 97% |
| Norma MRP | <<locked>> | 94% | 57,435 psi | 90% | 3009 fps | 99.9% |
| Norma URP | <<locked>> | 88% | 57,522 psi | 90% | 2913 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 56,014 psi | 88% | 2989 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 88% | 56,362 psi | 88% | 2920 fps | 100% |
| Ramshot Magnum | <<locked>> | 98% | 54,418 psi | 85% | 2923 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,898 psi | 59% | 1847 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 56,985 psi | 89% | 2933 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 55,288 psi | 87% | 2897 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 57,653 psi | 90% | 2986 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 53,635 psi | 84% | 3022 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 48,675 psi | 76% | 2904 fps | 96.2% |
| Rottweil R 903 | <<locked>> | 82% | 55,593 psi | 87% | 2825 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 57,334 psi | 90% | 2900 fps | 98.7% |
| Rottweil R 905 | <<locked>> | 92% | 55,100 psi | 86% | 2907 fps | 99.3% |
| Rottweil R 907 | <<locked>> | 84% | 54,288 psi | 85% | 2822 fps | 99.5% |
| Shooters World Long Rifle | <<locked>> | 86% | 56,304 psi | 88% | 2844 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 54,520 psi | 85% | 2841 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 57,116 psi | 90% | 2884 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 55,434 psi | 87% | 2700 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 55,753 psi | 87% | 2802 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 54,665 psi | 86% | 2900 fps | 99.2% |
| Somchem S355 | <<locked>> | 82% | 55,390 psi | 87% | 2818 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 55,259 psi | 87% | 2838 fps | 97.8% |
| Somchem S365 | <<locked>> | 88% | 54,201 psi | 85% | 2864 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 55,564 psi | 87% | 2881 fps | 99.7% |
| Vihtavuori N150 | <<locked>> | 84% | 56,565 psi | 89% | 2792 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 55,666 psi | 87% | 2854 fps | 100% |
| Vihtavuori N165 | <<locked>> | 96% | 55,085 psi | 86% | 2861 fps | 99.5% |
| Vihtavuori N550 | <<locked>> | 86% | 54,897 psi | 86% | 2858 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 57,174 psi | 90% | 2930 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 57,276 psi | 90% | 3005 fps | 98.4% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 57,029 psi | 89% | 2982 fps | 98.5% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 55,172 psi | 86% | 2815 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 57,377 psi | 90% | 2933 fps | 99.9% |
| Winchester StaBALL HD | <<locked>> | 98% | 56,405 psi | 88% | 3041 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 55,637 psi | 87% | 2877 fps | 99.2% |
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% | 33,692 psi | 53% | 2451 fps | 96.6% |
| Accurate 4350 | <<locked>> | 80% | 45,194 psi | 71% | 2710 fps | 99.9% |
| Accurate MAGPRO | <<locked>> | 88% | 45,542 psi | 71% | 2795 fps | 95.1% |
| ADI AR 2208 | <<locked>> | 80% | 53,055 psi | 83% | 2782 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 37,666 psi | 59% | 2575 fps | 95.1% |
| ADI AR 2213 | <<locked>> | 88% | 44,005 psi | 69% | 2746 fps | 95.8% |
| ADI AR 2217 | <<locked>> | 96% | 42,250 psi | 66% | 2700 fps | 95.5% |
| ADI AR 2225 | <<locked>> | 92% | 33,156 psi | 52% | 2536 fps | 95.1% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 38,058 psi | 60% | 2579 fps | 95.3% |
| Alliant Reloder-16 | <<locked>> | 80% | 43,192 psi | 68% | 2713 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 80% | 50,009 psi | 78% | 2838 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 37,724 psi | 59% | 2572 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 84% | 38,435 psi | 60% | 2631 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 32,227 psi | 51% | 2477 fps | 99.2% |
| Alliant Reloder-25 | <<locked>> | 82% | 30,095 psi | 47% | 2438 fps | 95.6% |
| Alliant Reloder-26 | <<locked>> | 80% | 35,201 psi | 55% | 2612 fps | 98.5% |
| Bofors RP15 | <<locked>> | 86% | 38,101 psi | 60% | 2621 fps | 95.3% |
| Bofors RP30 | <<locked>> | 94% | 40,930 psi | 64% | 2717 fps | 95.6% |
| Bofors RP5 | <<locked>> | 84% | 38,435 psi | 60% | 2631 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 48,051 psi | 75% | 2717 fps | 98.8% |
| Hodgdon H1000 | <<locked>> | 92% | 40,538 psi | 64% | 2667 fps | 95.6% |
| Hodgdon H414 | <<locked>> | 80% | 46,760 psi | 73% | 2756 fps | 99% |
| Hodgdon H4350 | <<locked>> | 80% | 49,342 psi | 77% | 2772 fps | 98.5% |
| Hodgdon H4831 | <<locked>> | 86% | 43,874 psi | 69% | 2687 fps | 95.1% |
| Hodgdon H4831 SC | <<locked>> | 88% | 46,180 psi | 72% | 2733 fps | 95.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 40,828 psi | 64% | 2602 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 38,058 psi | 60% | 2700 fps | 96.1% |
| Hodgdon Superformance | <<locked>> | 80% | 46,151 psi | 72% | 2779 fps | 98.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,731 psi | 43% | 1611 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 43,366 psi | 68% | 2644 fps | 98% |
| IMR 4451 Enduron | <<locked>> | 80% | 49,327 psi | 77% | 2740 fps | 99.2% |
| IMR 4831 | <<locked>> | 80% | 43,091 psi | 68% | 2657 fps | 99.8% |
| IMR 4955 Enduron | <<locked>> | 84% | 42,728 psi | 67% | 2631 fps | 95% |
| IMR 7828 SSC | 73.8 gr | 88% | 42,293 psi | 66% | 2720 fps | 95.3% |
| Lovex S065 | <<locked>> | 80% | 46,833 psi | 73% | 2687 fps | 99.6% |
| Lovex S070 | <<locked>> | 80% | 45,252 psi | 71% | 2680 fps | 98.9% |
| Lovex S071 | <<locked>> | 82% | 30,908 psi | 48% | 2382 fps | 95.5% |
| Norma 204 | <<locked>> | 80% | 43,424 psi | 68% | 2680 fps | 96.8% |
| Norma 217 | <<locked>> | 98% | 36,100 psi | 57% | 2644 fps | 96% |
| Norma MRP | 69.7 gr | 80% | 35,041 psi | 55% | 2575 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 44,396 psi | 70% | 2697 fps | 99.8% |
| Ramshot Grand | <<locked>> | 88% | 41,974 psi | 66% | 2726 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 43,221 psi | 68% | 2690 fps | 99% |
| Ramshot Magnum | <<locked>> | 86% | 34,940 psi | 55% | 2543 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,297 psi | 44% | 1650 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 53,127 psi | 83% | 2881 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 45,078 psi | 71% | 2730 fps | 99.8% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 43,178 psi | 68% | 2743 fps | 99.7% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 34,969 psi | 55% | 2615 fps | 95.9% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 45,136 psi | 71% | 2831 fps | 95.1% |
| Rottweil R 903 | <<locked>> | 80% | 52,243 psi | 82% | 2776 fps | 100% |
| Rottweil R 904 | <<locked>> | 82% | 41,713 psi | 65% | 2618 fps | 95.3% |
| Rottweil R 905 | <<locked>> | 80% | 37,043 psi | 58% | 2559 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 80% | 48,051 psi | 75% | 2717 fps | 98.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 46,833 psi | 73% | 2687 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 80% | 45,252 psi | 71% | 2680 fps | 98.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 53,534 psi | 84% | 2831 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 52,286 psi | 82% | 2657 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 45,774 psi | 72% | 2635 fps | 98.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 36,709 psi | 58% | 2552 fps | 95% |
| Somchem S355 | <<locked>> | 80% | 51,895 psi | 81% | 2769 fps | 100% |
| Somchem S361 | <<locked>> | 84% | 45,368 psi | 71% | 2664 fps | 95.5% |
| Somchem S365 | <<locked>> | 80% | 41,220 psi | 65% | 2654 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 37,550 psi | 59% | 2543 fps | 96.3% |
| Vihtavuori N150 | <<locked>> | 80% | 49,792 psi | 78% | 2694 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 45,759 psi | 72% | 2690 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 84% | 37,130 psi | 58% | 2526 fps | 95.7% |
| Vihtavuori N550 | <<locked>> | 80% | 45,049 psi | 71% | 2694 fps | 99.8% |
| Vihtavuori N555 | <<locked>> | 80% | 36,274 psi | 57% | 2559 fps | 99.2% |
| Vihtavuori N560 | <<locked>> | 86% | 43,410 psi | 68% | 2749 fps | 95.1% |
| Vihtavuori N565 | <<locked>> | 92% | 43,410 psi | 68% | 2740 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 44,831 psi | 70% | 2657 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 46,905 psi | 74% | 2759 fps | 99% |
| Winchester StaBALL HD | 69 gr | 80% | 28,703 psi | 45% | 2487 fps | 99.3% |
| Winchester Supreme 780 | <<locked>> | 84% | 39,291 psi | 62% | 2582 fps | 95.8% |
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 75 powders for .300 Weath. Mag. loaded with the .308 | 185gr | Lapua Mega. Winchester StaBALL HD delivers the highest muzzle velocity at 3,041 fps; across all powders the maximum-charge window runs from 1,804 fps to 3,041 fps. ADI AR 2217 gives the best case fill at 100 %, and 75 of the 75 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 185.0 gr projectile in 0.308" calls for a 1:15.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Alliant Reloder-25 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. Winchester StaBALL HD, IMR 7828 SSC, Norma MRP rank at the top here: for .300 Weath. Mag. with the .308 | 185gr | Lapua Mega 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.