Load Specifications
Load data in caliber .300 H&H Mag. with .308 | 205gr | Sierra GameKing bullet and 86 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 Alliant Reloder-26.
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>> | 82% | 55,622 psi | 89% | 2595 fps | 99.4% |
| Accurate 3100 | <<locked>> | 98% | 54,114 psi | 87% | 2648 fps | 99.9% |
| Accurate 4064 | <<locked>> | 82% | 55,347 psi | 89% | 2575 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 56,202 psi | 90% | 2687 fps | 100% |
| Accurate High Country | <<locked>> | 96% | 55,361 psi | 89% | 2785 fps | 98.5% |
| Accurate MAGPRO | <<locked>> | 98% | 56,362 psi | 90% | 2789 fps | 97.5% |
| ADI AR 2208 | <<locked>> | 84% | 55,013 psi | 88% | 2605 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 53,301 psi | 85% | 2680 fps | 98.8% |
| ADI AR 2213 | <<locked>> | 98% | 54,433 psi | 87% | 2730 fps | 98% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 37,652 psi | 60% | 2477 fps | 97.1% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 53,621 psi | 86% | 2680 fps | 98.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 56,101 psi | 90% | 2628 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 56,072 psi | 90% | 2648 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 53,388 psi | 86% | 2690 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 54,578 psi | 88% | 2707 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 56,202 psi | 90% | 2720 fps | 99.2% |
| Alliant Reloder-22 | <<locked>> | 98% | 53,693 psi | 86% | 2726 fps | 99% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 54,549 psi | 87% | 2707 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 47,195 psi | 76% | 2654 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 96% | 54,708 psi | 88% | 2795 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 52,692 psi | 84% | 2710 fps | 98.8% |
| Bofors RP3 | <<locked>> | 82% | 53,258 psi | 85% | 2595 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 43,163 psi | 69% | 2582 fps | 96.3% |
| Bofors RP5 | <<locked>> | 98% | 53,693 psi | 86% | 2726 fps | 99% |
| Bofors RP7 | <<locked>> | 88% | 55,985 psi | 90% | 2635 fps | 99.6% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 46,862 psi | 75% | 2602 fps | 97.2% |
| Hodgdon H380 | <<locked>> | 82% | 53,447 psi | 86% | 2612 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 54,520 psi | 87% | 2684 fps | 99.7% |
| Hodgdon H4350 | <<locked>> | 86% | 54,157 psi | 87% | 2644 fps | 99.1% |
| Hodgdon H4831 | <<locked>> | 96% | 54,723 psi | 88% | 2677 fps | 97.4% |
| Hodgdon H4831 SC | <<locked>> | 96% | 53,679 psi | 86% | 2664 fps | 97.3% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 53,650 psi | 86% | 2615 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 46,354 psi | 74% | 2700 fps | 98.6% |
| Hodgdon Superformance | <<locked>> | 88% | 54,549 psi | 87% | 2723 fps | 99.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,622 psi | 59% | 1624 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 54,563 psi | 87% | 2589 fps | 100% |
| IMR 4350 | <<locked>> | 90% | 53,780 psi | 86% | 2625 fps | 99.4% |
| IMR 4451 Enduron | <<locked>> | 86% | 54,317 psi | 87% | 2615 fps | 99.6% |
| IMR 4831 | <<locked>> | 90% | 53,026 psi | 85% | 2631 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 56,231 psi | 90% | 2667 fps | 97.9% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 55,753 psi | 89% | 2766 fps | 98.4% |
| Lovex S062 | <<locked>> | 82% | 54,824 psi | 88% | 2582 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 54,389 psi | 87% | 2608 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 55,724 psi | 89% | 2651 fps | 99.8% |
| Lovex S071ᴾ | <<locked>> | 100% | 48,385 psi | 78% | 2562 fps | 99.6% |
| Norma 203B | <<locked>> | 82% | 55,390 psi | 89% | 2635 fps | 100% |
| Norma 204 | <<locked>> | 90% | 54,259 psi | 87% | 2671 fps | 98.8% |
| Norma MRP | <<locked>> | 96% | 53,403 psi | 86% | 2753 fps | 99.7% |
| Norma URP | <<locked>> | 90% | 54,679 psi | 88% | 2667 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 56,246 psi | 90% | 2661 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 56,434 psi | 90% | 2785 fps | 98.7% |
| Ramshot Hunter | <<locked>> | 90% | 53,432 psi | 86% | 2674 fps | 99.9% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 50,343 psi | 81% | 2664 fps | 99.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,478 psi | 60% | 1663 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 53,403 psi | 86% | 2598 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 53,882 psi | 86% | 2694 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 56,115 psi | 90% | 2710 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 54,215 psi | 87% | 2733 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 46,195 psi | 74% | 2690 fps | 99.3% |
| Rottweil R 903 | <<locked>> | 84% | 53,621 psi | 86% | 2595 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 55,114 psi | 88% | 2657 fps | 98.2% |
| Rottweil R 905 | <<locked>> | 96% | 55,593 psi | 89% | 2710 fps | 99.2% |
| Rottweil R 907 | <<locked>> | 88% | 55,985 psi | 90% | 2635 fps | 99.6% |
| Shooters World Long Rifle | <<locked>> | 88% | 54,389 psi | 87% | 2608 fps | 100% |
| Shooters World Precision | <<locked>> | 82% | 54,824 psi | 88% | 2582 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 55,724 psi | 89% | 2651 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 54,998 psi | 88% | 2651 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 54,331 psi | 87% | 2484 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 53,969 psi | 87% | 2569 fps | 99.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 55,129 psi | 88% | 2703 fps | 99.1% |
| Somchem S355 | <<locked>> | 84% | 53,374 psi | 86% | 2589 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 52,953 psi | 85% | 2598 fps | 97% |
| Somchem S365 | <<locked>> | 92% | 54,288 psi | 87% | 2671 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 56,376 psi | 90% | 2690 fps | 99.6% |
| Vihtavuori N150 | <<locked>> | 86% | 54,549 psi | 87% | 2566 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 53,171 psi | 85% | 2615 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 55,622 psi | 89% | 2664 fps | 99.4% |
| Vihtavuori N540 | <<locked>> | 82% | 55,288 psi | 89% | 2562 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 56,014 psi | 90% | 2671 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 53,505 psi | 86% | 2684 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 53,592 psi | 86% | 2743 fps | 97.6% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 49,327 psi | 79% | 2664 fps | 97% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 56,231 psi | 90% | 2631 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 54,781 psi | 88% | 2690 fps | 99.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 50,227 psi | 81% | 2779 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 56,231 psi | 90% | 2684 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% | 51,953 psi | 83% | 2543 fps | 99.1% |
| Accurate 3100 | <<locked>> | 82% | 31,633 psi | 51% | 2241 fps | 95.9% |
| Accurate 4064 | <<locked>> | 80% | 52,127 psi | 84% | 2530 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 40,001 psi | 64% | 2428 fps | 99.5% |
| Accurate High Country | <<locked>> | 88% | 42,032 psi | 67% | 2556 fps | 95.5% |
| Accurate MAGPRO | <<locked>> | 92% | 45,600 psi | 73% | 2612 fps | 95% |
| ADI AR 2208 | <<locked>> | 80% | 48,602 psi | 78% | 2510 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 38,595 psi | 62% | 2415 fps | 95.3% |
| ADI AR 2213 | <<locked>> | 92% | 44,730 psi | 72% | 2566 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 98% | 35,331 psi | 57% | 2418 fps | 96.1% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 38,783 psi | 62% | 2415 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 49,559 psi | 79% | 2536 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 52,576 psi | 84% | 2598 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 38,754 psi | 62% | 2438 fps | 99.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 44,063 psi | 71% | 2549 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 38,392 psi | 62% | 2408 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 88% | 38,653 psi | 62% | 2457 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 28,645 psi | 46% | 2221 fps | 98.3% |
| Alliant Reloder-25 | <<locked>> | 86% | 30,284 psi | 49% | 2280 fps | 95.8% |
| Alliant Reloder-26 | 59.1 gr | 80% | 30,618 psi | 49% | 2329 fps | 96.9% |
| Bofors RP15 | <<locked>> | 90% | 38,145 psi | 61% | 2444 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 49,879 psi | 80% | 2546 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 40,335 psi | 65% | 2526 fps | 95.4% |
| Bofors RP5 | <<locked>> | 88% | 38,653 psi | 62% | 2457 fps | 95.7% |
| Bofors RP7 | <<locked>> | 80% | 43,685 psi | 70% | 2438 fps | 97.9% |
| Hodgdon H1000 | <<locked>> | 96% | 40,959 psi | 66% | 2487 fps | 95.4% |
| Hodgdon H380 | <<locked>> | 80% | 50,082 psi | 80% | 2562 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 41,959 psi | 67% | 2474 fps | 98.1% |
| Hodgdon H4350 | <<locked>> | 80% | 44,643 psi | 72% | 2487 fps | 97.5% |
| Hodgdon H4831 | <<locked>> | 90% | 44,744 psi | 72% | 2516 fps | 95.1% |
| Hodgdon H4831 SC | <<locked>> | 92% | 46,934 psi | 75% | 2556 fps | 95.7% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 36,492 psi | 59% | 2339 fps | 99.8% |
| Hodgdon Retumbo | <<locked>> | 94% | 38,145 psi | 61% | 2520 fps | 95.9% |
| Hodgdon Superformance | <<locked>> | 80% | 40,741 psi | 65% | 2487 fps | 97.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,441 psi | 44% | 1450 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 51,155 psi | 82% | 2539 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 39,407 psi | 63% | 2375 fps | 96.9% |
| IMR 4451 Enduron | <<locked>> | 80% | 45,136 psi | 72% | 2464 fps | 98.5% |
| IMR 4831 | <<locked>> | 80% | 38,435 psi | 62% | 2385 fps | 99.3% |
| IMR 4955 Enduron | <<locked>> | 88% | 43,801 psi | 70% | 2461 fps | 95.1% |
| IMR 7828 SSC | <<locked>> | 92% | 42,844 psi | 69% | 2539 fps | 95.3% |
| Lovex S062 | <<locked>> | 80% | 51,648 psi | 83% | 2539 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 42,772 psi | 69% | 2421 fps | 99.1% |
| Lovex S070 | <<locked>> | 80% | 41,031 psi | 66% | 2408 fps | 98% |
| Lovex S071 | <<locked>> | 86% | 31,024 psi | 50% | 2228 fps | 95.6% |
| Norma 203B | <<locked>> | 80% | 51,967 psi | 83% | 2585 fps | 100% |
| Norma 204 | <<locked>> | 80% | 38,754 psi | 62% | 2398 fps | 95.3% |
| Norma MRP | 58.8 gr | 82% | 33,025 psi | 53% | 2356 fps | 95% |
| Norma URP | <<locked>> | 80% | 39,784 psi | 64% | 2425 fps | 99.4% |
| Ramshot Big Game | <<locked>> | 80% | 52,489 psi | 84% | 2608 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 42,438 psi | 68% | 2546 fps | 95.6% |
| Ramshot Hunter | <<locked>> | 80% | 38,421 psi | 62% | 2411 fps | 97.9% |
| Ramshot Magnum | <<locked>> | 90% | 35,070 psi | 56% | 2372 fps | 95% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,079 psi | 45% | 1486 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 50,125 psi | 80% | 2549 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 46,789 psi | 75% | 2592 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 39,885 psi | 64% | 2451 fps | 99.3% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 38,348 psi | 61% | 2457 fps | 98.9% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 34,998 psi | 56% | 2441 fps | 95.8% |
| Rottweil R 903 | <<locked>> | 80% | 47,195 psi | 76% | 2500 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 42,627 psi | 68% | 2448 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 84% | 37,623 psi | 60% | 2395 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 80% | 43,685 psi | 70% | 2438 fps | 97.9% |
| Shooters World Long Rifle | <<locked>> | 80% | 42,772 psi | 69% | 2421 fps | 99.1% |
| Shooters World Precision | <<locked>> | 80% | 51,648 psi | 83% | 2539 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 41,031 psi | 66% | 2408 fps | 98% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 48,138 psi | 77% | 2549 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 48,080 psi | 77% | 2402 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 41,814 psi | 67% | 2369 fps | 98% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 37,275 psi | 60% | 2392 fps | 95.2% |
| Somchem S355 | <<locked>> | 80% | 47,355 psi | 76% | 2497 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 46,514 psi | 75% | 2493 fps | 95.6% |
| Somchem S365 | <<locked>> | 80% | 36,361 psi | 58% | 2385 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 35,694 psi | 57% | 2329 fps | 95.6% |
| Vihtavuori N150 | <<locked>> | 80% | 45,237 psi | 73% | 2431 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 41,002 psi | 66% | 2418 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 86% | 35,201 psi | 56% | 2313 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 51,895 psi | 83% | 2516 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 40,437 psi | 65% | 2421 fps | 99.3% |
| Vihtavuori N555 | <<locked>> | 80% | 31,865 psi | 51% | 2290 fps | 98.2% |
| Vihtavuori N560 | 64.5 gr | 90% | 43,758 psi | 70% | 2572 fps | 95.2% |
| Vihtavuori N565 | <<locked>> | 96% | 42,917 psi | 69% | 2549 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 39,987 psi | 64% | 2388 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 41,959 psi | 67% | 2474 fps | 98.1% |
| Winchester StaBALL HD | <<locked>> | 80% | 25,222 psi | 40% | 2208 fps | 97.6% |
| Winchester Supreme 780 | <<locked>> | 86% | 37,289 psi | 60% | 2362 fps | 95% |
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 86 powders for .300 H&H Mag. loaded with the .308 | 205gr | Sierra GameKing. Alliant Reloder-26 delivers the highest muzzle velocity at 2,795 fps; across all powders the maximum-charge window runs from 1,624 fps to 2,795 fps. ADI AR 2225 gives the best case fill at 100 %, and 86 of the 86 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 205.0 gr projectile in 0.308" calls for a 1:13.0 twist; slower twists will usually not stabilise this weight. ADI AR 2225, Alliant Reloder-23, 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, Alliant Reloder-26 rank at the top here: for .300 H&H 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.