Load Specifications
Load data in caliber .300 Win. Mag. with .308 | 205gr | Sierra GameKing bullet and 82 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 Accurate MAGPRO.
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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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 84% | 55,709 psi | 89% | 2621 fps | 99.7% |
| Accurate 3100 | <<locked>> | 96% | 53,940 psi | 86% | 2671 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 55,753 psi | 89% | 2707 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 53,011 psi | 85% | 2759 fps | 96.7% |
| ADI AR 2208 | <<locked>> | 82% | 54,041 psi | 87% | 2621 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 52,765 psi | 85% | 2703 fps | 99% |
| ADI AR 2213 | <<locked>> | 96% | 53,911 psi | 86% | 2756 fps | 98.4% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 45,092 psi | 72% | 2598 fps | 96.7% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 40,016 psi | 64% | 2562 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 55,216 psi | 89% | 2644 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 56,391 psi | 90% | 2756 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 53,998 psi | 87% | 2723 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 55,767 psi | 89% | 2746 fps | 99.4% |
| Alliant Reloder-22 | <<locked>> | 96% | 53,548 psi | 86% | 2753 fps | 99.3% |
| Alliant Reloder-23 | <<locked>> | 98% | 54,578 psi | 88% | 2730 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 50,343 psi | 81% | 2733 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 94% | 54,621 psi | 88% | 2815 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 98% | 56,260 psi | 90% | 2723 fps | 96% |
| Bofors RP15ᴾ | <<locked>> | 100% | 56,159 psi | 90% | 2792 fps | 99.5% |
| Bofors RP3 | <<locked>> | 82% | 56,115 psi | 90% | 2661 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 46,296 psi | 74% | 2671 fps | 97.6% |
| Bofors RP5 | <<locked>> | 96% | 53,548 psi | 86% | 2753 fps | 99.3% |
| Bofors RP7 | <<locked>> | 86% | 55,172 psi | 88% | 2657 fps | 99.7% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 46,354 psi | 74% | 2625 fps | 97.7% |
| Hodgdon H380 | <<locked>> | 82% | 56,101 psi | 90% | 2677 fps | 100% |
| Hodgdon H414 | <<locked>> | 84% | 54,969 psi | 88% | 2723 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 88% | 55,376 psi | 89% | 2694 fps | 99.5% |
| Hodgdon H4831 | <<locked>> | 98% | 53,345 psi | 86% | 2690 fps | 97.7% |
| Hodgdon H4831 SC | <<locked>> | 94% | 53,084 psi | 85% | 2687 fps | 97.6% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 53,258 psi | 85% | 2635 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 49,327 psi | 79% | 2785 fps | 99.4% |
| Hodgdon Superformance | <<locked>> | 86% | 53,911 psi | 86% | 2740 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,854 psi | 59% | 1657 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,420 psi | 90% | 2644 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 54,998 psi | 88% | 2631 fps | 99.9% |
| IMR 4350 | <<locked>> | 88% | 52,924 psi | 85% | 2641 fps | 99.6% |
| IMR 4451 Enduron | <<locked>> | 84% | 53,374 psi | 86% | 2631 fps | 99.7% |
| IMR 4831 | <<locked>> | 92% | 53,824 psi | 86% | 2667 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 55,564 psi | 89% | 2690 fps | 98.2% |
| IMR 7828 SSC | <<locked>> | 96% | 55,753 psi | 89% | 2799 fps | 98.8% |
| Lovex S065 | <<locked>> | 86% | 53,751 psi | 86% | 2628 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 55,143 psi | 88% | 2674 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 51,242 psi | 82% | 2635 fps | 99.9% |
| Norma 204 | <<locked>> | 88% | 53,737 psi | 86% | 2694 fps | 99% |
| Norma 217ᴾ | <<locked>> | 100% | 35,520 psi | 57% | 2490 fps | 96.3% |
| Norma MRP | <<locked>> | 94% | 53,272 psi | 85% | 2776 fps | 99.8% |
| Norma URP | <<locked>> | 88% | 54,273 psi | 87% | 2690 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 55,419 psi | 89% | 2802 fps | 99% |
| Ramshot Hunter | <<locked>> | 88% | 53,069 psi | 85% | 2697 fps | 100% |
| Ramshot Magnum | <<locked>> | 98% | 56,391 psi | 90% | 2782 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,695 psi | 60% | 1696 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 55,825 psi | 90% | 2664 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 53,272 psi | 85% | 2707 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 55,506 psi | 89% | 2726 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 53,693 psi | 86% | 2753 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 49,501 psi | 79% | 2785 fps | 99.9% |
| Rottweil R 903 | <<locked>> | 84% | 56,246 psi | 90% | 2657 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 54,215 psi | 87% | 2674 fps | 98.4% |
| Rottweil R 905 | <<locked>> | 94% | 55,245 psi | 89% | 2736 fps | 99.4% |
| Rottweil R 907 | <<locked>> | 86% | 55,172 psi | 88% | 2657 fps | 99.7% |
| Shooters World Long Rifle | <<locked>> | 86% | 53,751 psi | 86% | 2628 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 55,158 psi | 88% | 2674 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 54,186 psi | 87% | 2664 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 53,171 psi | 85% | 2493 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 56,434 psi | 90% | 2635 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 54,810 psi | 88% | 2730 fps | 99.4% |
| Somchem S355 | <<locked>> | 84% | 56,101 psi | 90% | 2651 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 55,695 psi | 89% | 2671 fps | 98% |
| Somchem S365 | <<locked>> | 90% | 54,230 psi | 87% | 2694 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 55,869 psi | 90% | 2710 fps | 99.8% |
| Unknown powder | <<locked>> | 86% | 54,505 psi | 87% | 2690 fps | 100% |
| Vihtavuori N150 | <<locked>> | 84% | 53,708 psi | 86% | 2579 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 56,202 psi | 90% | 2684 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 55,100 psi | 88% | 2687 fps | 99.6% |
| Vihtavuori N550 | <<locked>> | 88% | 55,332 psi | 89% | 2690 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 53,505 psi | 86% | 2707 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 53,345 psi | 86% | 2769 fps | 98% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 52,562 psi | 84% | 2743 fps | 98.1% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 55,448 psi | 89% | 2644 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 54,969 psi | 88% | 2723 fps | 99.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 54,882 psi | 88% | 2858 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 53,548 psi | 86% | 2674 fps | 99.1% |
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 2700 | <<locked>> | 80% | 48,994 psi | 79% | 2520 fps | 99% |
| Accurate 3100 | <<locked>> | 80% | 31,575 psi | 51% | 2260 fps | 96.3% |
| Accurate 4350 | <<locked>> | 80% | 42,540 psi | 68% | 2500 fps | 99.9% |
| Accurate MAGPRO | 72.4 gr | 94% | 49,298 psi | 79% | 2700 fps | 95.8% |
| ADI AR 2208 | <<locked>> | 80% | 50,836 psi | 82% | 2575 fps | 100% |
| ADI AR 2209 | <<locked>> | 82% | 38,058 psi | 61% | 2431 fps | 95.7% |
| ADI AR 2213 | <<locked>> | 88% | 41,408 psi | 66% | 2530 fps | 95.3% |
| ADI AR 2217 | <<locked>> | 98% | 42,308 psi | 68% | 2546 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 94% | 33,069 psi | 53% | 2392 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 51,706 psi | 83% | 2595 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 40,959 psi | 66% | 2507 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 80% | 46,789 psi | 75% | 2618 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 37,942 psi | 61% | 2428 fps | 95.8% |
| Alliant Reloder-22 | <<locked>> | 84% | 35,897 psi | 58% | 2425 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 30,284 psi | 49% | 2290 fps | 99.1% |
| Alliant Reloder-25 | <<locked>> | 82% | 28,297 psi | 45% | 2251 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 80% | 32,605 psi | 52% | 2405 fps | 98.2% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 52,953 psi | 85% | 2671 fps | 95.2% |
| Bofors RP15 | <<locked>> | 88% | 38,101 psi | 61% | 2474 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 52,518 psi | 84% | 2612 fps | 100% |
| Bofors RP30 | <<locked>> | 94% | 37,826 psi | 61% | 2500 fps | 95% |
| Bofors RP5 | <<locked>> | 84% | 35,897 psi | 58% | 2425 fps | 95.2% |
| Bofors RP7 | <<locked>> | 80% | 45,716 psi | 73% | 2503 fps | 98.6% |
| Hodgdon H1000 | <<locked>> | 94% | 38,072 psi | 61% | 2457 fps | 95% |
| Hodgdon H380 | <<locked>> | 80% | 52,518 psi | 84% | 2625 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 47,935 psi | 77% | 2612 fps | 99.4% |
| Hodgdon H4350 | <<locked>> | 80% | 43,163 psi | 69% | 2490 fps | 97.6% |
| Hodgdon H4831 | <<locked>> | 92% | 44,019 psi | 71% | 2533 fps | 95.5% |
| Hodgdon H4831 SC | <<locked>> | 88% | 43,424 psi | 70% | 2520 fps | 95.3% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 38,522 psi | 62% | 2402 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 35,679 psi | 57% | 2490 fps | 95.5% |
| Hodgdon Superformance | <<locked>> | 80% | 43,323 psi | 69% | 2562 fps | 98.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,557 psi | 44% | 1476 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 50,067 psi | 80% | 2552 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,704 psi | 78% | 2533 fps | 99.4% |
| IMR 4350 | <<locked>> | 80% | 41,350 psi | 66% | 2441 fps | 97.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 47,152 psi | 76% | 2530 fps | 99.1% |
| IMR 4831 | <<locked>> | 80% | 36,869 psi | 59% | 2375 fps | 99.3% |
| IMR 4955 Enduron | <<locked>> | 86% | 43,279 psi | 69% | 2484 fps | 95.5% |
| IMR 7828 SSC | <<locked>> | 88% | 42,366 psi | 68% | 2562 fps | 95.8% |
| Lovex S065 | <<locked>> | 80% | 44,643 psi | 72% | 2480 fps | 99.6% |
| Lovex S070 | <<locked>> | 80% | 43,062 psi | 69% | 2474 fps | 98.7% |
| Lovex S071 | <<locked>> | 82% | 29,022 psi | 47% | 2198 fps | 95.2% |
| Norma 204 | <<locked>> | 80% | 41,017 psi | 66% | 2470 fps | 96.5% |
| Norma 217 | <<locked>> | 98% | 33,214 psi | 53% | 2431 fps | 95.3% |
| Norma MRP | 60.5 gr | 80% | 32,750 psi | 53% | 2375 fps | 95.4% |
| Norma URP | <<locked>> | 80% | 42,003 psi | 67% | 2490 fps | 99.8% |
| Ramshot Grand | <<locked>> | 86% | 41,307 psi | 66% | 2556 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 40,741 psi | 65% | 2484 fps | 98.8% |
| Ramshot Magnum | <<locked>> | 86% | 35,853 psi | 57% | 2421 fps | 96% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,181 psi | 45% | 1512 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 52,330 psi | 84% | 2615 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 49,690 psi | 80% | 2657 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 42,351 psi | 68% | 2520 fps | 99.8% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 40,698 psi | 65% | 2533 fps | 99.6% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 32,460 psi | 52% | 2405 fps | 95.2% |
| Rottweil R 903 | <<locked>> | 80% | 49,603 psi | 80% | 2562 fps | 100% |
| Rottweil R 904 | <<locked>> | 82% | 39,552 psi | 63% | 2415 fps | 95% |
| Rottweil R 905 | <<locked>> | 82% | 37,246 psi | 60% | 2415 fps | 95.7% |
| Rottweil R 907 | <<locked>> | 80% | 45,716 psi | 73% | 2503 fps | 98.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 44,643 psi | 72% | 2480 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 80% | 42,888 psi | 69% | 2470 fps | 98.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 50,763 psi | 81% | 2615 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 49,966 psi | 80% | 2451 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 43,671 psi | 70% | 2434 fps | 98.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 36,912 psi | 59% | 2408 fps | 95.6% |
| Somchem S355 | <<locked>> | 80% | 49,458 psi | 79% | 2559 fps | 100% |
| Somchem S361 | <<locked>> | 84% | 42,989 psi | 69% | 2461 fps | 95.1% |
| Somchem S365 | <<locked>> | 80% | 38,696 psi | 62% | 2451 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 35,389 psi | 57% | 2346 fps | 96% |
| Unknown powder | <<locked>> | 80% | 44,962 psi | 72% | 2539 fps | 99.8% |
| Vihtavuori N150 | <<locked>> | 80% | 47,427 psi | 76% | 2490 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 43,352 psi | 70% | 2487 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 84% | 34,925 psi | 56% | 2333 fps | 95.4% |
| Vihtavuori N550 | <<locked>> | 80% | 42,583 psi | 68% | 2487 fps | 99.8% |
| Vihtavuori N555 | <<locked>> | 80% | 33,852 psi | 54% | 2359 fps | 99% |
| Vihtavuori N560 | 66.6 gr | 88% | 43,540 psi | 70% | 2598 fps | 95.7% |
| Vihtavuori N565 | <<locked>> | 94% | 43,062 psi | 69% | 2579 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 42,235 psi | 68% | 2454 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 47,935 psi | 77% | 2612 fps | 99.4% |
| Winchester StaBALL HD | <<locked>> | 80% | 26,847 psi | 43% | 2293 fps | 99% |
| Winchester Supreme 780 | <<locked>> | 82% | 37,666 psi | 60% | 2398 fps | 95.7% |
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 82 powders for .300 Win. Mag. loaded with the .308 | 205gr | Sierra GameKing. Winchester StaBALL HD delivers the highest muzzle velocity at 2,858 fps; across all powders the maximum-charge window runs from 1,657 fps to 2,858 fps. ADI AR 2217 gives the best case fill at 100 %, and 82 of the 82 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 205.0 gr projectile in 0.308" calls for a 1:13.0 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. Norma MRP, Vihtavuori N560, Accurate MAGPRO rank at the top here: for .300 Win. Mag. with the .308 | 205gr | Sierra GameKing 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.