Load Specifications
Load data in caliber .300 H&H Mag. with .308 | 168gr | Sellier & Bellot HPBT bullet and 97 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Hodgdon Superformance and Alliant Reloder-17.
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>> | 84% | 54,549 psi | 87% | 2792 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 56,231 psi | 90% | 2854 fps | 98.1% |
| Accurate 3100ᴾ | <<locked>> | 100% | 49,153 psi | 79% | 2825 fps | 98.5% |
| Accurate 4064 | <<locked>> | 86% | 54,897 psi | 88% | 2848 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 55,201 psi | 89% | 2943 fps | 99.9% |
| ADI AR 2206H | <<locked>> | 82% | 54,230 psi | 87% | 2871 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 55,347 psi | 89% | 2877 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 56,376 psi | 90% | 2976 fps | 97.4% |
| ADI Benchmark 8208 | <<locked>> | 82% | 56,420 psi | 90% | 2871 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 54,128 psi | 87% | 2992 fps | 100% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 56,289 psi | 90% | 2972 fps | 97.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 55,869 psi | 90% | 2900 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 56,188 psi | 90% | 2920 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 96% | 55,796 psi | 89% | 2995 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 53,563 psi | 86% | 2972 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 55,448 psi | 89% | 2963 fps | 97.4% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 48,863 psi | 78% | 2897 fps | 96.1% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 46,195 psi | 74% | 2848 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 40,422 psi | 65% | 2749 fps | 97.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 52,562 psi | 84% | 3031 fps | 99.8% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 53,838 psi | 86% | 2884 fps | 99.9% |
| Bofors RP3 | <<locked>> | 86% | 52,968 psi | 85% | 2861 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 48,863 psi | 78% | 2897 fps | 96.1% |
| Bofors RP7 | <<locked>> | 92% | 56,202 psi | 90% | 2894 fps | 98.3% |
| Hodgdon BL-C2 | <<locked>> | 82% | 56,159 psi | 90% | 2900 fps | 100% |
| Hodgdon H380 | <<locked>> | 86% | 53,650 psi | 86% | 2874 fps | 99.6% |
| Hodgdon H414 | <<locked>> | 92% | 54,012 psi | 87% | 2936 fps | 98.5% |
| Hodgdon H4350 | <<locked>> | 90% | 54,128 psi | 87% | 2897 fps | 97.4% |
| Hodgdon H4895 | <<locked>> | 82% | 54,795 psi | 88% | 2881 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 55,985 psi | 90% | 2920 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 54,694 psi | 88% | 2917 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 54,056 psi | 87% | 2972 fps | 98.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,071 psi | 58% | 1791 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 55,825 psi | 90% | 2884 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 55,100 psi | 88% | 2858 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 54,737 psi | 88% | 2858 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 54,056 psi | 87% | 2835 fps | 98.4% |
| IMR 4350 | <<locked>> | 94% | 53,374 psi | 86% | 2867 fps | 97.9% |
| IMR 4451 Enduron | <<locked>> | 90% | 54,433 psi | 87% | 2867 fps | 98.4% |
| IMR 4831 | <<locked>> | 96% | 55,448 psi | 89% | 2930 fps | 99.9% |
| IMR 4895 | <<locked>> | 84% | 54,172 psi | 87% | 2897 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 56,420 psi | 90% | 2871 fps | 100% |
| Lovex D073.6 | <<locked>> | 82% | 54,273 psi | 87% | 2844 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 53,229 psi | 85% | 2795 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 54,752 psi | 88% | 2851 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 54,418 psi | 87% | 2867 fps | 99.3% |
| Lovex S070 | <<locked>> | 94% | 55,564 psi | 89% | 2907 fps | 98.8% |
| Lovex S071ᴾ | <<locked>> | 100% | 40,799 psi | 65% | 2671 fps | 96.6% |
| Norma 201 | <<locked>> | 84% | 56,362 psi | 90% | 2867 fps | 100% |
| Norma 202 | <<locked>> | 82% | 53,490 psi | 86% | 2815 fps | 100% |
| Norma 203B | <<locked>> | 86% | 55,477 psi | 89% | 2907 fps | 100% |
| Norma 204 | <<locked>> | 94% | 53,925 psi | 86% | 2917 fps | 96.9% |
| Norma MRPᴾ | <<locked>> | 100% | 51,793 psi | 83% | 2986 fps | 98.2% |
| Norma URP | <<locked>> | 94% | 54,027 psi | 87% | 2927 fps | 99.8% |
| Ramshot Big Game | <<locked>> | 86% | 56,144 psi | 90% | 2930 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 56,391 psi | 90% | 2979 fps | 99.4% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,767 psi | 59% | 1834 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 53,679 psi | 86% | 2858 fps | 98.8% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 53,214 psi | 85% | 2930 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 53,098 psi | 85% | 2966 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 54,810 psi | 88% | 2963 fps | 99.8% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 53,737 psi | 86% | 2989 fps | 99.7% |
| Rottweil R 902 | <<locked>> | 84% | 53,650 psi | 86% | 2815 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 53,084 psi | 85% | 2858 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 54,563 psi | 87% | 2890 fps | 95.9% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 54,418 psi | 87% | 2946 fps | 97.4% |
| Rottweil R 907 | <<locked>> | 92% | 56,202 psi | 90% | 2894 fps | 98.3% |
| Shooters World Long Rifle | <<locked>> | 92% | 54,418 psi | 87% | 2867 fps | 99.3% |
| Shooters World Match Rifle | <<locked>> | 82% | 54,273 psi | 87% | 2844 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 54,752 psi | 88% | 2851 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 55,564 psi | 89% | 2907 fps | 98.8% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 54,665 psi | 88% | 2917 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 55,129 psi | 88% | 2871 fps | 99.7% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 56,072 psi | 90% | 2894 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 53,838 psi | 86% | 2749 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 54,549 psi | 87% | 2753 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 54,186 psi | 87% | 2815 fps | 98.4% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 53,911 psi | 86% | 2940 fps | 97.2% |
| Somchem S335 | <<locked>> | 82% | 53,534 psi | 86% | 2749 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 54,853 psi | 88% | 2858 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 53,171 psi | 85% | 2851 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 56,333 psi | 90% | 2979 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 55,143 psi | 88% | 2923 fps | 98.2% |
| Vihtavuori N133 | <<locked>> | 82% | 54,259 psi | 87% | 2733 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 53,751 psi | 86% | 2779 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 54,027 psi | 87% | 2792 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 54,563 psi | 87% | 2831 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 56,304 psi | 90% | 2923 fps | 99.9% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 47,645 psi | 76% | 2785 fps | 96.3% |
| Vihtavuori N540 | <<locked>> | 86% | 55,782 psi | 89% | 2838 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 55,230 psi | 89% | 2927 fps | 99.8% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 51,547 psi | 83% | 2923 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 56,086 psi | 90% | 2894 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 54,012 psi | 87% | 2936 fps | 98.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 41,611 psi | 67% | 2887 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 56,246 psi | 90% | 2904 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 51,851 psi | 83% | 2861 fps | 96.5% |
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% | 47,819 psi | 77% | 2694 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 46,137 psi | 74% | 2684 fps | 96.1% |
| Accurate 3100 | <<locked>> | 92% | 37,405 psi | 60% | 2598 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 45,223 psi | 73% | 2697 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,098 psi | 55% | 2536 fps | 96.2% |
| ADI AR 2206H | <<locked>> | 80% | 50,879 psi | 82% | 2818 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 43,149 psi | 69% | 2664 fps | 99% |
| ADI AR 2209 | <<locked>> | 94% | 46,311 psi | 74% | 2799 fps | 95% |
| ADI Benchmark 8208 | <<locked>> | 80% | 52,982 psi | 85% | 2818 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 46,992 psi | 75% | 2867 fps | 99.6% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 46,354 psi | 74% | 2802 fps | 95.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 43,279 psi | 69% | 2687 fps | 99.8% |
| Alliant Reloder-15 | <<locked>> | 80% | 46,470 psi | 75% | 2759 fps | 99.5% |
| Alliant Reloder-16 | <<locked>> | 80% | 33,678 psi | 54% | 2546 fps | 96.3% |
| Alliant Reloder-17 | 58.8 gr | 80% | 37,840 psi | 61% | 2677 fps | 99.1% |
| Alliant Reloder-19 | <<locked>> | 94% | 45,774 psi | 73% | 2792 fps | 95.1% |
| Alliant Reloder-22 | <<locked>> | 98% | 45,759 psi | 73% | 2838 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 84% | 27,847 psi | 45% | 2405 fps | 95.2% |
| Alliant Reloder-25 | <<locked>> | 96% | 35,650 psi | 57% | 2631 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 88% | 34,171 psi | 55% | 2641 fps | 95.6% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 50,386 psi | 81% | 2828 fps | 99.7% |
| Bofors RP3 | <<locked>> | 80% | 43,511 psi | 70% | 2700 fps | 99.8% |
| Bofors RP5 | <<locked>> | 98% | 45,759 psi | 73% | 2838 fps | 95.3% |
| Bofors RP7 | <<locked>> | 84% | 43,816 psi | 70% | 2674 fps | 95.7% |
| Hodgdon BL-C2 | <<locked>> | 80% | 52,518 psi | 84% | 2844 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 44,005 psi | 71% | 2707 fps | 98.4% |
| Hodgdon H414 | <<locked>> | 84% | 41,321 psi | 66% | 2700 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 84% | 44,585 psi | 71% | 2723 fps | 95.1% |
| Hodgdon H4895 | <<locked>> | 80% | 51,459 psi | 83% | 2828 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,111 psi | 50% | 2444 fps | 97% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 47,892 psi | 77% | 2805 fps | 100% |
| Hodgdon Superformance | 66.8 gr | 86% | 43,468 psi | 70% | 2776 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,948 psi | 43% | 1601 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 49,182 psi | 79% | 2776 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 51,808 psi | 83% | 2812 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 45,368 psi | 73% | 2700 fps | 99.4% |
| IMR 4166 Enduron | <<locked>> | 80% | 47,688 psi | 76% | 2723 fps | 97.3% |
| IMR 4350 | <<locked>> | 86% | 41,510 psi | 67% | 2648 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,045 psi | 64% | 2595 fps | 95.1% |
| IMR 4831 | <<locked>> | 80% | 32,895 psi | 53% | 2493 fps | 95.8% |
| IMR 4895 | <<locked>> | 80% | 47,659 psi | 76% | 2789 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 80% | 52,982 psi | 85% | 2818 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 50,879 psi | 82% | 2795 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 49,995 psi | 80% | 2743 fps | 99.9% |
| Lovex S062 | <<locked>> | 80% | 45,469 psi | 73% | 2700 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 37,463 psi | 60% | 2543 fps | 95.9% |
| Lovex S070 | <<locked>> | 84% | 40,524 psi | 65% | 2631 fps | 95.6% |
| Lovex S071 | <<locked>> | 98% | 38,116 psi | 61% | 2615 fps | 95.8% |
| Norma 201 | <<locked>> | 80% | 49,632 psi | 80% | 2762 fps | 100% |
| Norma 202 | <<locked>> | 80% | 50,140 psi | 80% | 2762 fps | 100% |
| Norma 203B | <<locked>> | 80% | 45,847 psi | 74% | 2746 fps | 99.7% |
| Norma 204 | <<locked>> | 90% | 47,065 psi | 75% | 2795 fps | 95.2% |
| Norma MRP | <<locked>> | 94% | 42,090 psi | 67% | 2792 fps | 95.7% |
| Norma URP | <<locked>> | 80% | 34,156 psi | 55% | 2536 fps | 96.1% |
| Ramshot Big Game | <<locked>> | 80% | 45,745 psi | 73% | 2762 fps | 99.6% |
| Ramshot Hunter | <<locked>> | 84% | 37,840 psi | 61% | 2635 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,456 psi | 44% | 1640 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 44,092 psi | 71% | 2687 fps | 97% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 49,792 psi | 80% | 2871 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 40,219 psi | 64% | 2736 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 33,620 psi | 54% | 2549 fps | 95.6% |
| ReloadSwiss RS 70 | 61.2 gr | 82% | 35,505 psi | 57% | 2612 fps | 95.6% |
| Rottweil R 902 | <<locked>> | 80% | 47,282 psi | 76% | 2713 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 40,973 psi | 66% | 2644 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 96% | 51,155 psi | 82% | 2835 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 94% | 44,701 psi | 72% | 2772 fps | 95% |
| Rottweil R 907 | <<locked>> | 84% | 43,816 psi | 70% | 2674 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 37,463 psi | 60% | 2543 fps | 95.9% |
| Shooters World Match Rifle | <<locked>> | 80% | 50,879 psi | 82% | 2795 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 45,469 psi | 73% | 2700 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 40,524 psi | 65% | 2631 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 41,945 psi | 67% | 2694 fps | 99.2% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 51,517 psi | 83% | 2812 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 49,284 psi | 79% | 2785 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 50,647 psi | 81% | 2703 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 42,641 psi | 68% | 2569 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 39,247 psi | 63% | 2543 fps | 95% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 47,340 psi | 76% | 2828 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 50,328 psi | 81% | 2700 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 51,242 psi | 82% | 2802 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 41,321 psi | 66% | 2641 fps | 99.4% |
| Somchem S365 | <<locked>> | 80% | 30,705 psi | 49% | 2490 fps | 98.2% |
| Somchem S385 | <<locked>> | 92% | 42,554 psi | 68% | 2700 fps | 95.3% |
| Vihtavuori N133 | <<locked>> | 80% | 51,140 psi | 82% | 2690 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 47,311 psi | 76% | 2687 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 47,790 psi | 77% | 2700 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 39,581 psi | 63% | 2579 fps | 99.8% |
| Vihtavuori N160 | <<locked>> | 80% | 35,520 psi | 57% | 2539 fps | 96.5% |
| Vihtavuori N165 | <<locked>> | 98% | 44,614 psi | 72% | 2730 fps | 95.5% |
| Vihtavuori N540 | <<locked>> | 80% | 46,035 psi | 74% | 2690 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 34,983 psi | 56% | 2536 fps | 96.1% |
| Vihtavuori N555 | <<locked>> | 84% | 30,327 psi | 49% | 2480 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 34,838 psi | 56% | 2510 fps | 98.5% |
| Winchester 760 | <<locked>> | 84% | 41,481 psi | 67% | 2707 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 88% | 27,992 psi | 45% | 2487 fps | 95.9% |
| Winchester StaBALL Match | <<locked>> | 80% | 49,095 psi | 79% | 2792 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 48,182 psi | 77% | 2799 fps | 95.6% |
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 97 powders for .300 H&H Mag. loaded with the .308 | 168gr | Sellier & Bellot HPBT. Alliant Reloder-26 delivers the highest muzzle velocity at 3,031 fps; across all powders the maximum-charge window runs from 1,791 fps to 3,031 fps. Accurate 3100 gives the best case fill at 100 %, and 97 of the 97 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 168.0 gr projectile in 0.308" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Power Pro Varmint 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. ReloadSwiss RS 70, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .300 H&H Mag. with the .308 | 168gr | Sellier & Bellot HPBT 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.