Load Specifications
Load data in caliber .300 H&H Mag. with .308 | 175gr | Prvi Partizan FMJ BT bullet and 96 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Alliant Reloder-17 and ReloadSwiss RS 60.
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% | 55,100 psi | 88% | 2736 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 52,997 psi | 85% | 2743 fps | 97.8% |
| Accurate 3100ᴾ | <<locked>> | 100% | 49,647 psi | 80% | 2776 fps | 98.7% |
| Accurate 4064 | <<locked>> | 86% | 55,230 psi | 89% | 2789 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 55,724 psi | 89% | 2887 fps | 100% |
| Accurate High Countryᴾ | <<locked>> | 100% | 53,998 psi | 87% | 2963 fps | 96.5% |
| ADI AR 2206H | <<locked>> | 82% | 54,462 psi | 87% | 2812 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 55,709 psi | 89% | 2818 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 53,142 psi | 85% | 2864 fps | 97.1% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 54,694 psi | 88% | 2940 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 53,171 psi | 85% | 2864 fps | 97.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 56,304 psi | 90% | 2841 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 53,084 psi | 85% | 2812 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 96% | 56,289 psi | 90% | 2940 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 53,867 psi | 86% | 2917 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 55,941 psi | 90% | 2913 fps | 97.8% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 49,342 psi | 79% | 2848 fps | 96.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 46,615 psi | 75% | 2795 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 40,785 psi | 65% | 2703 fps | 97.6% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 53,127 psi | 85% | 2982 fps | 99.9% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 54,346 psi | 87% | 2831 fps | 100% |
| Bofors RP3 | <<locked>> | 86% | 53,432 psi | 86% | 2805 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 49,342 psi | 79% | 2848 fps | 96.6% |
| Bofors RP7 | <<locked>> | 90% | 53,214 psi | 85% | 2785 fps | 98.1% |
| Hodgdon H380 | <<locked>> | 86% | 54,143 psi | 87% | 2822 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 92% | 54,273 psi | 87% | 2881 fps | 98.8% |
| Hodgdon H4350 | <<locked>> | 90% | 54,476 psi | 87% | 2841 fps | 97.7% |
| Hodgdon H4895 | <<locked>> | 82% | 55,042 psi | 88% | 2822 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 53,084 psi | 85% | 2815 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 55,216 psi | 89% | 2858 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 54,375 psi | 87% | 2917 fps | 98.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,216 psi | 58% | 1749 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 56,130 psi | 90% | 2825 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 55,550 psi | 89% | 2799 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 54,998 psi | 88% | 2799 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 54,578 psi | 88% | 2782 fps | 98.7% |
| IMR 4350 | <<locked>> | 94% | 53,809 psi | 86% | 2815 fps | 98.2% |
| IMR 4451 Enduron | <<locked>> | 90% | 54,882 psi | 88% | 2815 fps | 98.7% |
| IMR 4831 | <<locked>> | 96% | 56,043 psi | 90% | 2877 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 54,476 psi | 87% | 2838 fps | 100% |
| IMR 4955 Enduronᴾ | <<locked>> | 100% | 56,347 psi | 90% | 2851 fps | 96% |
| Lovex D073.6 | <<locked>> | 82% | 54,621 psi | 88% | 2785 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 53,563 psi | 86% | 2740 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 55,303 psi | 89% | 2795 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 54,694 psi | 88% | 2808 fps | 99.5% |
| Lovex S070 | <<locked>> | 94% | 55,999 psi | 90% | 2851 fps | 99% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,075 psi | 66% | 2621 fps | 97% |
| Norma 201 | <<locked>> | 82% | 53,287 psi | 85% | 2756 fps | 100% |
| Norma 202 | <<locked>> | 82% | 53,882 psi | 86% | 2756 fps | 100% |
| Norma 203B | <<locked>> | 86% | 55,869 psi | 90% | 2851 fps | 100% |
| Norma 204 | <<locked>> | 94% | 54,317 psi | 87% | 2861 fps | 97.2% |
| Norma MRPᴾ | <<locked>> | 100% | 52,199 psi | 84% | 2933 fps | 98.5% |
| Norma URP | <<locked>> | 94% | 54,491 psi | 87% | 2871 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 84% | 53,026 psi | 85% | 2822 fps | 100% |
| Ramshot Hunter | <<locked>> | 94% | 52,997 psi | 85% | 2867 fps | 99.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,738 psi | 59% | 1788 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 53,911 psi | 86% | 2802 fps | 99% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 53,867 psi | 86% | 2877 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 53,577 psi | 86% | 2910 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 55,274 psi | 89% | 2907 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 53,969 psi | 87% | 2933 fps | 99.8% |
| Rottweil R 902 | <<locked>> | 84% | 53,867 psi | 86% | 2759 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 53,563 psi | 86% | 2802 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 54,868 psi | 88% | 2838 fps | 96.3% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 54,853 psi | 88% | 2894 fps | 97.7% |
| Rottweil R 907 | <<locked>> | 90% | 53,214 psi | 85% | 2785 fps | 98.1% |
| Shooters World Long Rifle | <<locked>> | 92% | 54,694 psi | 88% | 2808 fps | 99.5% |
| Shooters World Match Rifle | <<locked>> | 82% | 54,621 psi | 88% | 2785 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 55,303 psi | 89% | 2795 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 55,999 psi | 90% | 2851 fps | 99% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 55,027 psi | 88% | 2858 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 55,622 psi | 89% | 2815 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 53,069 psi | 85% | 2785 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 54,346 psi | 87% | 2694 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 55,071 psi | 88% | 2697 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 54,520 psi | 87% | 2762 fps | 98.7% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 54,404 psi | 87% | 2887 fps | 97.6% |
| Somchem S335 | <<locked>> | 82% | 53,911 psi | 86% | 2690 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 55,303 psi | 89% | 2805 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 53,563 psi | 86% | 2799 fps | 100% |
| Somchem S365 | <<locked>> | 96% | 53,272 psi | 85% | 2874 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 55,724 psi | 89% | 2874 fps | 98.5% |
| Vihtavuori N133 | <<locked>> | 82% | 54,795 psi | 88% | 2677 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 54,186 psi | 87% | 2723 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 54,520 psi | 87% | 2736 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 54,781 psi | 88% | 2772 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 53,127 psi | 85% | 2815 fps | 99.8% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 48,109 psi | 77% | 2736 fps | 96.7% |
| Vihtavuori N540 | <<locked>> | 86% | 56,217 psi | 90% | 2782 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 55,825 psi | 90% | 2874 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 51,982 psi | 83% | 2871 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 56,333 psi | 90% | 2838 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 54,534 psi | 87% | 2884 fps | 98.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 41,930 psi | 67% | 2838 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 52,982 psi | 85% | 2792 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 52,214 psi | 84% | 2808 fps | 96.9% |
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% | 48,385 psi | 78% | 2641 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 46,383 psi | 74% | 2631 fps | 96.5% |
| Accurate 3100 | <<locked>> | 90% | 35,215 psi | 56% | 2497 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 45,788 psi | 73% | 2644 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,447 psi | 55% | 2493 fps | 96.7% |
| Accurate High Country | <<locked>> | 98% | 50,372 psi | 81% | 2900 fps | 95.6% |
| ADI AR 2206H | <<locked>> | 80% | 51,300 psi | 82% | 2762 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 43,598 psi | 70% | 2615 fps | 99.3% |
| ADI AR 2209 | <<locked>> | 94% | 46,717 psi | 75% | 2749 fps | 95.5% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 47,398 psi | 76% | 2815 fps | 99.7% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 46,804 psi | 75% | 2753 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 43,801 psi | 70% | 2641 fps | 99.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 46,833 psi | 75% | 2703 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 80% | 33,910 psi | 54% | 2500 fps | 96.7% |
| Alliant Reloder-17 | 57.4 gr | 80% | 38,087 psi | 61% | 2625 fps | 99.3% |
| Alliant Reloder-19 | <<locked>> | 94% | 46,209 psi | 74% | 2746 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 98% | 46,151 psi | 74% | 2792 fps | 95.8% |
| Alliant Reloder-23 | <<locked>> | 84% | 28,137 psi | 45% | 2365 fps | 95.8% |
| Alliant Reloder-25 | <<locked>> | 96% | 36,013 psi | 58% | 2589 fps | 95.9% |
| Alliant Reloder-26 | <<locked>> | 86% | 32,184 psi | 52% | 2536 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 50,749 psi | 81% | 2772 fps | 99.8% |
| Bofors RP3 | <<locked>> | 80% | 43,932 psi | 70% | 2651 fps | 99.9% |
| Bofors RP5 | <<locked>> | 98% | 46,151 psi | 74% | 2792 fps | 95.8% |
| Bofors RP7 | <<locked>> | 82% | 41,437 psi | 66% | 2569 fps | 95.3% |
| Hodgdon H380 | <<locked>> | 80% | 44,425 psi | 71% | 2654 fps | 98.7% |
| Hodgdon H414 | <<locked>> | 82% | 38,957 psi | 62% | 2595 fps | 95.3% |
| Hodgdon H4350 | <<locked>> | 84% | 44,889 psi | 72% | 2674 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 51,837 psi | 83% | 2772 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,488 psi | 50% | 2402 fps | 97.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 48,167 psi | 77% | 2753 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 40,944 psi | 66% | 2667 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,079 psi | 43% | 1562 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 49,530 psi | 79% | 2723 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 52,112 psi | 84% | 2753 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 45,832 psi | 73% | 2648 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,051 psi | 77% | 2674 fps | 97.6% |
| IMR 4350 | <<locked>> | 86% | 42,018 psi | 67% | 2602 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,292 psi | 65% | 2546 fps | 95.5% |
| IMR 4831 | <<locked>> | 80% | 33,214 psi | 53% | 2448 fps | 96.3% |
| IMR 4895 | <<locked>> | 80% | 48,037 psi | 77% | 2733 fps | 99.9% |
| IMR 4955 Enduron | <<locked>> | 98% | 52,866 psi | 85% | 2795 fps | 95.2% |
| Lovex D073.6 | <<locked>> | 80% | 51,140 psi | 82% | 2736 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 50,502 psi | 81% | 2690 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 45,948 psi | 74% | 2648 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 37,884 psi | 61% | 2500 fps | 96.4% |
| Lovex S070 | <<locked>> | 82% | 38,363 psi | 62% | 2530 fps | 95.3% |
| Lovex S071 | <<locked>> | 96% | 36,100 psi | 58% | 2516 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 50,154 psi | 80% | 2710 fps | 100% |
| Norma 202 | <<locked>> | 80% | 50,705 psi | 81% | 2710 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,209 psi | 74% | 2694 fps | 99.8% |
| Norma 204 | <<locked>> | 90% | 47,456 psi | 76% | 2746 fps | 95.7% |
| Norma MRP | <<locked>> | 92% | 39,726 psi | 64% | 2687 fps | 95.3% |
| Norma URP | <<locked>> | 80% | 34,461 psi | 55% | 2490 fps | 96.6% |
| Ramshot Big Game | <<locked>> | 80% | 46,064 psi | 74% | 2710 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 82% | 35,737 psi | 57% | 2530 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,427 psi | 44% | 1598 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 44,527 psi | 71% | 2638 fps | 97.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 50,314 psi | 81% | 2818 fps | 99.9% |
| ReloadSwiss RS 60 | 57.4 gr | 80% | 40,509 psi | 65% | 2684 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,055 psi | 55% | 2507 fps | 96.2% |
| ReloadSwiss RS 70 | 58.3 gr | 80% | 33,417 psi | 54% | 2507 fps | 95.1% |
| Rottweil R 902 | <<locked>> | 80% | 47,732 psi | 77% | 2661 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 41,336 psi | 66% | 2595 fps | 99.7% |
| Rottweil R 904 | <<locked>> | 96% | 51,590 psi | 83% | 2785 fps | 95.6% |
| Rottweil R 905 | <<locked>> | 94% | 45,107 psi | 72% | 2726 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 82% | 41,437 psi | 66% | 2569 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 80% | 37,884 psi | 61% | 2500 fps | 96.4% |
| Shooters World Match Rifle | <<locked>> | 80% | 51,140 psi | 82% | 2736 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 45,948 psi | 74% | 2648 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 38,363 psi | 62% | 2530 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,409 psi | 68% | 2648 fps | 99.4% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 52,141 psi | 84% | 2762 fps | 99.6% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 49,777 psi | 80% | 2733 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 51,097 psi | 82% | 2648 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 42,989 psi | 69% | 2516 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 39,624 psi | 64% | 2497 fps | 95.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 44,686 psi | 72% | 2720 fps | 95.4% |
| Somchem S335 | <<locked>> | 80% | 50,821 psi | 81% | 2648 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 51,619 psi | 83% | 2749 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 41,800 psi | 67% | 2595 fps | 99.6% |
| Somchem S365 | <<locked>> | 80% | 30,980 psi | 50% | 2448 fps | 98.6% |
| Somchem S385 | <<locked>> | 92% | 42,931 psi | 69% | 2654 fps | 95.8% |
| Vihtavuori N133 | <<locked>> | 80% | 51,576 psi | 83% | 2635 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 47,776 psi | 77% | 2631 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,095 psi | 77% | 2644 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 39,885 psi | 64% | 2530 fps | 99.9% |
| Vihtavuori N160 | <<locked>> | 80% | 35,853 psi | 57% | 2493 fps | 97% |
| Vihtavuori N165 | <<locked>> | 96% | 42,047 psi | 67% | 2625 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 46,456 psi | 74% | 2638 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,375 psi | 57% | 2493 fps | 96.6% |
| Vihtavuori N555 | <<locked>> | 84% | 30,705 psi | 49% | 2441 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,099 psi | 56% | 2464 fps | 98.8% |
| Winchester 760 | <<locked>> | 82% | 39,175 psi | 63% | 2598 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 86% | 26,455 psi | 42% | 2385 fps | 95.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 49,429 psi | 79% | 2736 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 45,426 psi | 73% | 2694 fps | 95.2% |
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 96 powders for .300 H&H Mag. loaded with the .308 | 175gr | Prvi Partizan FMJ BT. Alliant Reloder-26 delivers the highest muzzle velocity at 2,982 fps; across all powders the maximum-charge window runs from 1,749 fps to 2,982 fps. Accurate 3100 gives the best case fill at 100 %, and 96 of the 96 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 175.0 gr projectile in 0.308" calls for a 1:12.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate High Country, Alliant Reloder-19 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, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .300 H&H Mag. with the .308 | 175gr | Prvi Partizan FMJ BT 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.