Load Specifications
Load data in caliber .300 Win. Mag. with .308 | 181gr | RWS H-Mantel bullet and 89 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Norma MRP and ReloadSwiss RS 70.
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.
A valid access license is required to use the Personalized Load Calculator.
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>> | 86% | 55,608 psi | 89% | 2776 fps | 99% |
| Accurate 3100ᴾ | <<locked>> | 100% | 56,289 psi | 90% | 2867 fps | 99.9% |
| Accurate 4064 | <<locked>> | 82% | 53,925 psi | 86% | 2753 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 54,607 psi | 88% | 2861 fps | 100% |
| ADI AR 2208 | <<locked>> | 84% | 53,650 psi | 86% | 2782 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 55,608 psi | 89% | 2907 fps | 98.5% |
| ADI AR 2213 | <<locked>> | 98% | 53,127 psi | 85% | 2897 fps | 97% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 54,708 psi | 88% | 2808 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 54,795 psi | 88% | 2828 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 55,288 psi | 89% | 2917 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 52,953 psi | 85% | 2884 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 54,766 psi | 88% | 2890 fps | 98.4% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 55,927 psi | 90% | 2953 fps | 98.7% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 52,910 psi | 85% | 2881 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,919 psi | 74% | 2812 fps | 99.5% |
| Alliant Reloder-26 | <<locked>> | 96% | 52,982 psi | 85% | 2966 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 51,256 psi | 82% | 2874 fps | 97.9% |
| Bofors RP3 | <<locked>> | 84% | 55,361 psi | 89% | 2822 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 55,927 psi | 90% | 2953 fps | 98.7% |
| Bofors RP7 | <<locked>> | 88% | 54,694 psi | 88% | 2808 fps | 99% |
| Hodgdon H380 | <<locked>> | 84% | 55,709 psi | 89% | 2838 fps | 100% |
| Hodgdon H414 | <<locked>> | 86% | 54,215 psi | 87% | 2874 fps | 99.4% |
| Hodgdon H4350 | <<locked>> | 90% | 54,810 psi | 88% | 2848 fps | 98.6% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 52,359 psi | 84% | 2828 fps | 96.1% |
| Hodgdon H4831 SC | <<locked>> | 98% | 55,767 psi | 89% | 2884 fps | 96.8% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 55,709 psi | 89% | 2838 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 53,766 psi | 86% | 2825 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 44,976 psi | 72% | 2848 fps | 97.3% |
| Hodgdon Superformance | <<locked>> | 88% | 53,069 psi | 85% | 2890 fps | 99.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,564 psi | 59% | 1762 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 53,258 psi | 85% | 2772 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 56,144 psi | 90% | 2789 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 55,999 psi | 90% | 2805 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 54,940 psi | 88% | 2789 fps | 99.4% |
| IMR 4350 | <<locked>> | 92% | 55,767 psi | 89% | 2844 fps | 99.2% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,246 psi | 90% | 2835 fps | 99.4% |
| IMR 4831 | <<locked>> | 96% | 55,883 psi | 90% | 2864 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 56,202 psi | 90% | 2854 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 55,013 psi | 88% | 2835 fps | 96.9% |
| IMR 7828 SSC | <<locked>> | 98% | 54,708 psi | 88% | 2936 fps | 97.4% |
| Lovex S062 | <<locked>> | 82% | 53,374 psi | 86% | 2759 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 53,156 psi | 85% | 2782 fps | 99.8% |
| Lovex S070 | <<locked>> | 90% | 54,505 psi | 87% | 2825 fps | 99.5% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,862 psi | 75% | 2720 fps | 99% |
| Norma 203B | <<locked>> | 82% | 54,099 psi | 87% | 2812 fps | 100% |
| Norma 204 | <<locked>> | 90% | 53,026 psi | 85% | 2841 fps | 97.9% |
| Norma MRP | <<locked>> | 98% | 55,695 psi | 89% | 2982 fps | 99.6% |
| Norma URP | <<locked>> | 90% | 53,345 psi | 86% | 2844 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 54,708 psi | 88% | 2838 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 54,317 psi | 87% | 2943 fps | 97.7% |
| Ramshot Hunter | <<locked>> | 92% | 55,637 psi | 89% | 2900 fps | 99.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 55,158 psi | 88% | 2923 fps | 99.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,304 psi | 60% | 1804 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,651 psi | 89% | 2825 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 56,246 psi | 90% | 2930 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 54,476 psi | 87% | 2884 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 52,721 psi | 85% | 2907 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 44,904 psi | 72% | 2841 fps | 98.3% |
| Rottweil R 902 | <<locked>> | 82% | 55,317 psi | 89% | 2769 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 55,695 psi | 89% | 2822 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 53,650 psi | 86% | 2818 fps | 97.2% |
| Rottweil R 905 | <<locked>> | 96% | 54,143 psi | 87% | 2877 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 88% | 54,694 psi | 88% | 2808 fps | 99% |
| Shooters World Long Rifle | <<locked>> | 88% | 53,156 psi | 85% | 2782 fps | 99.8% |
| Shooters World Precision | <<locked>> | 82% | 53,374 psi | 86% | 2759 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 54,505 psi | 87% | 2825 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 53,563 psi | 86% | 2825 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 56,333 psi | 90% | 2700 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 56,057 psi | 90% | 2785 fps | 99.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 53,664 psi | 86% | 2874 fps | 98.4% |
| Somchem S355 | <<locked>> | 86% | 55,579 psi | 89% | 2815 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 55,303 psi | 89% | 2815 fps | 96.7% |
| Somchem S365 | <<locked>> | 92% | 52,736 psi | 85% | 2848 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 54,795 psi | 88% | 2858 fps | 99.1% |
| Unknown powder | <<locked>> | 88% | 53,780 psi | 86% | 2848 fps | 100% |
| Vihtavuori N133 | <<locked>> | 82% | 55,622 psi | 89% | 2680 fps | 100% |
| Vihtavuori N135 | <<locked>> | 82% | 55,782 psi | 89% | 2726 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 55,172 psi | 88% | 2736 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 53,635 psi | 86% | 2749 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 54,273 psi | 87% | 2822 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 52,214 psi | 84% | 2802 fps | 98.5% |
| Vihtavuori N540 | <<locked>> | 82% | 54,984 psi | 88% | 2762 fps | 100% |
| Vihtavuori N550 | <<locked>> | 88% | 54,578 psi | 88% | 2864 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 55,463 psi | 89% | 2907 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 56,188 psi | 90% | 2979 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 54,926 psi | 88% | 2805 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 54,215 psi | 87% | 2874 fps | 99.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 48,211 psi | 77% | 2946 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 52,692 psi | 84% | 2815 fps | 98% |
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% | 45,745 psi | 73% | 2612 fps | 97.4% |
| Accurate 3100 | <<locked>> | 84% | 32,793 psi | 53% | 2431 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 50,546 psi | 81% | 2703 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,812 psi | 62% | 2579 fps | 98.7% |
| ADI AR 2208 | <<locked>> | 80% | 47,543 psi | 76% | 2680 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 42,786 psi | 69% | 2674 fps | 95.7% |
| ADI AR 2213 | <<locked>> | 94% | 46,456 psi | 74% | 2776 fps | 95.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 48,283 psi | 77% | 2707 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 51,343 psi | 82% | 2772 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,710 psi | 60% | 2592 fps | 98.8% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,786 psi | 69% | 2713 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 42,395 psi | 68% | 2667 fps | 95.7% |
| Alliant Reloder-22 | <<locked>> | 90% | 40,016 psi | 64% | 2661 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,644 psi | 44% | 2349 fps | 96.8% |
| Alliant Reloder-25 | <<locked>> | 88% | 31,415 psi | 50% | 2467 fps | 95% |
| Alliant Reloder-26 | 63.5 gr | 80% | 29,515 psi | 47% | 2454 fps | 95% |
| Bofors RP15 | <<locked>> | 94% | 42,177 psi | 68% | 2707 fps | 95.6% |
| Bofors RP3 | <<locked>> | 80% | 48,718 psi | 78% | 2720 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 40,016 psi | 64% | 2661 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 42,612 psi | 68% | 2592 fps | 96.8% |
| Hodgdon H380 | <<locked>> | 80% | 48,921 psi | 78% | 2730 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 80% | 44,164 psi | 71% | 2697 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 80% | 40,001 psi | 64% | 2572 fps | 95.2% |
| Hodgdon H4831 | <<locked>> | 98% | 49,182 psi | 79% | 2772 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 94% | 48,747 psi | 78% | 2766 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,244 psi | 57% | 2484 fps | 99.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 50,343 psi | 81% | 2772 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 39,465 psi | 63% | 2717 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 39,523 psi | 63% | 2635 fps | 96.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,296 psi | 44% | 1572 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 50,140 psi | 80% | 2723 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 52,924 psi | 85% | 2746 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 46,630 psi | 75% | 2657 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,745 psi | 73% | 2631 fps | 98.1% |
| IMR 4350 | <<locked>> | 80% | 38,276 psi | 61% | 2523 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,019 psi | 71% | 2621 fps | 97.6% |
| IMR 4831 | <<locked>> | 80% | 33,837 psi | 54% | 2454 fps | 97.5% |
| IMR 4895 | <<locked>> | 80% | 52,663 psi | 84% | 2799 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 48,414 psi | 78% | 2723 fps | 95.4% |
| IMR 7828 SSC | <<locked>> | 94% | 47,543 psi | 76% | 2808 fps | 95.7% |
| Lovex S062 | <<locked>> | 80% | 50,285 psi | 81% | 2710 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,553 psi | 67% | 2572 fps | 98.3% |
| Lovex S070 | <<locked>> | 80% | 39,871 psi | 64% | 2556 fps | 96.9% |
| Lovex S071 | <<locked>> | 90% | 33,982 psi | 54% | 2457 fps | 95.8% |
| Norma 203B | <<locked>> | 80% | 50,734 psi | 81% | 2762 fps | 100% |
| Norma 204 | <<locked>> | 84% | 43,250 psi | 69% | 2664 fps | 95.7% |
| Norma MRP | 66.3 gr | 86% | 36,622 psi | 59% | 2612 fps | 95.4% |
| Norma URP | <<locked>> | 80% | 38,537 psi | 62% | 2575 fps | 98.6% |
| Ramshot Big Game | <<locked>> | 80% | 51,285 psi | 82% | 2785 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 46,963 psi | 75% | 2812 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 37,260 psi | 60% | 2559 fps | 96.8% |
| Ramshot Magnum | <<locked>> | 92% | 40,582 psi | 65% | 2661 fps | 96% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,862 psi | 45% | 1611 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,849 psi | 78% | 2717 fps | 99% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,411 psi | 73% | 2766 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,479 psi | 62% | 2595 fps | 98.4% |
| ReloadSwiss RS 70 | 63 gr | 80% | 37,347 psi | 60% | 2605 fps | 97.9% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 36,347 psi | 58% | 2635 fps | 95% |
| Rottweil R 902 | <<locked>> | 80% | 52,098 psi | 84% | 2723 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,861 psi | 74% | 2667 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 47,297 psi | 76% | 2710 fps | 95.7% |
| Rottweil R 905 | <<locked>> | 88% | 41,481 psi | 67% | 2651 fps | 95.6% |
| Rottweil R 907 | <<locked>> | 80% | 42,612 psi | 68% | 2592 fps | 96.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,553 psi | 67% | 2572 fps | 98.3% |
| Shooters World Precision | <<locked>> | 80% | 50,285 psi | 81% | 2710 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,871 psi | 64% | 2556 fps | 96.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,847 psi | 75% | 2717 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,833 psi | 75% | 2569 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,625 psi | 65% | 2520 fps | 96.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 41,104 psi | 66% | 2644 fps | 95.4% |
| Somchem S355 | <<locked>> | 80% | 45,963 psi | 74% | 2664 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 48,327 psi | 77% | 2697 fps | 95.1% |
| Somchem S365 | <<locked>> | 80% | 35,012 psi | 56% | 2533 fps | 99.9% |
| Somchem S385 | <<locked>> | 84% | 36,985 psi | 59% | 2523 fps | 95% |
| Unknown powder | <<locked>> | 80% | 41,408 psi | 66% | 2628 fps | 98.7% |
| Vihtavuori N133 | <<locked>> | 80% | 52,344 psi | 84% | 2635 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 52,460 psi | 84% | 2684 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 51,953 psi | 83% | 2690 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 39,523 psi | 63% | 2513 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 41,452 psi | 66% | 2602 fps | 99.1% |
| Vihtavuori N165 | <<locked>> | 92% | 40,132 psi | 64% | 2585 fps | 95.7% |
| Vihtavuori N540 | <<locked>> | 80% | 51,605 psi | 83% | 2713 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 42,105 psi | 68% | 2644 fps | 99.1% |
| Vihtavuori N555 | <<locked>> | 80% | 30,705 psi | 49% | 2425 fps | 96.9% |
| Vihtavuori N560 | <<locked>> | 96% | 49,168 psi | 79% | 2858 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,914 psi | 62% | 2543 fps | 99.9% |
| Winchester 760 | <<locked>> | 80% | 44,164 psi | 71% | 2697 fps | 97.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,439 psi | 39% | 2316 fps | 95.4% |
| Winchester Supreme 780 | <<locked>> | 88% | 42,685 psi | 68% | 2641 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 98 powders for .300 Win. Mag. loaded with the .308 | 181gr | RWS H-Mantel. Norma MRP delivers the highest muzzle velocity at 2,982 fps; across all powders the maximum-charge window runs from 1,762 fps to 2,982 fps. Accurate 3100 gives the best case fill at 100 %, and 98 of the 98 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 52–90 %, leaving at least 10 % headroom. The 181.0 gr projectile in 0.308" calls for a 1:14.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2217 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. Alliant Reloder-26, Norma MRP, ReloadSwiss RS 70 rank at the top here: for .300 Win. Mag. with the .308 | 181gr | RWS H-Mantel they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2217, Baschieri & Pellagri 109, Bofors RP30 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.