Load Specifications
Load data in caliber .300 H&H Mag. with .308 | 185gr | Lapua Mega bullet and 90 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Accurate High Country 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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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 2495 | <<locked>> | 82% | 56,260 psi | 90% | 2684 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 53,809 psi | 86% | 2707 fps | 98.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 55,390 psi | 89% | 2805 fps | 99.8% |
| Accurate 4064 | <<locked>> | 82% | 53,258 psi | 85% | 2694 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 54,027 psi | 87% | 2802 fps | 100% |
| Accurate High Country | <<locked>> | 96% | 53,011 psi | 85% | 2890 fps | 97.3% |
| Accurate MAGPRO | <<locked>> | 98% | 53,708 psi | 86% | 2887 fps | 96% |
| ADI AR 2208 | <<locked>> | 84% | 53,287 psi | 85% | 2726 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 54,810 psi | 88% | 2841 fps | 98.3% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 56,101 psi | 90% | 2894 fps | 97.5% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 56,231 psi | 90% | 2897 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 54,984 psi | 88% | 2841 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 54,114 psi | 87% | 2749 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 54,172 psi | 87% | 2766 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 54,752 psi | 88% | 2854 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 55,941 psi | 90% | 2877 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 54,302 psi | 87% | 2831 fps | 98.3% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 55,056 psi | 88% | 2890 fps | 98.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 52,170 psi | 84% | 2822 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,208 psi | 72% | 2749 fps | 99.4% |
| Alliant Reloder-26 | <<locked>> | 98% | 56,086 psi | 90% | 2959 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 50,647 psi | 81% | 2815 fps | 97.7% |
| Bofors RP3 | <<locked>> | 84% | 54,853 psi | 88% | 2762 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 55,056 psi | 88% | 2890 fps | 98.6% |
| Bofors RP7 | <<locked>> | 88% | 54,331 psi | 87% | 2753 fps | 98.9% |
| Hodgdon H380 | <<locked>> | 84% | 55,245 psi | 89% | 2782 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 55,927 psi | 90% | 2848 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 88% | 55,724 psi | 89% | 2808 fps | 98.7% |
| Hodgdon H4831 | <<locked>> | 98% | 56,231 psi | 90% | 2838 fps | 96.8% |
| Hodgdon H4831 SC | <<locked>> | 98% | 55,172 psi | 88% | 2822 fps | 96.6% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 54,926 psi | 88% | 2779 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 56,333 psi | 90% | 2812 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 44,295 psi | 71% | 2782 fps | 96.9% |
| Hodgdon Superformance | <<locked>> | 90% | 56,362 psi | 90% | 2890 fps | 99.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,593 psi | 59% | 1726 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,115 psi | 90% | 2756 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 55,129 psi | 88% | 2743 fps | 99.3% |
| IMR 4350 | <<locked>> | 92% | 55,085 psi | 88% | 2782 fps | 99.1% |
| IMR 4451 Enduron | <<locked>> | 88% | 55,883 psi | 90% | 2779 fps | 99.4% |
| IMR 4831 | <<locked>> | 92% | 54,433 psi | 87% | 2792 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 55,550 psi | 89% | 2792 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 54,288 psi | 87% | 2772 fps | 96.6% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 53,403 psi | 86% | 2864 fps | 97.1% |
| Lovex S062 | <<locked>> | 84% | 56,275 psi | 90% | 2749 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,072 psi | 90% | 2776 fps | 99.9% |
| Lovex S070 | <<locked>> | 90% | 53,998 psi | 87% | 2766 fps | 99.4% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,050 psi | 74% | 2657 fps | 98.8% |
| Norma 203B | <<locked>> | 82% | 53,490 psi | 86% | 2753 fps | 100% |
| Norma 204 | <<locked>> | 92% | 55,854 psi | 90% | 2835 fps | 98.3% |
| Norma MRP | <<locked>> | 98% | 54,839 psi | 88% | 2917 fps | 99.4% |
| Norma URP | <<locked>> | 92% | 56,275 psi | 90% | 2838 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 54,302 psi | 87% | 2782 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 53,853 psi | 86% | 2881 fps | 97.5% |
| Ramshot Hunter | <<locked>> | 92% | 54,839 psi | 88% | 2838 fps | 99.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 48,138 psi | 77% | 2759 fps | 98% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,144 psi | 60% | 1765 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,114 psi | 88% | 2766 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 55,390 psi | 89% | 2867 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 53,621 psi | 86% | 2822 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 55,941 psi | 90% | 2907 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 44,295 psi | 71% | 2779 fps | 98% |
| Rottweil R 902 | <<locked>> | 82% | 54,839 psi | 88% | 2713 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 54,955 psi | 88% | 2759 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 53,055 psi | 85% | 2762 fps | 97% |
| Rottweil R 905 | <<locked>> | 96% | 53,345 psi | 86% | 2815 fps | 98.3% |
| Rottweil R 907 | <<locked>> | 88% | 54,331 psi | 87% | 2753 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,072 psi | 90% | 2776 fps | 99.9% |
| Shooters World Precision | <<locked>> | 84% | 56,275 psi | 90% | 2749 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 53,998 psi | 87% | 2766 fps | 99.4% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 52,881 psi | 85% | 2766 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 55,738 psi | 89% | 2644 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 55,622 psi | 89% | 2730 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 52,881 psi | 85% | 2812 fps | 98.2% |
| Somchem S355 | <<locked>> | 86% | 55,013 psi | 88% | 2756 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 54,520 psi | 87% | 2753 fps | 96.4% |
| Somchem S365 | <<locked>> | 94% | 55,767 psi | 89% | 2841 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 54,085 psi | 87% | 2795 fps | 98.9% |
| Vihtavuori N135 | <<locked>> | 82% | 55,230 psi | 89% | 2671 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 55,477 psi | 89% | 2687 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,072 psi | 90% | 2730 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 54,795 psi | 88% | 2782 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 53,272 psi | 85% | 2769 fps | 98.6% |
| Vihtavuori N540 | <<locked>> | 82% | 53,577 psi | 86% | 2684 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 53,940 psi | 86% | 2785 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 54,578 psi | 88% | 2844 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 55,129 psi | 88% | 2907 fps | 97% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 54,230 psi | 87% | 2746 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 56,188 psi | 90% | 2854 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 47,326 psi | 76% | 2884 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 54,114 psi | 87% | 2789 fps | 98.2% |
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 2495 | <<locked>> | 80% | 52,736 psi | 85% | 2638 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 50,401 psi | 81% | 2654 fps | 98.2% |
| Accurate 3100 | <<locked>> | 84% | 32,343 psi | 52% | 2375 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 49,980 psi | 80% | 2648 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,363 psi | 62% | 2523 fps | 98.6% |
| Accurate High Country | 68.9 gr | 92% | 46,064 psi | 74% | 2766 fps | 95.6% |
| Accurate MAGPRO | <<locked>> | 96% | 50,067 psi | 80% | 2825 fps | 95.1% |
| ADI AR 2208 | <<locked>> | 80% | 47,094 psi | 76% | 2625 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 42,279 psi | 68% | 2618 fps | 95.4% |
| ADI AR 2213 | <<locked>> | 96% | 49,052 psi | 79% | 2772 fps | 95.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 52,228 psi | 84% | 2838 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 42,351 psi | 68% | 2618 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 47,805 psi | 77% | 2651 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 50,937 psi | 82% | 2717 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,260 psi | 60% | 2533 fps | 98.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,293 psi | 68% | 2654 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 41,887 psi | 67% | 2608 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 92% | 42,206 psi | 68% | 2657 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,340 psi | 44% | 2293 fps | 96.5% |
| Alliant Reloder-25 | <<locked>> | 90% | 32,967 psi | 53% | 2467 fps | 95.8% |
| Alliant Reloder-26 | 63.2 gr | 82% | 31,256 psi | 50% | 2461 fps | 95.9% |
| Bofors RP15 | <<locked>> | 94% | 41,626 psi | 67% | 2644 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 48,109 psi | 77% | 2661 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 42,206 psi | 68% | 2657 fps | 95.7% |
| Bofors RP7 | <<locked>> | 80% | 42,221 psi | 68% | 2536 fps | 96.6% |
| Hodgdon H380 | <<locked>> | 80% | 48,341 psi | 78% | 2671 fps | 99.7% |
| Hodgdon H414 | <<locked>> | 80% | 40,263 psi | 65% | 2572 fps | 96.7% |
| Hodgdon H4350 | <<locked>> | 80% | 43,105 psi | 69% | 2589 fps | 96.1% |
| Hodgdon H4831 | <<locked>> | 94% | 49,153 psi | 79% | 2723 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 94% | 48,283 psi | 77% | 2707 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,795 psi | 56% | 2431 fps | 99.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 52,721 psi | 85% | 2759 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 41,611 psi | 67% | 2720 fps | 96% |
| Hodgdon Superformance | <<locked>> | 80% | 39,088 psi | 63% | 2579 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,238 psi | 44% | 1539 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,545 psi | 79% | 2657 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 51,619 psi | 83% | 2684 fps | 98.9% |
| IMR 4350 | <<locked>> | 80% | 37,942 psi | 61% | 2467 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 43,642 psi | 70% | 2569 fps | 97.4% |
| IMR 4831 | <<locked>> | 80% | 36,811 psi | 59% | 2477 fps | 98.3% |
| IMR 4895 | <<locked>> | 80% | 52,243 psi | 84% | 2743 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 47,819 psi | 77% | 2664 fps | 95.1% |
| IMR 7828 SSC | <<locked>> | 96% | 46,891 psi | 75% | 2746 fps | 95.4% |
| Lovex S062 | <<locked>> | 80% | 49,748 psi | 80% | 2651 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,118 psi | 66% | 2516 fps | 98.1% |
| Lovex S070 | <<locked>> | 80% | 39,494 psi | 63% | 2500 fps | 96.7% |
| Lovex S071 | <<locked>> | 90% | 33,605 psi | 54% | 2405 fps | 95.5% |
| Norma 203B | <<locked>> | 80% | 50,285 psi | 81% | 2703 fps | 100% |
| Norma 204 | <<locked>> | 84% | 42,685 psi | 68% | 2605 fps | 95.4% |
| Norma MRP | 64.4 gr | 86% | 36,187 psi | 58% | 2556 fps | 95.1% |
| Norma URP | <<locked>> | 80% | 38,130 psi | 61% | 2520 fps | 98.5% |
| Ramshot Big Game | <<locked>> | 80% | 50,575 psi | 81% | 2723 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 46,847 psi | 75% | 2756 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 36,941 psi | 59% | 2507 fps | 96.6% |
| Ramshot Magnum | <<locked>> | 94% | 38,798 psi | 62% | 2575 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,818 psi | 45% | 1578 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,370 psi | 78% | 2657 fps | 98.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 44,904 psi | 72% | 2707 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,014 psi | 61% | 2539 fps | 98.3% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 36,825 psi | 59% | 2546 fps | 97.7% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 38,450 psi | 62% | 2641 fps | 95.9% |
| Rottweil R 902 | <<locked>> | 80% | 51,547 psi | 83% | 2664 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,411 psi | 73% | 2612 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 46,601 psi | 75% | 2651 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 88% | 40,944 psi | 66% | 2592 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 80% | 42,221 psi | 68% | 2536 fps | 96.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,118 psi | 66% | 2516 fps | 98.1% |
| Shooters World Precision | <<locked>> | 80% | 49,748 psi | 80% | 2651 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,494 psi | 63% | 2500 fps | 96.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,514 psi | 75% | 2664 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,514 psi | 75% | 2516 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,263 psi | 65% | 2464 fps | 96.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 40,567 psi | 65% | 2585 fps | 95.2% |
| Somchem S355 | <<locked>> | 80% | 45,469 psi | 73% | 2605 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 51,126 psi | 82% | 2700 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 34,606 psi | 55% | 2477 fps | 99.8% |
| Somchem S385 | <<locked>> | 86% | 39,131 psi | 63% | 2526 fps | 95.7% |
| Vihtavuori N135 | <<locked>> | 80% | 52,054 psi | 83% | 2628 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 52,156 psi | 84% | 2641 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,569 psi | 70% | 2539 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,479 psi | 63% | 2516 fps | 98.7% |
| Vihtavuori N165 | <<locked>> | 90% | 38,479 psi | 62% | 2503 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 50,227 psi | 81% | 2635 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 38,841 psi | 62% | 2516 fps | 98.4% |
| Vihtavuori N555 | <<locked>> | 80% | 30,284 psi | 49% | 2372 fps | 96.7% |
| Vihtavuori N560 | <<locked>> | 94% | 48,066 psi | 77% | 2785 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,609 psi | 62% | 2490 fps | 99.8% |
| Winchester 760 | <<locked>> | 80% | 40,263 psi | 65% | 2572 fps | 96.7% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,236 psi | 39% | 2264 fps | 95% |
| Winchester Supreme 780 | <<locked>> | 90% | 40,973 psi | 66% | 2559 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 90 powders for .300 H&H Mag. loaded with the .308 | 185gr | Lapua Mega. Alliant Reloder-26 delivers the highest muzzle velocity at 2,959 fps; across all powders the maximum-charge window runs from 1,726 fps to 2,959 fps. Accurate 3100 gives the best case fill at 100 %, and 90 of the 90 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 59–90 %, 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. Accurate 3100, ADI AR 2213, Alliant Reloder-22 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, Accurate High Country, Norma MRP rank at the top here: for .300 H&H 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.