Load Specifications
Load data in caliber .300 H&H Mag. with .307 | 165gr | Rhino Solid Shank bullet and 95 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.
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 2495 | <<locked>> | 84% | 55,259 psi | 89% | 2831 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 53,156 psi | 85% | 2835 fps | 97.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 49,922 psi | 80% | 2864 fps | 98.5% |
| Accurate 4064 | <<locked>> | 86% | 55,492 psi | 89% | 2884 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 55,999 psi | 90% | 2986 fps | 99.9% |
| Accurate High Countryᴾ | <<locked>> | 100% | 54,447 psi | 87% | 3061 fps | 96.2% |
| ADI AR 2206H | <<locked>> | 82% | 54,592 psi | 88% | 2907 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 55,796 psi | 89% | 2913 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 53,563 psi | 86% | 2963 fps | 96.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 54,795 psi | 88% | 3035 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 53,301 psi | 85% | 2956 fps | 96.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 56,362 psi | 90% | 2936 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 53,330 psi | 86% | 2907 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 53,127 psi | 85% | 2986 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 90% | 54,375 psi | 87% | 3015 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 56,217 psi | 90% | 3005 fps | 97.5% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 49,763 psi | 80% | 2940 fps | 96.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 46,775 psi | 75% | 2887 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 41,017 psi | 66% | 2789 fps | 97.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 53,664 psi | 86% | 3081 fps | 99.9% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 54,462 psi | 87% | 2923 fps | 99.9% |
| Bofors RP3 | <<locked>> | 86% | 53,722 psi | 86% | 2904 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 49,763 psi | 80% | 2940 fps | 96.3% |
| Bofors RP7 | <<locked>> | 90% | 53,374 psi | 86% | 2877 fps | 97.8% |
| Hodgdon H380 | <<locked>> | 86% | 54,317 psi | 87% | 2917 fps | 99.7% |
| Hodgdon H414 | <<locked>> | 92% | 54,708 psi | 88% | 2979 fps | 98.6% |
| Hodgdon H4350 | <<locked>> | 90% | 54,636 psi | 88% | 2936 fps | 97.5% |
| Hodgdon H4895 | <<locked>> | 82% | 55,172 psi | 88% | 2917 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 53,417 psi | 86% | 2910 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 55,405 psi | 89% | 2956 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 54,752 psi | 88% | 3012 fps | 98.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,085 psi | 58% | 1818 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 56,405 psi | 90% | 2920 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 55,941 psi | 90% | 2900 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 55,274 psi | 89% | 2897 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 54,723 psi | 88% | 2877 fps | 98.5% |
| IMR 4350 | <<locked>> | 94% | 54,041 psi | 87% | 2910 fps | 98% |
| IMR 4451 Enduron | <<locked>> | 90% | 54,984 psi | 88% | 2907 fps | 98.5% |
| IMR 4831 | <<locked>> | 96% | 56,391 psi | 90% | 2972 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 54,708 psi | 88% | 2936 fps | 100% |
| Lovex D073.6 | <<locked>> | 82% | 54,839 psi | 88% | 2884 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 53,606 psi | 86% | 2831 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 55,317 psi | 89% | 2890 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 54,926 psi | 88% | 2904 fps | 99.4% |
| Lovex S070 | <<locked>> | 94% | 56,028 psi | 90% | 2940 fps | 98.8% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,452 psi | 66% | 2707 fps | 96.7% |
| Norma 201 | <<locked>> | 82% | 53,534 psi | 86% | 2854 fps | 100% |
| Norma 202 | <<locked>> | 82% | 54,128 psi | 87% | 2854 fps | 100% |
| Norma 203B | <<locked>> | 86% | 55,970 psi | 90% | 2943 fps | 100% |
| Norma 204 | <<locked>> | 94% | 54,781 psi | 88% | 2959 fps | 97% |
| Norma MRPᴾ | <<locked>> | 100% | 52,692 psi | 84% | 3028 fps | 98.3% |
| Norma URP | <<locked>> | 94% | 54,549 psi | 87% | 2966 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 84% | 53,055 psi | 85% | 2913 fps | 100% |
| Ramshot Hunter | <<locked>> | 94% | 53,490 psi | 86% | 2963 fps | 99% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,767 psi | 59% | 1860 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 54,244 psi | 87% | 2897 fps | 98.9% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 54,041 psi | 87% | 2972 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 53,954 psi | 87% | 3009 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 55,724 psi | 89% | 3005 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 54,491 psi | 87% | 3031 fps | 99.8% |
| Rottweil R 902 | <<locked>> | 84% | 54,056 psi | 87% | 2854 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 53,795 psi | 86% | 2897 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 55,361 psi | 89% | 2933 fps | 96% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 55,201 psi | 89% | 2989 fps | 97.5% |
| Rottweil R 907 | <<locked>> | 90% | 53,374 psi | 86% | 2877 fps | 97.8% |
| Shooters World Long Rifle | <<locked>> | 92% | 54,926 psi | 88% | 2904 fps | 99.4% |
| Shooters World Match Rifle | <<locked>> | 82% | 54,839 psi | 88% | 2884 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 55,317 psi | 89% | 2890 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 56,028 psi | 90% | 2940 fps | 98.8% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 55,230 psi | 89% | 2953 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 55,782 psi | 89% | 2910 fps | 99.7% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 53,229 psi | 85% | 2881 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 54,317 psi | 87% | 2785 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 55,129 psi | 88% | 2789 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 54,868 psi | 88% | 2854 fps | 98.5% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 54,737 psi | 88% | 2982 fps | 97.4% |
| Somchem S335 | <<locked>> | 82% | 54,186 psi | 87% | 2785 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 55,477 psi | 89% | 2897 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 53,867 psi | 86% | 2894 fps | 100% |
| Somchem S365 | <<locked>> | 96% | 53,432 psi | 86% | 2966 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 56,130 psi | 90% | 2969 fps | 98.3% |
| Vihtavuori N133 | <<locked>> | 82% | 54,752 psi | 88% | 2769 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 54,259 psi | 87% | 2818 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 54,578 psi | 88% | 2831 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 55,158 psi | 88% | 2871 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 53,258 psi | 85% | 2907 fps | 99.7% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 48,385 psi | 78% | 2825 fps | 96.4% |
| Vihtavuori N540 | <<locked>> | 86% | 56,420 psi | 90% | 2877 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 55,898 psi | 90% | 2966 fps | 99.8% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 52,446 psi | 84% | 2969 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 53,084 psi | 85% | 2881 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 54,708 psi | 88% | 2979 fps | 98.6% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 42,177 psi | 68% | 2927 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 53,243 psi | 85% | 2887 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 52,547 psi | 84% | 2900 fps | 96.6% |
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% | 48,530 psi | 78% | 2736 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 46,586 psi | 75% | 2720 fps | 96.2% |
| Accurate 3100 | <<locked>> | 92% | 37,869 psi | 61% | 2631 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 45,948 psi | 74% | 2736 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,461 psi | 55% | 2569 fps | 96.3% |
| Accurate High Country | <<locked>> | 98% | 50,734 psi | 81% | 2995 fps | 95.3% |
| ADI AR 2206H | <<locked>> | 80% | 51,329 psi | 82% | 2854 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 43,569 psi | 70% | 2700 fps | 99% |
| ADI AR 2209 | <<locked>> | 94% | 46,934 psi | 75% | 2838 fps | 95.2% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 47,747 psi | 77% | 2910 fps | 99.6% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 46,963 psi | 75% | 2841 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 43,932 psi | 70% | 2730 fps | 99.8% |
| Alliant Reloder-15 | <<locked>> | 80% | 46,876 psi | 75% | 2795 fps | 99.5% |
| Alliant Reloder-16 | <<locked>> | 80% | 34,055 psi | 55% | 2582 fps | 96.3% |
| Alliant Reloder-17 | 60.3 gr | 80% | 38,305 psi | 61% | 2713 fps | 99.1% |
| Alliant Reloder-19 | <<locked>> | 94% | 46,369 psi | 74% | 2831 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 98% | 46,470 psi | 75% | 2877 fps | 95.4% |
| Alliant Reloder-23 | <<locked>> | 84% | 28,224 psi | 45% | 2438 fps | 95.3% |
| Alliant Reloder-25 | <<locked>> | 96% | 36,085 psi | 58% | 2667 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 88% | 34,664 psi | 56% | 2677 fps | 95.8% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 51,039 psi | 82% | 2867 fps | 99.7% |
| Bofors RP3 | <<locked>> | 80% | 43,918 psi | 70% | 2736 fps | 99.9% |
| Bofors RP5 | <<locked>> | 98% | 46,470 psi | 75% | 2877 fps | 95.4% |
| Bofors RP7 | <<locked>> | 82% | 41,611 psi | 67% | 2657 fps | 95% |
| Hodgdon H380 | <<locked>> | 80% | 44,556 psi | 71% | 2743 fps | 98.5% |
| Hodgdon H414 | <<locked>> | 84% | 41,930 psi | 67% | 2740 fps | 95.8% |
| Hodgdon H4350 | <<locked>> | 84% | 45,020 psi | 72% | 2759 fps | 95.2% |
| Hodgdon H4895 | <<locked>> | 80% | 51,851 psi | 83% | 2864 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,502 psi | 51% | 2480 fps | 97.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 48,428 psi | 78% | 2844 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 44,048 psi | 71% | 2815 fps | 96% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,006 psi | 43% | 1624 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 49,603 psi | 80% | 2815 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 52,388 psi | 84% | 2851 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 45,818 psi | 73% | 2736 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,269 psi | 77% | 2762 fps | 97.4% |
| IMR 4350 | <<locked>> | 86% | 42,105 psi | 68% | 2687 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,364 psi | 65% | 2631 fps | 95.1% |
| IMR 4831 | <<locked>> | 80% | 33,272 psi | 53% | 2526 fps | 95.9% |
| IMR 4895 | <<locked>> | 80% | 48,066 psi | 77% | 2825 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 51,474 psi | 83% | 2831 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 50,473 psi | 81% | 2782 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 45,919 psi | 74% | 2736 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 38,014 psi | 61% | 2582 fps | 96% |
| Lovex S070 | <<locked>> | 84% | 40,988 psi | 66% | 2667 fps | 95.7% |
| Lovex S071 | <<locked>> | 96% | 36,448 psi | 58% | 2598 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 50,343 psi | 81% | 2802 fps | 100% |
| Norma 202 | <<locked>> | 80% | 50,836 psi | 82% | 2802 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,238 psi | 74% | 2782 fps | 99.7% |
| Norma 204 | <<locked>> | 90% | 47,747 psi | 77% | 2835 fps | 95.3% |
| Norma MRP | <<locked>> | 94% | 42,815 psi | 69% | 2838 fps | 95.9% |
| Norma URP | <<locked>> | 80% | 34,563 psi | 55% | 2569 fps | 96.1% |
| Ramshot Big Game | <<locked>> | 80% | 46,456 psi | 74% | 2802 fps | 99.7% |
| Ramshot Hunter | <<locked>> | 84% | 38,377 psi | 62% | 2671 fps | 95.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,499 psi | 44% | 1667 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 44,585 psi | 71% | 2723 fps | 97.1% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 50,430 psi | 81% | 2913 fps | 99.8% |
| ReloadSwiss RS 60 | 60.3 gr | 80% | 40,741 psi | 65% | 2776 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,272 psi | 55% | 2589 fps | 95.8% |
| ReloadSwiss RS 70 | 62.8 gr | 82% | 35,998 psi | 58% | 2648 fps | 95.8% |
| Rottweil R 902 | <<locked>> | 80% | 47,776 psi | 77% | 2753 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 41,423 psi | 66% | 2680 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 96% | 51,764 psi | 83% | 2874 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 94% | 45,353 psi | 73% | 2815 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 82% | 41,611 psi | 67% | 2657 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,014 psi | 61% | 2582 fps | 96% |
| Shooters World Match Rifle | <<locked>> | 80% | 51,474 psi | 83% | 2831 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 45,919 psi | 74% | 2736 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 40,988 psi | 66% | 2667 fps | 95.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,453 psi | 68% | 2733 fps | 99.2% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 52,199 psi | 84% | 2854 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 49,835 psi | 80% | 2825 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 51,213 psi | 82% | 2740 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 43,105 psi | 69% | 2605 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 39,697 psi | 64% | 2579 fps | 95.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 44,933 psi | 72% | 2808 fps | 95% |
| Somchem S335 | <<locked>> | 80% | 50,995 psi | 82% | 2740 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 51,938 psi | 83% | 2844 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 41,974 psi | 67% | 2684 fps | 99.5% |
| Somchem S365 | <<locked>> | 80% | 31,053 psi | 50% | 2523 fps | 98.3% |
| Somchem S385 | <<locked>> | 92% | 43,192 psi | 69% | 2740 fps | 95.5% |
| Vihtavuori N133 | <<locked>> | 80% | 51,692 psi | 83% | 2726 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 47,906 psi | 77% | 2723 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,211 psi | 77% | 2736 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 39,958 psi | 64% | 2615 fps | 99.8% |
| Vihtavuori N160 | <<locked>> | 80% | 35,911 psi | 58% | 2572 fps | 96.6% |
| Vihtavuori N165 | <<locked>> | 98% | 45,121 psi | 72% | 2766 fps | 95.6% |
| Vihtavuori N540 | <<locked>> | 80% | 46,601 psi | 75% | 2726 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,491 psi | 57% | 2572 fps | 96.2% |
| Vihtavuori N555 | <<locked>> | 84% | 30,821 psi | 49% | 2516 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,288 psi | 57% | 2546 fps | 98.5% |
| Winchester 760 | <<locked>> | 84% | 41,930 psi | 67% | 2740 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 88% | 28,326 psi | 45% | 2523 fps | 96% |
| Winchester StaBALL Match | <<locked>> | 80% | 49,632 psi | 80% | 2828 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 49,095 psi | 79% | 2844 fps | 95.8% |
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 95 powders for .300 H&H Mag. loaded with the .307 | 165gr | Rhino Solid Shank. Alliant Reloder-26 delivers the highest muzzle velocity at 3,081 fps; across all powders the maximum-charge window runs from 1,818 fps to 3,081 fps. Accurate 3100 gives the best case fill at 100 %, and 95 of the 95 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 165.0 gr projectile in 0.307" calls for a 1:15.0 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 .307 | 165gr | Rhino Solid Shank 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.